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Jekyll2017-04-24T08:23:50-04:00https://civilityandtruth.com/Civility and TruthHoward County, Maryland, and points beyondFrank firstname.lastname@example.com the Chrysalis: Details, details2017-04-21T07:40:00-04:002017-04-21T07:40:00-04:00https://civilityandtruth.com/2017/04/21/creating-the-chrysalis-details-details

Wooden pickets at the rear of the Chrysalis, forming guard rails for the stage. (Click for a higher-resolution version.) The perforated aluminum sheets in the background cover and protect the ZEPPS panels closest to the stage floor. Image © 2017 Living Design Lab; used with permission.

tl;dr: Getting the details right on the Chrysalis, featuring Living Design Lab and Mahan Rykiel Associates.

This article is one in a series exploring in depth the creation of the Chrysalis amphitheater in Merriweather Park at Symphony Woods in Columbia, Maryland. For the complete list of articles please see the introduction to the series.

Previous articles in this series discussed the design, fabrication and installation of the steel frame and skin of the Chrysalis, as well as the construction of the "subfloor" to which the steel frame is attached. This article completes that discussion, focusing on various details of the Chrysalis design and construction not previously covered. It features the work of Living Design Lab, architect for the Chrysalis, and Mahan Rykiel Associates, the landscape architect.

The wooden boardwalk and ramp leading to the Chrysalis stage. (Click for a higher-resolution version.) The boardwalk abuts the clay pavers in front of the stage where the traffic cones are placed. Image © 2017 Inner Arbor Trust; used with permission.

Living Design Lab

The "Chrysalis Team" page on the merriweatherpark.org web site includes a number of people and companies previously discussed in this series, including Marc Fornes and THEVERYMANY, Arup, Zahner, and Whiting-Turner. Right near the top of the list you'll find listed Living Design Lab as architect.

To quote Wikipedia, an architect "plans, designs, and reviews the construction of buildings". Whether or not there's a separate designer on the project (as there was for the Chrysalis), ultimately the architect is responsible for the project being able to meet the needs of the people who are going to use it.

As noted above, for the Chrysalis the Inner Arbor Trust chose as architect Living Design Lab, a Baltimore firm founded in 2014 by Davin Hong, subsequently joined by Kevin Day. The principals of Living Design Lab have shown a willingness to stretch themselves, to take on complex and ambitious projects with multiple stakeholders, to practice design above the level of a isolated building or structure, and to do work that serves the community as a whole and not just their client.

Projects on which they've worked include advocacy for an integrated design approach to renewing Baltimore's schools and their surrounding neighborhoods, a project to revitalize Greenmount Avenue in Baltimore, the Baltimore Green Network—an ambitious plan to create an interconnected system of greenspaces throught the city—and a project to build cities for refugees in the Middle East in place of their current camps.

This background prepared Living Design Lab to play a key role in the complex and ambitious project that was the Chrysalis, working with THEVERYMANY, Arup, and Zahner to take the formal concept of the Chrysalis—the 3-dimensional form created through the parametric design process—and make a buildable structure able to handle the demands to be placed upon it.

A rendering showing the wooden pickets, the brackets by which they are attached, and the aluminum support plate to which the brackets are attached. (Click for a higher-resolution version.) Image © 2014 Inner Arbor Trust; used with permission.

Sweating the details

Even a typical architectural project involves a myriad of details, more or less visible to the people using it. Less visible details include those needed to satisfy local authorities that a building or other structure will be safe for people and satisfy other requirements: Does it provide adequate fire protection? Does it comply with ADA requirements regarding access? What about handling of storm water runoff? And so on…

Even the more visible details often go unnoticed by many, but can elicit a sense of delight when done really well, or irritation when done poorly—think of how satisfied we feel when we hold and use a really well-designed smartphone, for example, or how we're annoyed when we pay thousands for a new car only to find that the body panels aren't consistently joined, or that an otherwise sumptuous interior is spoiled by misplaced controls and cheap plastic parts. And of course we want good design for an reasonable price.

For the Chrysalis Living Design Lab dealt with both types of details, working to understand and satisfy a myriad of technical requirements related to the function, construction, cost, schedule, and regulatory approval of the Chrysalis, all without compromising the design intent. For example, consider the question of fire protection: Above the stage floor the Chrysalis is a pure metal structure of steel and aluminum. Arguably a conventional building sprinkler system is neither necessary nor appropriate for the Chrysalis—just one of the many issues that had to be negotiated with Howard County officials for a structure very different than those that typically come before them.

Previous articles have discussed various strategies employed to preserve the design intent for the Chrysalis—so often compromised in projects—while making it possible for it to fulfill its purposes, including most notably serving as a professional performance stage. These strategies included the introduction of the steel framework with its "spine" of primary steel and "ribs" of secondary steel to support heavy theatrical loads and resist dynamic wind loads, and the use of ZEPPS panels to support the pleated surface of aluminum shingles.

This attention to design intent and the uniqueness of the Chrysalis extended to other aspects as well. To explore just one, consider the wooden pickets attached to the exterior of the Chrysalis subfloor (see the first figure above). These pickets are Living Design Lab's elegant solution to three separate problems:

First, code requirements dictate that there be adequate protection to prevent people from falling off the stage and other surfaces greater than a certain height above the ground. Second, aesthetic considerations dictate that some sort of screening be provided for the otherwise uninterrupted expanses of concrete forming the exterior walls of the subfloor. Finally, budget considerations mean that any solution must not be overly expensive to fabricate and install.

The solution that Living Design Lab came up with was to use vertical wooden pickets (of the same ipe hardwood used for the stage floor) extending from the ground either to the stage floor (at the front of the stage) or beyond it (at the rear of the stage) to form guard rails. The result is more aesthetically pleasing than using conventional railings for the stage and a separate screen or facade for the exterior walls.

But how to build and install these wooden pickets, given that they have to both follow the curve of the stage floor and also match up with the angled legs of the Chrysalis at the points where the guard rails meet the legs? Every picket might have a different orientation in 3-dimensional space, and thus have to be attached in a slightly different way.

For the solution to the problem see the rendering above: Each picket is attached to a angled aluminum attachment bracket. Different attachment brackets have different angles, so that their respective pickets can assume different angles to the ground depending on the degree to which the underlying subfloor wall "leans in". (Viewing the picket from above and comparing it to an airplane, this is the "pitch" angle.)

Each picket is free to rotate around the bolt attaching it to its bracket, so it can also be slanted to the left or right in a direction parallel to the exterior subfloor wall—in airplane terms, the "roll" angle of the picket can change. Finally, the bracket itself is attached to a horizontal aluminum support plate in such a way that the bracket and its attached picket can "yaw" back and forth slightly to match the curve of the stage floor and the positions of its neighboring pickets.

This arrangement of pickets, brackets, and support plates, elegant as it is, would be too expensive to fabricate if each bracket had to be unique, and too complicated to install as well, given the need to adjust the pickets to precise angles. To address this, the system was designed to require only a limited number of types of brackets, each holding a picket to a particular angle to the ground. The underside of each support plate was then marked to indicate to the installers the type of bracket to be used at each position, together with a line to indicate how the installer should align each bracket relative to the plate (the "yaw" angle).

This system is but one example where having a balance of technical expertise with design sophistication enabled Living Design Lab and the other members of the core Chrysalis team to realize the form of the Chrysalis as a buildable design within a reasonable budget and time schedule.

Pervious clay pavers forming the pedestrian area in front of the Chrysalis stage. (Click for a higher-resolution version.) To the upper right is the walkable access road leading to the Chrysalis from the Merriweather Post Pavilion VIP parking lot. In the background is the beta stage. (See also the figure below.) Image © 2017 Inner Arbor Trust; used with permission.

Mahan Rykiel Associates

While Living Design Lab is a relatively new firm, Mahan Rykiel Associates has been a fixture of the Baltimore scene for over 30 years. Founded by Catherine Mahan in 1983 as Catherine Mahan Associates, it became Mahan Rykiel Associates after Scott Rykiel joined the firm in 1993 and became a partner with Mahan.

Mahan Rykiel has completed or is currently working on a host of projects in the Baltimore-Washington region, including several involving parks: Harbor Point on the waterfront west of Fells Point, Pierce's Park next to the Columbus Center at the Inner Harbor, Eager Park north of Johns Hopkins University, and Fern Valley and the National Capitol Columns at the U.S. National Arboretum.

Closer to home, Mahan Rykiel has many associations with Columbia: Scott Rykiel used to work at the Columbia-based firm LDR International, two partners at the firm currently live in Columbia, and Mahan Rykiel has been involved with downtown Columbia projects for over ten years, including being the landscape architect for the Columbia Association's Symphony Woods Park project.

After the Columbia Association decided to adopt the Inner Arbor plan and created the Inner Arbor Trust to carry it out, the Trust decided to take advantage of Mahan Rykiel's deep knowledge of Symphony Woods and added them to the design team for Merriweather Park at Symphony Woods.

The accessible path leading to the Chrysalis. (Click for a higher-resolution version.) The view is looking up the hill from the alpha stage to the Merriweather Post Pavilion VIP parking lot. Image © 2017 Inner Arbor Trust; used with permission.

Getting to and from the Chrysalis

In joining the Inner Arbor design team one major task Mahan Rykiel took on was that of creating a new path system for Symphony Woods—fulfilling the mandate of the Howard County Planning Board to minimize tree removal by "aligning paths around healthy trees and minimizing grading". Mahan Rykiel's work at the Chrysalis represents the beginning of creating a comprehensive system of meandering paths for Merriweather Park at Symphony Woods, as seen in the multiple pedestrian areas around the structure.

The first is an 8-foot-wide accessible path leading to the Chrysalis from a set of seven new handicap parking spaces at the Merriweather VIP parking lot. This path winds around the existing Merriweather Post Pavilion administrative offices and concludes in front of the Chrysalis between the alpha and beta stages.

In order to minimize the slope of the accessible path it goes below grade a bit for one section, in which it is flanked by low walls made of natural stone from the region. To minimize storm water runoff the accessible path features flexible pervious pavement made from recycled tire granules, aggregate rock, and a binding agent. (See the figure above.)

At the Chrysalis the accessible path terminates in a pedestrian area in front of the alpha and beta stages. This area uses light-colored pervious clay pavers, again to minimize storm water runoff. (See the figure above.)

At the south end of the Chrysalis concrete and wooden steps lead to the beta stage. At the north end of the Chrysalis the clay pavers transition to a wooden ramp that provides an accessible approach to the alpha stage floor. This ramp is surfaced with the same ipe hardwood used for the Chrysalis stage floor, and flanked by the same wooden picket discussed above, serving as guard rails. (See the figure above.)

At present this elevated wooden boardwalk is relatively short. However, in phase 2 of the development of Merriweather Park at Symphony Woods the boardwalk will be extended west and then northeast to provide an accessible path to the Chrysalis from a new entrance to the park at the corner of Little Patuxent Parkway and South Entrance Road, next to the multi-use pathway to Lake Kittamaqundi.

The final approach to the Chrysalis is via a short access road providing vehicular access to the loading dock at the rear of the alpha stage. Paved with asphalt and edged with cobblestones, this road provides another walkable approach to the Chrysalis.

Supplemented by landscaping work around the Chrysalis to restore a more natural landscape, the Chrysalis path system and the other areas surrounding the Chrysalis represent Merriweather Park at Symphony Woods in miniature, foreshadowing how Mahan Rykiel's work will enhance Symphony Woods during the subsequent phases of park development.

The stage floor of the Chrysalis in the process of being installed. (Click for a higher-resolution version.) The black cylinders are Bison adjustable deck supports, each holding up one corner of four adjacent wooden tiles. Image © 2017 Frank Hecker; available under the terms of the Creative Commons Attribution 4.0 International License.

Taking the stage

Another key element of the Chrysalis in its final form, important to performers and audience alike, is the stage floor.

This floor has to satisfy several requirements: it has to provide as level a surface as possible; bear the weight of performers, their equipment, and an on-stage audience that might number in the hundreds; be yielding enough for dance and related performances; be sturdy enough to last a long time while exposed to the elements; provide adequate space for electrical cabling and other below-stage equipment; allow for easy repair if damaged; and, finally, be installable above a concrete surface that may be somewhat uneven in places.

The path to a solution began with Michael McCall, the president of the Inner Arbor Trust: in the course of planning a deck for his own home, McCall came across the Bison system of wooden floor tiles and adjustable deck supports. (See the figure above.) Living Design Lab and Arup evaluated the system, and based on its multiple advantages the Chrysalis team decided to adopt it for the main stage floor.

Each Bison unit supports the corners of four adjacent wooden tiles. The deck supports are threaded to allow fine adjustments to be made to the height of the tiles to make the stage floor as level as possible. If needed the base of each unit can also be adjusted to compensate for the underlying surface sloping somewhat.

The wooden tiles for the floor are 2-foot by 2-foot and (like the wooden pickets and the ramp to the Chrysalis) are made of ipe hardwood. They are elevated several inches above the underlying concrete subfloor to allow space for electrical cabling and other equipment, and can be individually removed if needed to gain access to the space under the stage floor. They can also be individually replaced if damaged.

The Inner Arbor Trust also took advantage of the nature of the tiles to mount a fundraising campaign, allowing people or organizations to have their names or other texts laser-engraved on the individual planks of the tiles in return for donations. The final form of the Chrysalis stage floor thus reflects not only the contributions of Living Design Lab, Arup, and the other members of the Chrysalis team, but also the contributions of the many other people and organizations who have helped bring the Chrysalis to life.

The Chrysalis stage floor as installed, with engraved wooden tiles. (Click for a higher-resolution version.) Image © 2017 Howard County, Maryland.

For further exploration

This article is based on material from a variety of sources, including the following:

For more on Living Design Lab and its principals, Davin Hong and Kevin Day, see the following:

Living Design Lab. The firm's web site.

Davin Hong. Professional biography of Davin Hong.

Kevin Day. Professional biography of Kevin Day.

"Building communities through schools: An interview with Davin Hong. A 2013 interview with Davin Hong.

For more on Mahan Rykiel Associates, see the following:

Mahan Rykiel Associates/Practice. About page on the Mahan Rykiel site.

"Moving heaven & earth", by Stephanie Shapiro, page 1C, Baltimore Sun, October 9, 2006. Includes a profile of Scott Rykiel.

"Devoted to 'creating wonderful outdoor spaces'", by Lorraine Mirabella, page 3C, Baltimore Sun, April 1, 2012. An interview with Catherine Mahan on her retirement from Mahan Rykiel, discussing the history of the firm.

"Unabashed Designers of Delight" [121-minute video] (November 18, 2013). A presentation introducing the design team for the Inner Arbor plan. It includes a presentation by Scott Rykiel beginning at 41:54.

For more on the Chrysalis stage floor see the following:

Bison Innovative Products and example deck supports and floor tiles.

Entry for ipe (the hardwood used in the stage floor tiles and pickets) at the online Wood Database.

Engraving for the Chrysalis stage floor tiles.

For more on the Chrysalis amphitheater and its origins in the Inner Arbor concept plan, see the following:

Michael McCall presentation of the Inner Arbor concept plan to Leadership Howard County [33-minute video] (September 20, 2013).

The Chrysalis portion of the Inner Arbor pre-submission community presentation (December 2, 2013).

Michael McCall presentation to the Howard County Design Advisory Panel [20-minute video] (February 26, 2014).

For more of my opinions on and explanations of various aspects of the Chrysalis and Merriweather Park at Symphony Woods, see the Inner Arbor-related posts in the series "The Inner Arbor plan takes shape" and elsewhere on this blog. (Note that some of these posts contain outdated information relating to park features that were later dropped or revised.)

Frank email@example.com the details right on the Chrysalis, featuring Living Design Lab and Mahan Rykiel Associates.Creating the Chrysalis: What comes next2017-04-14T09:30:00-04:002017-04-14T09:30:00-04:00https://civilityandtruth.com/2017/04/14/creating-the-chrysalis-what-comes-next

Site plan for the northern portion of Merriweather Park at Symphony Woods, with major park features labelled. (Click for a higher-resolution version.) Image © 2014 Inner Arbor Trust; used with permission.

tl;dr: Now that construction of the Chrysalis is complete, what are the next steps to fulfill the vision of Merriweather Park at Symphony Woods?

This article is one in a series exploring in depth the creation of the Chrysalis amphitheater in Merriweather Park at Symphony Woods in Columbia, Maryland. For the complete list of articles please see the introduction to the series.

The previous few articles in this series discussed the design and construction of the Chrysalis itself. Now that construction of the Chrysalis is complete I take a look at what's next for Merriweather Park at Symphony Woods. In particular, this article focuses on other Merriweather Park features that are already part of the Site Development Plan approved by the Howard County Planning Board and are thus candidates for the next few years of park development.

Areas addressed in each phase (1 through 7) of the development of Merriweather Park at Symphony Woods. (Click for a higher-resolution version.) Image adapted from sheet 2 of SDP-14-073.

A roadmap for Merriweather Park at Symphony Woods

When the Inner Arbor Trust went before the Howard County Planning Board in November 2014, it sought approval not just for the Chrysalis amphitheater, but for a whole range of planned features for Merriweather Park at Symphony Woods—or at least the northern portion of it. (Recall that the Symphony Woods property also includes areas to the east, south, and west of Merriweather Post Pavilion.) In their combination of beauty and utility these features make Merriweather Park a more attractive destination for visitors and provide various key functions needed to accomodate them.

SDP-14-073, the Site Development Plan for Merriweather Park at Symphony Woods, outlines 7 phases of park development, with phase 1 being the construction of the Chrysalis and related infrastructure and phase 2 construction of an additional path connecting to the Chrysalis. In approving SDP-14-073 the Planning Board approved the design concepts, uses, and locations of park features for all 7 phases, and fully approved phases 1 and 2 for construction.

Each phase is tied to a particular area of Merriweather Park at Symphony Woods. The park features in each of the 7 phases are as follows:

The Chrysalis and related infrastructure, including an access road to the rear of the stage, a parking lot with 7 handicap spaces, and an accessible path from that parking lot to the Chrysalis.

A new park entrance at the corner of Little Patuxent Parkway and South Entrance Road, leading to the Chrysalis via an accessible boardwalk. This phase also includes the Sky Horns, a sound sculpture near the entrance (part of the Merriweather Horns public art) and restoration of the two streams on the eastern side of Merriweather Park.

The Butterfly guest services building and related infrastructure, including a rooftop terrace with lines of sight into both the Chrysalis and Merriweather Post Pavilion, and a large three-tiered deck facing the Chrysalis.

The Merriground play area and another new park entrance, from Little Patuxent Parkway across from the Mall in Columbia access road (to the west of the first park entrance). This phase also includes the Song Cycles, a second sound sculpture near the new entrance.

The Picnic Table and associated paths, including a third entrance to the park from Little Patuxent Parkway (to the west of the first two park entrances). This phase also includes the Land Horns, a third sound sculpture near the new entrance.

The Caterpillar and associated paths.

A renovated access road from Little Patuxent Parkway to Merriweather Post Pavilion, under the new name Free To Be Drive, along with a visitor drop-off area, a fourth park entrance, and the Tone Reeds, the fourth and final entrance sound sculpture.

The timing of phase 2 and beyond will depend on available funding, and the actual order of phases 3 through 7 may not be the same as that listed above.

All features listed above are discussed below, with the exception of Free To Be Drive and related vehicular roadways, parking spaces, and paths: much of that work has already been constructed by Howard Hughes Corporation under a later Site Development Plan (SDP-16-018) jointly submitted by Howard Hughes and the Inner Arbor Trust. (See also the last figure below.) Although paths, lighting, and elements of the Merriweather Horns will be constructed during their associated phases, for convenience they are discussed in separate sections.

Planned pathways within Merriweather Park at Symphony Woods, showing the materials used for the various paths and roads. (Click for a higher-resolution version.) This diagram does not show the accessible path that runs to the south end of the Chrysalis. Images © 2014 Inner Arbor Trust; used with permission.

The Merriweather Park path system

The plan for Merriweather Park at Symphony Woods includes over 2 miles of paths and walkable access roads and 4 separate pedestrian entrances into the park from Little Patuxent Parkway and Free To Be Drive, designed by landscape architects Mahan Rykiel Associates of Baltimore.

These paths and access roads will not all be constructed at once, but instead will be built incrementally as part of the various phases. For example, phase 1 (the Chrysalis) included construction of a walkable access road to the Chrysalis from the Merriweather Post Pavilion VIP parking lot, and an accessible path to the Chrysalis from a newly-built parking lot with 7 handicap spaces.

Phase 2 of the Site Development Plan includes construction of an accessible boardwalk from the Chrysalis to Little Patuxent Parkway. The planned boardwalk first heads west from the Chrysalis (skirting the existing stream to the north of the Chrysalis) and then goes northeast to the intersection of Little Patuxent Parkway and South Entrance Road, where the path will connect with the existing multi-use pathway leading to Lake Kittamaqundi. (See the two figures above.)

Additional paths will be constructed as part of the remaining phases, including adding two additional park entrances on Little Patuxent Parkway, one across from the access road to The Mall in Columbia, and one next to the existing access road from Little Patuxent Parkway to Merriweather Post Pavilion, and adding a fourth entrance from the future Free To Be Drive.

The pathways themselves are designed to be attractive, durable, and pervious to assist in handling storm water runoff. As it happens, the paths already constructed for the Chrysalis provide examples of all the planned pathway types:

Larger pedestrian areas, like the area in front of the Chrysalis alpha stage, will use permeable clay pavers (blue areas in the figure above).

Regular paths, like that leading to the Chrysalis from the 7-space handicap access parking lot, will use flexible pervious pavement made from recycled tire granules, aggregate rock, and a binding agent (green arrows in the figure above).

Boardwalks and decks, like the ramp leading to the Chrysalis stage, will be surfaced with ipe ("ee-pay"), an extremely durable and low-maintenance hardwood (red arrows in the figure above).

Walkable access roads, like that leading to the Chrysalis from the Merriweather Post Pavilion VIP parking lot, will be surfaced with asphalt and edged with cobblestones (purple areas in the figure above).

Any walls next to pathways (for example, as seen in the accessible path to the Chrysalis) will be constructed of stone from the region (yellow areas in the figure above).

Finally, the pathway system will provide plenty of opportunities for people to sit and take a rest, using seating built into the stone walls, long benches next to paths, circular benches, and circular bench and table combinations. Like the boardwalks and decks, these will be built using ipe hardwood. Altogether there will be seating for over 2,000 people.

Rendering of the Butterfly guest services building, as viewed from the Chrysalis looking southwest up the hill toward the Merriweather Post Pavilion VIP parking lot. (Click for a higher-resolution version.) Image © 2014 Inner Arbor Trust; used with permission.

The Butterfly

The Butterfly, designed by Mimi Hoang and Eric Bunge of the New York-based firm nARCHITECTS, is a guest services building containing café and gallery space, planned to be located between the Chrysalis and Merriweather Post Pavilion. Its main customer base will be people attending concerts and cultural events at either or both venues, supplemented by other visitors to the park. (The Butterfly will be open to the general public most of the time, except when ticketed events are being held at Merriweather Post Pavilion or the Chrysalis.)

In designing the Butterfly nARCHITECTS aimed for immersion, lightness, and connection: to immerse visitors in the natural setting, impart a sense of lightness to the structure, and connect it to both the Chrysalis and Merriweather Post Pavilion. One key element in promoting these goals is the design for the roof of the Butterfly. The roof is designed for active use by visitors: to watch performances at the Chrysalis or those held on the roof itself, or just to hang out with friends at the rooftop bar.

The roof will accomodate almost three hundred people, either standing or sitting on steps built into the upward curving wings of the roof. It will be reachable either by two exterior stairs or by an elevator within the Butterfly itself.

The ground floor of the Butterfly has four wings, housing food preparation areas, a small art gallery, and restrooms. The central space will have seating to accomodate patrons of the café. The Butterfly also has a three-level terraced outside deck facing the Chrysalis, again with seating to accomodate visitors.

The Butterfly can be entered from both the Merriweather Post Pavilion side (from the VIP parking lot) and the Chrysalis side (from the terraced deck), with glass walls providing a view through the building and a visual connection between the Merriweather Post Pavilion area and the woods leading to the Chrysalis—again promoting the goals of immersion, lightness, and connection.

Rendering of the Merriground. (Click for a higher-resolution version.) Image © 2014 Inner Arbor Trust; used with permission.

The Merriground

The Merriground, designed by Martha Schwartz Partners, is a children's play area containing multiple elements: a double helix spiral slide, a climbing tower and slide, various elements that can be used either for seating (at their lower levels) or climbing, a ring of rope swings, a "spider web" of rope that can be used as a hammock in which to relax, and—last but not least—the Wondrous Tower, a 45-foot-tall anodized aluminum tower within which visitors can ascend a spiral staircase and look out over the park.

The elements of the Merriground are custom-designed to have a common aesthetic and match the overall aesthetic of Merriweather Park at Symphony Woods: the elements incorporate circular and spiral shapes, and the wood used will be the same durable ipe hardwood used for the Merriweather Park boardwalk and decks.

The Merriground will be located on the boardwalk (from phase 2) that leads into Merriweather Park at Symphony Woods from the corner of Little Patuxent Parkway and South Entrance Road. It abuts the Lily Pads, a set of circular decks with benches that forms part of that boardwalk.

The Merriground thus not only serves as a play area, but also provides an attractive "entrance experience" for visitors arriving from the northeast, for example, walking from Lake Kittamaqundi on the multi-use pathway.

Rendering of the Picnic Table. (Click for a higher-resolution version.) Image © 2014 Inner Arbor Trust; used with permission.

The Picnic Table

The Picnic Table, also designed by Martha Schwartz Partners, has a very simple function: it takes an area of Merriweather Park at Symphony Woods that is low-lying and damp and turns it into an area that can be used for picnics, seating for events like Wine in the Woods, and just plain lounging around.

As its name suggests, the Picnic Table can be seen as an alternative to and replacement for conventional picnic tables. However, it can accomodate many more people within its expanse of 300 by 25 feet: over three hundred people can sit on or near the edge for an event like Wine in the Woods. The Picnic Table also has a much lower profile than conventional picnic tables: it is only 18 inches high, and is designed so that it appears to float above the ground below: the edges of the Picnic Table are cantilevered over 6 feet out from the relatively small steel columns and girders holding it up.

Finally, the Picnic Table is designed to fit into the landscape: it is covered with artificial turf to help it blend in to the underlying lawn, and has cutouts to avoid existing trees. (Seven new trees will also be planted to fill spaces within the existing tree cover.) The artificial turf and the underlying surface of the Picnic Table will also be perforated to allow water to drain naturally through the surface.

The development phase that includes construction of the Picnic Table will also see construction of a third pedestrian entrance into the park from Little Patuxent Parkway, and the Land Horns sound sculpture near the entrance. This accessible entrance will be west of the two other entrances, near the existing access road to Merriweather Post Pavilion and the future Free To Be Drive.

Oriented northwest to southeast, the Picnic Table itself runs roughly parallel to a section of this new path, and also roughly parallel to a separate path (on the other side of the Picnic Tables) constructed as part of the same phase as the Merriground. Visitors will thus have easy access to the Picnic Table from multiple segments of the park pathway system.

Rendering of the eastern end of the Caterpillar, providing access to the Chrysalis. (Click for a higher-resolution version.) Image © 2015 Inner Arbor Trust; used with permission.

The Caterpillar

The Caterpillar, designed by Martha Schwartz Partners, is the single most extensive feature proposed for Merriweather Park at Symphony Woods, about twice as long as the Picnic Table. It stretches over about a third of Merriweather Park from east to west, a circular tube covered with plants and other landscaping features.

Although it's designed to serve multiple functions, the Caterpillar's primary purpose is very simple: to provide an attractive visual and physical barrier between the "performance park" envisioned in the Inner Arbor concept plan (Merriweather Post Pavilion, the Chrysalis, and associated venues) and the "public park" (just south of Little Patuxent Parkway). This is in support of the twin principles of "operational elasticity" and "the art of bounds" pursued by the Inner Arbor Trust: to allow both the park and the pavilion to expand as needed to accomodate particular uses, and to ensure that the park can remain open to visitors even when events are held at the pavilion.

The striking design of the Caterpillar follows directly from these principles: a fence or wall would be too visually forbidding and unwelcoming for park visitors (as is the current fence around the Merriweather Post Pavilion property), while an earth berm of the needed height would be so wide that it would encroach upon the surrounding trees and suffocate their roots.

Essentially a tubular green wall, the circular cross-section of the Caterpillar allows for it to be large enough to provide physical separation between the two park areas while having a relatively small footprint on the ground below. At almost 11 feet high the Caterpillar is high enough to discourage visitors from climbing over it, but its rounded shape creates a more organic and visually friendly impression than a vertical barrier. Gateways at either end (where the Caterpillar structure arches over the paths) will funnel pedestrian traffic between the northern part of Merriweather Park and the southern part.

The Caterpillar does not follow the line of the existing fence on the property line between the Symphony Woods and Merriweather Post Pavilion properties. Instead it is located some distance north of the property line (towards Little Patuxent Parkway), with the area just south of the Caterpillar (towards Merriweather Post Pavilion) containing a pedestrian plaza and serving as an additional public area for visitors to the pavilion.

In addition to acting as an attractive visual and physical barrier, the Caterpillar also helps with the prosaic problem of providing utilities for events such as Wine in the Woods that spread beyond Merriweather Post Pavilion or the Chrysalis. The structure is hollow, designed to contain electrical lines, water lines, computer network cables, and anything else needed to support events in Merriweather Park at Symphony Woods.

The space immediately north and south of the Caterpillar can be used for event tents and other temporary structures, the fronts of which would face the paths and pedestrian plazas, and the backs of which would be next to any power or other utility outlets embedded in the Caterpillar. The Caterpillar can also support wireless access points to provide WiFi signals to a good portion of Merriweather Park at Symphony Woods.

The Caterpillar will also support a number of other uses: At either end it will contain information booths for visitors to the park or the pavilion. Since the structure supports potted plants as the main visual element it can be used as a community garden to raise flowers or herbs, and since it's intended to be lighted from within it can be used for visual art of various sorts.

Martha Schwartz has proposed other possible uses as well, including having "portals" through which people could view artworks or educational displays, supporting "audioscapes" either natural (e.g., activated by the wind) or artificial (using microspeakers), or having the structure interact with visitors via smartphone or tablet apps. The Caterpillar can thus serve as a platform for a myriad of possible uses, and will be one of the unique attractions of Merriweather Park at Symphony Woods.

Rendering of the Sky Horns at the northeast entrance to Merriweather Park at Symphony Woods (at the corner of Little Patuxent Parkway and the South Entrance Road). (Click for a higher-resolution version.) This rendering also shows a portion of the boardwalk by which visitors can reach the Merriground, the Chrysalis, and the rest of the park. Image © 2014 Inner Arbor Trust; used with permission.

The Merriweather Horns

As visitors enter Merriweather Park at Symphony Woods the Inner Arbor Trust wanted to make them feel that they were entering a special place. In support of that goal the Trust turned to a local artist with a national reputation, former Howard County resident William Cochran. The result was the Merriweather Horns, a set of sculptures for the entrances to Merriweather Park, as well as other sculptural elements to be located elsewhere in the park.

The Merriweather Horns are inspired by the ancient practice of producing sound via horns, from animal horns to musical instruments to the acoustic horns of old-time phonographs and audiophile speakers. As befits their inspiration, all of the pieces are designed to occasionally produce sounds of various types, soft enough to be heard only while standing near the sculptures, and muted during concerts held at Merriweather Post Pavilion or the Chrysalis.

Cochran designed one sculpture for each of the four entrances to Merriweather Park at Symphony Woods:

The Sky Horns will be located at the northeast entrance to Merriweather Park, at the intersection of Little Patuxent Parkway and South Entrance Road. They are a set of about a dozen long thin straight horns, from 6 to 23 feet in length, suspended among the trees and pointing down towards visitors entering the park on the boardwalk. (See the figure above.) Their sounds are designed to combine and evoke the human voice.

The Song Cycles will be located at the central entrance to Merriweather Park, at the bottom of the stairs leading down from Little Patuxent Parkway. Resembling traditional phonograph horns, two of them (terminating in fan wheels) are interactive sculptures: visitors can sit at them and use a set of bicycle pedals to produce a series of sounds from the sculptures. Pedalling faster changes the character of the sounds, until eventually they reach a crescendo and the cycle begins anew.

The Land Horns will be located at the northwest entrance to Merriweather Park, off Little Patuxent Parkway. They are a set of 6 large (up to 28 feet tall) horns, all but one with the bell part of the horn facing the ground. Five of the horns will produce a low frequency melody directed into underground acoustic chambers, with the other horn producing somewhat higher pitched sounds in harmony.

The Tone Reeds will be located at the southwest entrance to Merriweather Park, off the access road to Merriweather Post Pavilion from Little Patuxent Parkway (the future Free To Be Drive). They are a set of over 200 thin vertical rods ranging in height from 12 to 18 feet, positioned in a loose cluster several feet off the path. They produce a light delicate chiming sound.

In addition to the four main sculptures, there will also be about a dozen "pathfinder horns" at various points on the pathway system. These sculptures will serve as wayfinding devices, for example with two intertwined standing horns (from 8 to almost 10 feet tall) located at a fork in the path, each facing a different direction the visitor can take. The mouths of the horns will face down toward the visitor, with an interior gold finish covered by perforated stainless steel grilles with directional arrows and text.

The pathfinder horns will produce soft sounds characteristic of the forest and its underground wildlife. They can also be synchronized together to play a soft "evening song" melody to mark the end of the day.

Although they produce different sounds, all of the Merriweather Horns have a common visual aesthetic, combining white pearlescent fiberglass with stainless steel, designed to have a light appearance in a portion of the park that is in shade much of the time. The Merriweather Horns will also be lighted from within in various ways as part of the overall lighting scheme for Merriweather Park at Symphony Woods (see below).

The planting design for Merriweather Park at Symphony Woods. (Click for a higher-resolution version.) The lanscape in each numbered area will be restored with the appropriate plantings. Image © 2014 Inner Arbor Trust; used with permission.

Restoring the landscape in Merriweather Park

Although it's sometimes referred to as a preserved forest, after years of use and relative neglect the Symphony Woods property is not close to being in a natural state: most of the property is simply a lawn with accompanying trees, and even the more wooded parts of the property lack the understory plants one would find in a truly natural forest.

A key part of the plan for Merriweather Park at Symphony Woods is therefore to restore the woods to a more natural state while still making it possible for visitors to use the park on a day to day basis and during events like Wine in the Woods. The planting design was created by landscape architects Mahan Rykiel Associates, the firm that also designed the systems of paths in Merriweather Park, working with the Baltimore-based firm Biohabitats.

Mahan Rykiel has designated 5 different types of landscape in Merriweather Park at Symphony Woods, with each planned to be restored in a different manner (see the figure above):

Areas at the park entrances and next to many of the paths will have feature plantings: decorative bushes and shrubs (e.g., azaleas and rhododendrons), small trees, flowers, and the like. These will enhance the experience of visitors using the paths, beautify the outer edge of the park along Little Patuxent Parkway and Free To Be Drive, and form a natural complement to the Merriweather Horns.1

Areas to be used by visitors, for example the hill next to the Chrysalis and the areas around the Picnic Table and Caterpillar, will be restored as natural lawns.

Various areas in the more heavily forested eastern portion of the park will become enhanced woodlands, with native woodland plants (shrubs, perennials, groundcovers, and grasses) added to form a proper understory for the trees.

A relatively open area in the north of the park and another to the southwest will be converted into native meadows.

Finally, the streambeds in the eastern portion of the park will be restored and riparian buffers created between the streams and the rest of the park.

Rendering of the lighting master plan for Merriweather Park at Symphony Woods. (Click for a higher-resolution version.) Image © 2014 Inner Arbor Trust; used with permission.

Lighting Merriweather Park

The Chrysalis and Merriweather Post Pavilion will frequently host events in the evening. Visitors to Merriweather Park at Symphony Woods on those and other nights will want to be able to walk through the park and be able to find their way and have a sense of security. Proper lighting of the park is key to addressing these issues.

The New York office of Arup Associates, with Star Davis as lead, created the lighting master plan for Merriweather Park at Symphony Woods. The plan features multiple "layers" of lighting that work together to create an overall experience. The plan aims for the various lighting elements to have a natural quality, "as if growing from the earth and drawing power from the soil":

The first layer is lighting for the pedestrian pathways of Merriwweather Park. This will be provided by small fixtures near ground level spaced every 5 feet, designed to shine light on the path without bleeding light upward.

The second layer is lighting for vehicular roadways within Merriweather Park: access roads, parking lots, and visitor drop-off points. This will be provided by pole-mounted lights of various heights (each no higher than necessary given its location), facing downward to minimize light loss upwards.

The third layer is landscape lighting in Merriweather Park areas where people would be most likely to gather: between the Butterfly and the Chrysalis, at the Merriground and Picnic Table, and between the Caterpillar and Merriweather Post Pavilion. Some of these lights will be low to the ground (similar to the pathway lights), while others will be suspended among the trees.

The fourth layer is lighting for the Merriweather Horns, including both those at park entrances and the pathfinder horns located throughout the park. These will be softly lit from within.

The final layer is "integrated feature animation", that is, lighting of park features like the Merriground, Picnic Table, and Caterpillar that is designed to subtly change over time or in response to the actions of visitors.

Illumination throughout Merriweather Park will vary by layer and feature, designed to meet recommended light levels for various uses and contexts while not producing excessive or misdirected light. The overall effect of the lighting master plan will be to show all the features of Merriweather Park at Symphony Woods to their best advantages, making the park at night a magical experience for all its visitors.

Panoramic view of the areas of Merriweather Park at Symphony Woods addressed by phase 7 of SDP-14-073 and by SDP-16-018. (Click for a higher-resolution version.) The view is south-southeast toward Merriweather Post Pavilion, with the future Free To Be Drive in the foreground extending from the extreme left to the stop sign at the intersection with the future Merriweather Drive, the lower end of the drop-off loop to Merriweather Park and the new pavilion box office in the center (behind the small piece of construction equipment), and the new parking lot with handicap spaces in the center right (behind the row of barrels). Image © 2017 Frank Hecker; available under the terms of the Creative Commons Attribution 4.0 International License.

For further exploration

This article is based on material from a variety of online and offline sources, including the following:

For more on Martha Schwartz Partners, nARCHITECTS, and William Cochran, see the following:

Martha Schwartz Partners/Practice/Profile. From the Martha Schwartz Partners web site.

"Q&A with landscape architect Martha Schwartz". A Newsweek interview from March 11, 2015.

nARCHITECTS. nARCHITECTS web site.

"13 mins interview with Mimi Hoang - nARCHITECTS". An Arch20 interview from 2016 [?].

"Unabashed Designers of Delight" [121-minute video] (November 18, 2013). A presentation introducing the design team for the Inner Arbor plan. It includes a presentation by Martha Schwartz beginning at 12:00 and a presentation by Eric Bunge and Mimi Hoang beginning at 1:18:24.

"Studio William Cochran/Bios". Biographies of William Cochran and his wife and partner Teresa Cochran.

"William Cochran: changing streetscapes through public art", by Erik Anderson, May 18, 2016, Frederick News-Post. An article about Cochran's work in Frederick and beyond.

For more on the planned features for Merriweather Park at Symphony Woods, see the following:

By design/Community presentation. This page on the Merriweather Park web site features slides from the community presentation on December 2, 2013, including more renderings and design diagrams for the Caterpillar, Butterfly, and Picnic Table.

By design/The plan. This page on the Merriweather Park web site features a gallery of renderings of the Merriground and the Merriweather Horns.

SDP-14-073 (part 1, part 2, part 3, part 4, part 5). Although it can be difficult to read for the layperson, the approved Site Development Plan for Merriweather Park at Symphony Woods provides a wealth of detail about planned park features.

SDP-16-018. A subsequent Site Development Plan (jointly submitted by the Inner Arbor Trust and the Howard Hughes Corporation) describing elements that are part of phase 7.

For more on the plan for Merriweather Park at Symphony Woods as it has evolved from the original Inner Arbor plan, see the following:

The Inner Arbor pre-submission community presentation (December 2, 2013).

Michael McCall presentation to the Howard County Design Advisory Panel [20-minute video] (February 26, 2014). Among other things, this presentation outlines the principles of "operational elasticity" and "the art of bounds".

For more of my opinions on and explanations of various aspects of the Chrysalis and Merriweather Park at Symphony Woods, see the Inner Arbor-related posts in the series "The Inner Arbor plan takes shape" and elsewhere on this blog. (Note that some of these posts contain outdated information relating to park features that were later dropped or revised.)

Although the figure and the text refer to generic feature planting areas, as described in the Site Development Plan there are actually several distinct feature planting zones, each with a somewhat different mix of plants. See SDP-14-073 for the full list. ↩

Frank email@example.com that construction of the Chrysalis is complete, what are the next steps to fulfill the vision of Merriweather Park at Symphony Woods?Creating the Chrysalis: Attracting the public2017-04-11T08:00:00-04:002017-04-11T08:00:00-04:00https://civilityandtruth.com/2017/04/11/creating-the-chrysalis-attracting-the-public

Illustration of visitors to the completed Merriweather Park at Symphony Woods. (Click for a higher-resolution version.) The Chrysalis is in the background to the left, beyond the Caterpillar. Image © 2014 Inner Arbor Trust; used with permission.

tl;dr: I discuss how the Chrysalis and Merriweather Park at Symphony Woods can attract visitors, based on research conducted by Integrated Insight.

This article is one in a series exploring in depth the creation of the Chrysalis amphitheater in Merriweather Park at Symphony Woods in Columbia, Maryland. For the complete list of articles please see the introduction to the series.

The previous few articles in this series discussed the design and construction of the Chrysalis itself. There will be one more article discussing the final architectural details of the Chrysalis, but in the meantime before construction is completed I'll take a detour and discuss other aspects of Merriweather Park at Symphony Woods. In particular, this article focuses on how Merriweather Park might attract visitors and how many visitors could be reasonably expected once the park is built out, based on research conducted for the Inner Arbor Trust by Integrated Insight, Inc.

A sampling of attractions operated by Walt Disney Parks and Resorts, including theme parks, cruise ships, and resort hotels. (Click for a higher-resolution version.) Images © Walt Disney Co.

Integrated Insight and the real Disney magic

Over the 50 years that Symphony Woods has existed many people have proposed ways to encourage more visitors, from early attempts by the Columbia Association to promote Symphony Woods as a picnic area for families to CA's more recent efforts to formally develop the area as "Symphony Woods Park" (the so-called "Paumier plan"). However during that entire time few if any people made a serious effort to research exactly what types of park features might best attract visitors, and how many visitors might reasonably be expected as a result.

When the Inner Arbor Trust was given the responsibility of developing Symphony Woods as a park, one of its first actions was to commission exactly such a study. To perform the research the Trust turned to the Florida-based firm Integrated Insight, Inc.

Integrated Insight was founded in 2009 by Joni Newkirk, Scott Sanders, and other former executives of the Walt Disney Company. Newkirk had previously worked as a senior vice president responsible for researching, forecasting, and optimizing business for Walt Disney Parks and Resorts, the organization responsible for Walt Disney World, Disneyland, the Disney cruise line, and other Disney attractions around the world.

Jim Rouse was a fervent admirer of Walt Disney and his work in creating the Disney theme parks, once referring to Disneyland as "the greatest piece of urban design in the United States today …, [fulfilling] all its functions it set out to accomplish, un-self-consciously, usefully, and profitably to its owners and developers". Rouse's work in creating festival marketplaces like the Inner Harbor development in Baltimore can be seen as adapting various aspects of Disney's ideas to an urban setting.

Although Jim Rouse did not have the opportunity to work with Disney while at the Rouse Company, afterwards he explored creating a joint venture between the Walt Disney Company and the Enterprise Development Company, the for-profit arm of his nonprofit Enterprise Foundation. The lead on that project was Michael McCall, who was later to found Strategic Leisure, Inc., and then to spearhead development of Symphony Woods as president of the Inner Arbor Trust. McCall was thus familar with Disney's various projects, the executives responsible for them, and the capabilities that Disney had built in strategy and operations for its parks and resorts.

Those parks and resorts owe their success not just to the family-friendly image carried over from Walt Disney's animated films, but to the Walt Disney Company's application of sophisticated business practices to every aspect of running the parks: promoting the parks to potential visitors via various channels, forecasting park attendance to a high degree of accuracy, ensuring that visitors have a wide variety of park experiences available to them, engineering the layout and other aspects of the parks (including the lines for rides) to optimally accomodate visitors, and doing all this in a way that both delights visitors and is financially sustainable.

Joni Newkirk, Scott Sanders, and their colleagues played key roles in all of these areas. When they left Walt Disney Company to form Integrated Insight they brought with them a wealth of expertise in providing entertainment, travel and leisure organizations services including market research and consumer insights, forecasting and feasibility analysis, revenue and profit optimization, and capacity and operational planning. It was thus natural for Michael McCall and the Inner Arbor Trust to turn to Integrated Insight for advice on how to turn the Inner Arbor vision into a successful park.

Examples of attractions in the U.S. and elsewhere used for comparisons with the proposed Merriweather Park at Symphony Woods. (Click for a higher-resolution version.) Image © 2015 Inner Arbor Trust; used with permission.

Checking out comparable attractions

Integrated Insight first looked at the proposed Merriweather Park at Symphony Woods in the context of its likely market and of comparable and (in some cases) competitive attractions around the U.S. and beyond.

In doing this Integrated Insight (following the lead of the Inner Arbor Trust) considered the Symphony Woods property not in isolation but rather as integrated with Merriweather Post Pavilion: events at the pavilion will drive visits to the park, and features of the park will enhance the pavilion experience.

Integrated Insight also considered all the park features envisioned in the original Inner Arbor concept plan: not just the Chrysalis, but also other elements like a sculpture garden, a café, and so on. This recognized that the appeal of Merriweather Park at Symphony Woods for visitors will not be tied to any one park feature (just as, for example, visits to Disneyland aren't driven by any one attraction). Instead Merriweather Park's appeal will be a function of the total park experience.

As it turns out, some of the elements in the Inner Arbor concept plan are not part of the currently-approved plan for Merriweather Park at Symphony Woods, like the "treehouse" structures proposed as part of the elevated boardwalk. Others will likely be present, but not necessarily as part of Merriweather Park itself. For example, the proposed New Cultural Center on the Toby's Dinner Theater site next to the park will provide indoor performance venues similar to those proposed in the concept plan.

However, the overall principle remains sound: what will attract visitors is the overall experience of the Merriweather-Symphony Woods Neighborhood and related cultural attractions in the Merriweather District—Howard Hughes Corporation's term for the combination of the Merriweather-Symphony Woods Neighborhood and the Crescent Neighborhood surrounding it to the south and west.

There are 8 million people within 50 miles of Merriweather Park at Symphony Woods, an additional 6 million people between 50 and 100 miles away, and another 10 million people between 100 and 150 miles away—a total of 24 million within a 3-hour drive. These form the core markets for Merriweather Park, although it is also possible that visitors from further away will spend some time at the park while visiting the Baltimore or Washington DC area (e.g., as tourists or for family visits).

Thus Integrated Insight's list of comparable and competitive venues includes a mix of local attractions and more remote ones. For example, the Inner Arbor concept plan included a proposed sculpture garden south of Merriweather Post Pavilion. As part of the research study Integrated Insight looked at almost a dozen sculpture parks elsewhere in the U.S. and around the world, with park sizes ranging from less than 2 acres to over 1,000 acres, park entry fees of up to $12, and annual attendance from about 80,000 people to 1 million people.

These figures, along with the detailed descriptions in the research reports, provide some reasonable guidance on the possible appeal to visitors of a comparable sculpture garden within Merriweather Park at Symphony Woods, along with what it would take to make such a garden artistically and financially successful.

Integrated Insight performed similar research on other comparable and competitive features, including outdoor amphitheaters (comparable to Merriweather Post Pavilion and the Chrysalis), indoor venues (comparable to the indoor theaters proposed in the Inner Arbor concept plan and planned as part of the New Cultural Center), and events and festivals (comparable to Wine in the Woods and music festivals at Merriweather Post Pavilion). (See the figure above for the types of attractions covered, and a sample of those described.)

One comparison of particular interest is to "cultural districts", that is, areas within cities that feature multiple cultural attractions and are marketed as a single overall entity to prospective visitors. For example, the Pittsburgh Cultural District (overseen by the Pittsburgh Cultural Trust) covers 14 city blocks and features 7 theaters, 8 public parks and art installations, 12 art galleries, 50 restaurants and other places to dine, and 90 retail shops. In total the Pittsburgh Cultural District hosts 3,000 events and attracts 2 million visitors each year.

Again, this emphasizes that, just as the individual features within Merriweather Park at Symphony Woods should not be considered in isolation, Merriweather Park should not be considered in isolation from the broader downtown Columbia area, especially the Merriweather District south of The Mall in Columbia.

That area alone includes a host of cultural attractions existing, planned, and proposed, including the renovated Merriweather Post Pavilion, the Chrysalis and other features planned for Merriweather Park at Symphony Woods, the New Cultural Center planned for the Toby's Dinner Theater site, and a proposed new Central Branch library and a possible indoor music venue in the Crescent Neighborhood. If all of these are realized they will work in concert (no pun intended) to make downtown Columbia an attractive destination for both locals and visitors interested in culture and the arts.

Breakdown of participants in the Integrated Insight survey researching potential visitors to Merriweather Park at Symphony Woods. (Click for a higher-resolution version.) Image © 2015 Inner Arbor Trust; used with permission.

Surveying potential park visitors

In addition to researching comparable and competition attractions to Merriweather Park at Symphony Woods, Integrated Insight conducted a survey of 1,000 people to (among other things) further estimate the total market for Merriweather Park, determine what proposed park features, special events, and other aspects were most appealing to potential visitors, learn what revenue opportunities there might be for park attractions, and estimate how many people were likely to visit the park and its associated venues.

The survey included four groups of people: locals (within 10 miles of the park), residents (within 11-50 miles), mid-Atlantic tourists (recent visitors to the Washington DC/Baltimore area from various mid-Atlantic states, and distant tourists (recent visitors to the Washington DC/Baltimore area from other states). In addition, participants were screened to include only those who had participated in various cultural events (concerts, festivals, live theater, etc.) within the last two years, had visited parks or cultural venues (museums, art galleries, sculpture gardens, etc.) within the same timeframe, or expressed significant interest in such participation or visits.

As noted above, the purpose of the research was to gauge potential visitors' interest in Merriweather Park at Symphony Woods as envisioned in the Inner Arbor concept plan, not just the Chrysalis. Participants in the survey read a three-paragraph description of Merriweather Park ("In the middle of the Baltimore/Washington Corridor lies a beautiful and extraordinary escape, a forested culture park, founded in music and adorned with art…") and watched a video that included renderings of the proposed park features. They answered various questions to determine demographics, elicit their opinions on the park, and gauge the likelihood of their visiting it.

Some of the more interesting conclusions from the demographic survey were as follows, starting first with tourists:

Tourists are less affluent than locals (not surprising given the demographics of Howard County) and have a higher mix of families. Distant tourists are also relatively younger.

Most tourists to the Washington DC/Baltimore area are repeat visitors likely to be looking for new and interesting things to do.

Tourists have specific interests in cultural attractions, outdoor parks and performance venues, and festivals—all characteristics of Merriweather Park at Symphony Woods.

The overwhelming majority of visitors will have access to a car, and thus easy road access and parking for Merriweather Park will be an important factor in their willingness to visit.

Tourists participate in outdoor, cultural, and festival activities and have a high interest in continuing to do so. However attending concerts and live performances is not a primary driver of visits to Washington DC or Baltimore.

The vast majority of tourists do not plan their entire trip but leave at least some time open for last-minute activities. They also tend to drop 1 out of 4 planned activities from their itineraries. Together these mean that people are open to stopping by Merriweather Park for some reason or other, but their likelihood of visiting is stronger if they've already committed to visit (e.g., by buying tickets to a festival or other event).

Tourists have a lot of choices for activities in Washington DC and Baltimore. The majority of them have family in the area, and in many cases family members accompany them, so positive word of mouth and family endorsements will be key for attracting people to Merriweather Park.

Other findings with respect to locals and residents are as follows:

Locals and residents generally have similar interests to tourists. Locals and residents with families are more interested in participating in activities than those without, except for attending concerts and visiting art galleries (for which interest is comparable).

Awareness of Merriweather-related events is relatively low compared to awareness of nationally-recognized events like the Cherry Blosson Festival: no more than half of locals and residents were aware of Wine in the Woods, with even fewer aware of any of the various Merriweather Post Pavilion music festivals (Capital Jazz Festival, Virgin Freefest, etc.).

Nevertheless, significant numbers of locals and residents have attended performances at Merriweather Post Pavilion or Toby's Dinner Theater.

Percentages of survey respondents expressing strong interest (7-10 on a 10 point scale) in Merriweather Park at Symphony Woods as it's proposed to be built out. (Click for a higher-resolution version.) Image © 2015 Inner Arbor Trust; used with permission.

Public opinions on the proposed park

In addition to the questions about visits to and interests in atractions in the Washington DC/Baltimore area, the Integrated Insight survey also asked people their opinions about the proposed Merriweather Park at Symphony Woods. Those surveyed were asked to rate on a 10-point scale both their interest in attending an event at Merriweather Park and their interest in simply spending some time at the park. They were then asked to explain in their own words why they had rated their interest the way they did.

About two-thirds of all respondents indicated a strong interest (7-10 rating) in attending an event or just visiting the park. (See the figure above.) Of those indicating strong interest, reasons included the park sounding fun, being different and unique, providing outdoor activities, and providing entertainment.

Only 10% of all respondents indicated they had little interest (1-3 rating) in visiting Merriweather Park at Symphony Woods. The most common reasons for their low ratings were the distance they would have to travel (for example, for Virginia residents who would have to cross the Potomac River) and lack of interest in what the park had to offer. In general those with little interest were relatively older, were not living with other family members, and had less interest in attending live performances.

A significant fraction of respondents expressed extreme interest in both spending time at Merriweather Park at Symphony Woods and also attending events there (rating of 10 on both questions). The locals and residents expressing such extreme interest tended to be those who often hosted out-of-town visitors, more frequently attended performances at local venues, and more frequently visited The Mall in Columbia and a branch of the Howard County Library System.

The words survey respondents used to describe Merriweather Park at Symphony Woods were overwhelmingly positive: "great", "wonderful", "amazing", "fantastic", "spectacular", and so on. Only 5% of the words used to describe the park were negative (e.g., "boring" or "overdone").

The most appealing aspects of Merriweather Park were the outdoors aspect, the presence of multiple things to do, the events and performances, and the art and architecture. Almost half of all respondents could not name anything they did not find appealing. Of those who did name negatives the most frequently mentioned were distance, access, crowds, and parking—although it's worth noting that less than 5% of respondents expressed concerns about parking and traffic.

Overall the survey respondents came away with a strong positive impression of Merriweather Park at Symphony Woods. A question eliciting word impressions of the likely effect of the park on people produced responses like "merry", "happy", "free", and "relaxed", while two thirds or more strongly agreed with statements that Merriweather Park would be "a place to explore", "a place with diverse offerings", "green", and "a commmunity park I would be proud of". Almost as many people strongly agreed that Merriweather Park would be "a good fit for Maryland" and "a good fit for Columbia".

The survey also asked respondents to rate the appeal of 12 individual park features, including all the elements proposed as part of the original concept plan (like the Treehouse Skywalk) or added later (like the Merriground play area). The majority of respondents rated all park elements as highly appealing (8-10 on a 10-point scale). The 6 most popular features were the Treehouse Skywalk, Fountain Plaza, and sculpture garden (proposed in the concept plan), the Picnic Table and Caterpillar (part of the approved Site Development Plan), and Merriweather Post Pavilion itself.

Since this series has been focused on the Chrysalis, it's worth noting that the survey respondents found the Chrysalis to be a unique park element—84% could not name another venue it reminded them of. The most common responses from people referred to the Chrysalis as "amazing" or "great", and highlighted its relatively intimate scale, architecture, and setting; only a small minority did not like the Chrysalis.

The bottom line is that people responded most strongly to those proposed aspects of Merriweather Park at Symphony Woods that were most unlikely to be duplicated elsewhere—both unique events to attend (e.g., festivals and special performances) and unique park features that could be experienced during family outings. These aspects in turn increased the interest of those in the mid-Atlantic states and beyond in visiting the Washington DC/Baltimore area.

Estimated annual attendance for Merriweather Park at Symphony Woods once built out (including events at Merriweather Post Pavilion) compared to other U.S. attractions. (Click for a higher-resolution version.) Image © 2015 Inner Arbor Trust; used with permission.

Estimating park attendance

Finally, Integrated Insight used various questions combined with known attendance at existing destinations to estimate future annual attendance at the completed Merriweather Park at Symphony Woods.

The first step was to ask respondents to estimate how often they might visit, and what might draw them to the park. About half of locals and residents combined indicated they would likely visit at least a few times a year, with others indicating they would visit more often. As noted above, the most common reasons given for likely visiting were to attend specific performances or have a family outing.

Interest among tourists was also strong, with about three quarters of respondents indicating they would likely visit Merriweather Park at Symphony Woods if it were open while they were visiting. About half indicated their interest was strong enough they might plan a special visit to the area to visit Merriweather Park.

However expressed interest in visiting a place does not always translate into an actual visit. To get a better estimate, Integrated Insight started with the populations in the various groups of potential visitors (locals, residents, mid-Atlantic tourists, and distant tourists), reduced the population to include only that fraction expressing strong interest in visiting (from the survey results), and then for tourists further reduced it to include only those visiting the Washington DC/Baltimore area in the past year.1 This resulted in an estimated addressable market for Merriweather Park at Symphony Woods of about 30 million people.

Intergrated Insight then further adjusted its estimates to account for any overstatements respondents might have made regarding their intentions to visit the park. For example, if one took at face value the information provided by respondents regarding past visits to Merriweather Post Pavilion and extrapolated that to the size of the estimated addressable market, one would conclude that the pavilion had about 8 times more visitors per year than the actual attendance figures.

In other words, a more accurate estimate of projected attendance would be only about one-eighth or about 12% of what a naïve estimate might suggest—the so-called "overstatement factor" or "coefficient of overstatement". Integrated Insight did similar calculations comparing survey respondents' stated attendance at other venues compared to their actual attendance, and again obtained an overstatement factor of about 12%.

Integrated Insight used this overstatement factor in combination with other estimates (e.g., the number of potential venues at Merriweather Park at Symphony Woods, their respective capacities, and the likely number of events per year) to generate estimates on park attendance due to events. They also compared these estimates to actual attendance at comparable other venues (included those discussed above, like the Pittsburgh Cultural District) to see whether the estimates were reasonable.

At the same time Integrated Insight generated similar estimates for people who might visit the park outside of special events, including those visiting for family or school outings. These were also adjusted using the same overstatement factor of 12% used in adjusting attendance estimates for events.

The final estimate for attendance at a completed Merriweather Park at Symphony Woods was approximately 2.5 million visitors per year. This estimate includes attendees at Merriweather Post Pavilion and other performance venues, general park visitors (e.g., for walks and family outings), visitors for school graduations and other school-related visits, and people attending various special events (e.g., weddings or family reunions).

This level of attendance would make Merriweather Park at Symphony Woods one of the more popular attractions in the Washington DC/Baltimore area—not nearly as popular as (for example) the National Air and Space Museum, but significantly more popular than Washington DC attractions like the U.S. Botanic Garden and the Hirshhorn Museum and Sculpture Garden.

One problem presented by this level of attendance is how to accomodate visitors to Merriweather Park at Symphony Woods, especially during large events where a lot of visitors might want to leave all at once after the event is over. Integrated Insight assisted with this task as well, applying its experience in "industrial engineering" from the Disney parks and resorts to the proposed park pathway system.

For example, in its endorsement of the design of Merriweather Park at Symphony Woods, the Howard County Design Advisory Panel also recommended that the Inner Arbor Trust review the width of planned pathways within the park (shown in the figure below). Integrated Insight provided estimates on how many people would be able to exit the park within a given time (in this case, 800 people per hour for each foot of pathway width).

Based on these estimates the Trust revised its plans in order to widen certain pathway segments from 8 feet wide to 10 feet wide. The resulting pathway system, together with the entrance drive into the park off Little Patuxent Parkway, should be able to support the exit of more than 13,000 people going north within a 20-minute period. This will be more than sufficient for all but the very largest events, especially considering that traditionally most people have parked south of Merriweather Post Pavilion, not north, and that the 2,500-space parking garage planned to support the pavilion will also be to the south.

Integrated Insight thus applied its expertise to multiple aspects of Merriweather Park at Symphony Woods, bringing deep experience in park marketing and management to the long-desired goal of developing Symphony Woods into an attractive and popular park. The next article in this series will focus on future features planned for Merriweather Park, features that will help round out the vision of the park that Integrated Insight's survey respondents found so attractive.

The proposed paths for Merriweather Park at Symphony Woods, classified according to size and accessibility. (Click for a higher-resolution version.) This diagram does not show the later increase in width from 8 feet to 10 feet on certain paths. It also does not show the addition of another accessible path running to the southern end of the Chrysalis. Image © 2014 Inner Arbor Trust; used with permission.

For further exploration

This article is based on material from a variety of online and offline sources, including the following:

For more on Integrated Insight, its history and team, and its work on the Merriweather Park project, see the following:

Integrated Insight, Inc.: Management consulting [PDF], July 2014. A presentation of Integrated Insight's executive team and their background, its areas of expertise, and representative projects.

Merriweather Park at Symphony Woods: Market regions and comparative analysis [PDF], December 7, 2014. A presentation discussing the regions from which Merriweather Park would likely draw most of its visitors, and presenting information about other venues in the U.S. and elsewhere with comparable attractions and appeal.

Merriweather Park at Symphony Woods: Product research and demand study (part 1, part 2, and part 3) [PDF], December 15, 2014. A presentation discussing the results of a public opinion survey concerning Merriweather Park and an analysis of potential annual attendance.

"Math of Architecture, Architecture of Math" [67-minute video]. An event on November 3, 2015, sponsored by the Inner Arbor Trust to promote the Chrysalis project. Includes a presentation by Joni Newkirk starting at 10:40, discussing Integrated Insight and its research.

Letter from Michael McCall to Randy Clay, March 14, 2014. A letter responding to the Howard County Design Advisory Panel's request to the Inner Arbor Trust to review the widths of the planned pathways within Merriweather Park at Symphony Woods.

For more on the Chrysalis amphitheater and its origins in the Inner Arbor concept plan, see the following:

Michael McCall presentation of the Inner Arbor concept plan to Leadership Howard County [33-minute video] (September 20, 2013).

The Chrysalis portion of the Inner Arbor pre-submission community presentation (December 2, 2013).

Michael McCall presentation to the Howard County Design Advisory Panel [20-minute video] (February 26, 2014).

For more of my opinions on and explanations of various aspects of the Chrysalis and Merriweather Park at Symphony Woods, see the Inner Arbor-related posts in the series "The Inner Arbor plan takes shape" and elsewhere on this blog. (Note that some of these posts contain outdated information relating to park features that were later dropped or revised.)

More correctly, Integrated Insight took the fraction of tourists who had visited the Washington DC/Baltimore area in the last 2 years, and divided that fraction by 2. ↩

Frank firstname.lastname@example.com discuss how the Chrysalis and Merriweather Park at Symphony Woods can attract visitors, based on research conducted by Integrated Insight.Creating the Chrysalis: Subfloor and related construction2017-03-18T11:00:00-04:002017-03-18T11:00:00-04:00https://civilityandtruth.com/2017/03/18/creating-the-chrysalis-subfloor-and-related-construction

Rendering of the reinforced concrete integrated foundation/basement system or "subfloor" to which the Chrysalis steel frame is attached. (Click for a higher-resolution version.) Most of this structure is underground. Compare to the first figures of the two previous articles of this series. Image © 2015 Arup; used with permission,

tl;dr: I present more details on the Chrysalis integrated foundation/basement system ("subfloor") and other construction at the Chrysalis site, featuring the work of Whiting-Turner.

This article is one in a series exploring in depth the creation of the Chrysalis amphitheater in Merriweather Park at Symphony Woods in Columbia, Maryland. For the complete list of articles please see the introduction to the series.

The previous two articles in this series discussed the fabrication and installation of the steel frame and skin of the Chrysalis. This article presents more information on the construction of the structural concrete integrated foundation/basement system (also known as the "subfloor") to which the steel frame is attached. It features the work of the Whiting-Turner Contracting Company of Towson, Maryland.1

The Teachers Building at 10221 Wincopin Circle (completed 1967), constructed by Whiting-Turner as the first office building in Columbia, Maryland. (Click for a higher-resolution version.) Image © 2017 Frank Hecker; available under the terms of the Creative Commons Attribution 4.0 International License.

Whiting-Turner

As discussed in the previous article, for the steel frame and aluminum shell of the Chrysalis the Inner Arbor Trust used A. Zahner Company as the "design-build" contractor. For the remainder of the Chrysalis construction, including construction of the reinforced concrete structural "subfloor" that serves as a robust foundation beneath the Chrysalis stage, the Trust followed the more traditional "design-bid-build" process. After competitive bidding the Trust selected as general contractor the Whiting-Turner Contracting Company of Towson, Maryland.

Like Zahner, Whiting-Turner is a private company with a heritage that reaches back over a hundred years. It was founded in 1909 in Baltimore, Maryland, by G.W.C. Whiting, a Baltimore native and recent graduate in civil engineering from the Massachusetts Institute of Technology, and his classmate LeBaron Turner. Turner left the company after five years, but Whiting continued his association with the company until his death in 1974 at the age of 91.

In its early days Whiting-Turner bid on contracts for paving roads and laying sewer pipes. In the 1920s it took on bigger projects, including the elevation of Loch Raven Dam in Baltimore (completed 1922) and the construction of various bridges. (Whiting-Turner later did work on both the Chesapeake Bay Bridge and the Delaware Memorial Bridge.)

1938 saw Baltimore native and Johns Hopkins engineering graduate Willard Hackerman join Whiting-Turner. After rising through the ranks Hackerman replaced G.W.C. Whiting as president in 1955, and remained in that position until his death in 2014 at the age of 95. (His replacement was current president and CEO Timothy Regan.) During Hackerman's tenure Whiting-Turner literally changed the face of Baltimore, constructing (among others) Meyerhoff Symphony Hall, the National Aquarium, M&T Bank Stadium (home of the Baltimore Ravens), and (last but not least) Jim Rouse's Harborplace development.

Closer to home, Whiting-Turner constructed the Teachers Building (completed 1967), the first office building in Columbia and the former headquarters of the Columbia Association. Whiting-Turner also built the Columbia Mall (completed 1971) and oversaw its later expansion and renovation as The Mall in Columbia (completed 1999).

Whiting-Turner's involvement with Columbia is thus as old as the city itself, and its work on the Chrysalis marks 50 years of Whiting-Turner projects in downtown Columbia.

The Chrysalis construction site in the early stages of site preparation and grading. (Click for a higher-resolution version.) Note the cistern under construction at the back of the site. (See also the figure below.) Image © 2015 Inner Arbor Trust; used with permission.

Preparing the Chrysalis site

Whiting-Turner's role in the construction of the Chrysalis encompassed more than just the construction of the foundation/basement: they were ultimately responsible for tree protection, stormwater management, site utilities, electrical, plumbing and HVAC systems, roads and paths, and general site work—things that most users of the Chrysalis will likely not consciously notice, but which are critical to ensuring the safety, stability, and functioning of the Chrysalis as a whole.

As the general contractor Whiting-Turner selected and oversaw subcontractors who carried out these various tasks. However in the end it was Whiting-Turner's work in coordinating the many details of construction and holding subcontractors to high standards of quality that would make the difference in bringing the project to a successful conclusion. This work was overseen by Whiting-Turner vice president (and Howard County resident) Jeff Cooper, project manager Peter "Tyge" Sheehan, and assistant project manager Sam Grayman.

After the Chrysalis groundbreaking in September 2015, Whiting-Turner established its on-site office and commenced preparing the site, once the Inner Arbor Trust had received a grading permit from Howard County. (This was separate from the building permit, which was issued later.)

Appropriately, given the concern expressed by many regarding the trees of Symphony Woods, Whiting-Turner's first task was to ensure the health of trees near the construction area. In pursuit of this they hired a professional arborist to survey the trees in the vicinity and create a comprehensive plan to protect them. This included pruning the roots of trees next to areas scheduled to be excavated, placing mats to protect specific critical root zones, and doing nutrient feeding for certain key trees.

There is a small stream to the north of the Chrysalis and behind the Chrysalis to the east (toward South Entrance Road). In order to limit runoff and prevent construction debris from entering the stream buffer area, "super silt" fencing (filter fabric backed by chain link fencing) was placed around the construction area.

The next task was the construction of a new 8-inch water line to the Chrysalis site itself and to the Chrysalis service road (which runs from the Merriweather Post Pavilion VIP parking lot to the back of the Chrysalis). This water line serves fire suppression sprinklers in the Chrysalis itself, and supplies two new fire hydrants at the beginning and end of the Chrysalis service road. The line will also supply drinking water for general purposes in and around the Chrysalis, and provide water to subsequent phases of Merriweather Park at Symphony Woods.

The construction of the water line illustrates the complications of land ownership in the Merriweather-Symphony Woods neighborhood. The source of the water for the new water line is an existing water main in South Entrance Road, and the new line passes under Symphony Woods Road, a private road owned by the Howard Hughes Corporation. Howard Hughes provided the Inner Arbor Trust an easement to make such a connection as part of a wide-ranging reciprocal easement agreement concluded between the two parties.

The underground cistern behind the Chrysalis under construction. (Click for a higher-resolution version.) The two vertical pipes (along with another not yet installed) were capped with manhole covers once the cistern was covered and the overlying surface paved. Image © 2015 Inner Arbor Trust; used with permission.

The Chrysalis cistern

As evidenced by the July 2016 flash flood in Ellicott City, heavy rainstorms can result in very large quantities of runoff, especially when the rain falls onto impervious surfaces such as roads and buildings. A key task in construction, undertaken even before excavating the site, was therefore putting in place permanent measures to handle runoff into the nearby stream, particularly from the 12,000 square feet of the Chrysalis shell canopy—a pleated surface that acts as a very large rain gutter over the approximately 5,000 square feet of the Chrysalis stage.

On many building sites ponds are constructed to retain runoff prior to releasing it into the surrounding watershed. Aesthetic considerations and the limited area of the site required a different solution for the Chrysalis: instead of a pond Whiting-Turner installed an underground cistern, constructed of large corrugated metal pipes 5 feet in diameter and capable of storing almost 2,500 cubic feet of water in total (over 18,000 gallons).

The pleats of the Chrysalis shell carry rainwater and snow melt to the base of the nine shell legs where the canopy comes to the ground. At the base of each leg stormwater drains through beds of landscaping stone that sit on galvanized steel grates that top underground basins. The basins (resembling concrete bathtubs) then funnel the runoff into a network of underground pipes that empty into the cistern.

The runoff accumulates in the cistern until the cistern reaches its design capacity, at which point the cistern begins to release water into the stream system. The overall effect is to even out the flow of water and reduce high-velocity surges during severe downpours. This reduces the harmful effects of both local erosion of the stream bed and downstream sedimentation as the runoff proceeds into the Little Patuxent watershed.

Pouring a concrete "mud mat" in preparation for constructing the walls of the structural subfloor. (Click for a higher-resolution version.) The view is from the front of the Chysalis (stage right of the alpha stage) looking southeast. A completed mud mat is in the foreground, with previously-installed utility conduits running under the completed mat and the one being poured. Image © 2015 Inner Arbor Trust; used with permission.

Site excavation and mud mats

After the cistern was installed Whiting-Turner began the mass excavation of the Chrysalis foundation/basement, preparing the site for the foundation construction and for installation of underground utilities, including conduits for supplying electricity to the theatrical lighting and audio systems.

The Chrysalis construction site was designed as closely as possible to be in a "net zero fill" condition. In other words, earth that was removed during the initial stages of construction was saved and then redeployed later in the construction process, instead of being hauled away. This was more cost efficient and also resulted in a lower carbon footprint for the construction as a whole.

As part of this process dirt and small stones were stockpiled on-site and covered with plastic for future use in backfilling the inside and outside of the Chrysalis foundation walls. Larger stones that could not be used for fill were removed by Whiting Turner's subcontractor, Highland Turf, Inc., and moved to other locations within the Merriweather-Symphony Woods and Crescent neighborhoods, for use by the Howard Hughes Corporation in its own stream restoration projects.

Once the foundation was excavated, workers poured concrete "mud mats" (also known as "mud slabs") following the outline of the Chrysalis's exterior and interior walls. The mud mats served as a non-structural "foundation for the foundation", providing a solid flat surface upon which reinforcing steel bars (rebar) and wooden molds for concrete (formwork) could be placed, and the concrete for the subfloor's walls then poured.

Rebar in place prior to completing the wooden formwork and pouring concrete for the subfloor walls and piers. (Click for a higher-resolution version.) The view is from the front of the Chrysalis (stage right of the alpha stage) looking northeast. The heavy concentrations of rebar to the left and elsewhere are for the concrete piers to which the legs of the Chrysalis steel frame are attached. Note the two layers of rebar for the exterior wall, as well as the use of orange "rebar caps" to protect workers from exposed rebar. Image © 2015 Inner Arbor Trust; used with permission.

Reinforced concrete

Once the mud mats were poured, workers placed reinforcing steel bars or rebar in preparation for constructing the exterior and interior walls of the subfloor foundation.

First used extensively in the 19th century and perfected in the 20th, reinforced concrete is ubiquitous in modern construction. It works by combining the compressive strength of concrete with the tensile strength of steel—in other words, the concrete resists being pushed together and the steel resists being pulled apart. With the two bonded together in a composite, the resulting material resists loads placed on it without bending or breaking.

The reinforced concrete used in the Chrysalis is "cast in place" concrete: A mesh or "mat" of rebar was laid on top of the previously-poured mud mats, tied together, and inspected. The rebar was laid especially densely in areas designed to bear heavier loads, such as the concrete piers to which the legs of the Chrysalis steel frame are attached. (See the figure above.)

Wooden modular paneled formwork was then constructed around the rebar to act as a mold, and high-strength "5,000 psi" concrete poured into the formwork and around the rebar.2 As the concrete cured it bonded to the steel bars (rebar is typically corrugated to make this bond stronger), giving the resulting walls or piers their strength.

Laying the rebar, constructing the formwork, and pouring concrete was made more complicated by the irregular shape of the Chrysalis foundation: looking at the structure from above (in so-called "plan view") there are only four 90-degree angles apart from the stairs. In all other places the formwork needed to be carefully framed to correspond to the curves in the exterior walls and piers.

Exterior wall of the Chrysalis subfloor after pouring concrete, and wooden formwork for the interior walls. (Click for a higher-resolution version.) The view is from the front of the Chrysalis (stage right of the alpha stage) looking southeast. The wall to the right is the same as shown in the foreground in the previous figure, while the pier in the center is the same as that shown in the left of the previous figure. Image © 2016 Inner Arbor Trust; used with permission.

The foundation/basement walls and ceiling

In January 2016 construction of the Chrysalis was interrupted by the "Snowzilla" storm. After the storm was over and snow cleared from the site, the first major concrete pour of the foundation was successfully made, by Whiting-Turner's subcontractor McGuire Concrete. First to be poured were the 8-inch-thick exterior walls and the associated concrete piers for attachment of the steel frame of the Chrysalis.

The exterior walls were reinforced with #3 and #5 rebar placed every 6 inches, laid crossways in two layers.3 The piers were reinforced with a larger size of rebar, laid so densely that special accomodations had to be made to fit in the anchor bolts to which the legs of the steel frame were attached.

(Special care was taken in surveying where to place these bolts, in order to position them as accurately as possible for connecting to the steel frame. The bolt positions were surveyed twice before pouring the concrete, and then surveyed again immediately afterward to ensure that the pouring operations had not disturbed them.)

Subsequently three interior walls were poured (also 8 inches thick, and similarly reinforced), running in parallel lines from the front of the Chrysalis to the back. These walls formed two interior rooms of a walkout basement, one to be used for electrical equipment providing 2,000 amps to the stage, and the other to be used for storage of Chrysalis-related equipment—almost 1,600 square feet in all.

In the back of the Chrysalis Whiting-Turner and its subcontractors constructed three sets of concrete stairs leading from ground level to stage level, for the use of performers, stagehands, and others. (Between the stairs is a loading dock with a space for a so-called "scissors lift" to lift equipment from the dock to the stage.)

Once the interior walls were complete, the two basement rooms were covered with a 10-inch-thick slab of reinforced concrete, poured into formwork supported from below, with two layers of #5 rebar placed every 6 inches each way. This slab forms the ceiling for the basement rooms and a portion of the concrete floor for the stage.

The remaining spaces outside the two rooms were then filled with dirt saved from the earlier excavation, topped with a layer of gravel, and then capped with 10-inch-thick slabs of reinforced concrete to match up with the slab over the basement rooms. All of these slabs tied directly into the walls and piers, using rebar exposed for this purpose. (See the figure below.)

In total about 550 cubic yards of high-strength 5,000 psi concrete went into the structure. The concrete was reinforced by over 100,000 pounds of rebar.

Workers preparing wooden formwork in preparation for pouring one of the reinforced concrete slabs forming the top of the subfloor. (Click for a higher-resolution version.) The view is from the front of the Chrysalis looking east. The pier to the left is the same as that shown in previous figures. Note the exposed rebar on the perimeter walls, the piers, and the already-poured slab over the basement, as well as the utility conduits at the left. Image © 2016 Inner Arbor Trust; used with permission.

The structural diaphragm

As previously discussed, all of these elements form what structural engineers call a "diaphragm", integrating the vertical foundation walls and piers together with the horizontal floor into a single, strong structural whole. This is the same principle that makes a soup can much stronger with one of its lids fully attached to its cylinder, as the lid acts as a diaphragm, transferring forces exerted from one point throughout the rest of the can. The result is a strong rigid structure that can easily support the steel frame of the Chrysalis and the attached shell, and help the Chrysalis resist the various loads placed upon it.

Whiting-Turner's role in constructing the Chrysalis did not end with the completion of the subfloor. As a general contractor its work is not finished until the completed Chrysalis structure and all related elements—railings, roads, pathways, etc.—are handed over to the Inner Arbor Trust. Discussion of the remaining elements, including some not yet finished at the time of writing, is deferred to a future article on the architectural details of the Chrysalis and the lansdcaping of its surroundings.

Workers pouring concrete for the stairs at the back of the Chrysalis. (Click for a higher-resolution version.) The worker to the left is standing on one of the reinforced concrete piers of the Chrysalis; to the right are the doors leading into the two basement rooms of the subfloor. Image © 2016 Inner Arbor Trust; used with permission.

For further exploration

This article is based on material from a variety of online and offline sources, including the following:

For more on Whiting-Turner, its history, its work on the Chrysalis project, and related topics, see the following:

Whiting-Turner portfolio of selected projects and areas of expertise.

"Whiting-Turner History". Historical timeline on the Whiting-Turner web site.

"G.W.C. Whiting rites tomorrow", page A17, Baltimore Sun, November 19, 1974. Obituary for G.W.C. Whiting.

"Construction Magnate and Philanthropist", by Jacques Kelly, page A1, Baltimore Sun, February 11, 2014. Obituary for Willard Hackerman.

"Building Occupancy", page F10, Baltimore Sun, September 17, 1967. Announcement of the opening of the Teachers Building in Columbia.

"Work Sped On Columbia Mall for Tomorrow's Opening", by Carleton Jones, page F1, Baltimore Sun, August 1, 1971. An article on the opening of the Columbia Mall.

"New wing of The Mall opens with a flourish", by Jill Hudson Neal, page 14B, Baltimore Sun (Anne Arundel edition), September 19, 1999. The opening of a new wing of The Mall in Columbia after the mall's renovation and expansion.

Inner Arbor Trust construction updates for September 2015, October 2015, November and December 2015, January and February 2016, March 2016, and April 2016. Ongoing updates describing the progress of the construction of the Chrysalis.

"Chrysalis steel and concrete construction". A collection of photographs (and a video) showing the progress of the construction of the Chrysalis.

"Reinforced concrete". A Wikipedia article describing the history and use of reinforced concrete.

For more on the Chrysalis amphitheater and its origins in the Inner Arbor concept plan, see the following:

Michael McCall presentation of the Inner Arbor concept plan to Leadership Howard County [33-minute video] (September 20, 2013).

The Chrysalis portion of the Inner Arbor pre-submission community presentation (December 2, 2013).

Michael McCall presentation to the Howard County Design Advisory Panel [20-minute video] (February 26, 2014).

For more of my opinions on and explanations of various aspects of the Chrysalis and Merriweather Park at Symphony Woods, see the Inner Arbor-related posts in the series "The Inner Arbor plan takes shape" and elsewhere on this blog. (Note that some of these posts contain outdated information relating to park features that were later dropped or revised.)

Portions of this article were adapted (with permission) from the construction updates published by the Inner Arbor Trust. (See the section "Further exploration".) ↩

The strength of concrete is measured in terms of the amount of load it can bear without breaking, as measured in pounds per square inch, with more high-strength mixes costing more. Garden-variety applications like sidewalks typically use less-expensive 3,000 psi concrete. ↩

The designations used in the U.S. for rebar correspond to the approximate diameter of the rebar in eighths of an inch. Thus #3 rebar is ⅜ inches in diameter, #5 rebar ⅝ inches in diameter, and so on. ↩

Frank email@example.com present more details on the Chrysalis foundation/basement or "subfloor" and related construction, featuring the work of Whiting-Turner.Creating the Chrysalis: Shell skin2017-03-04T10:30:00-05:002017-03-04T10:30:00-05:00https://civilityandtruth.com/2017/03/04/creating-the-chrysalis-shell-skin

Rendering of the ZEPPS® profiles underlying the shingles of the Chrysalis skin. (Click for a higher-resolution version.) Compare to the first figure of the previous article in this series. Image © 2015 Arup; used with permission.

tl;dr: I explain how the skin of the Chrysalis was fabricated and installed by A. Zahner Company.

This article is one in a series exploring in depth the creation of the Chrysalis amphitheater in Merriweather Park at Symphony Woods in Columbia, Maryland. For the complete list of articles please see the introduction to the series.

The previous article in this series discussed the steel frame that underlies the skin of the Chrysalis and enables the Chrysalis to support theatrical, wind, and other loads. This article explains how the complex and dynamic topography of the Chrysalis shell was made real, and how the colored aluminum shingles forming the skin of the Chrysalis were fabricated and attached to that topography. It features the work of A. Zahner Company of Kansas City, Missouri.

Aerial view of the Museum of Pop Culture, formerly the Experience Music Project Museum, in Seattle, Washington. (Click for a higher-resolution version.) Image © 2008 EMPISFM; used under the terms of the Creative Commons Attribution-Share Alike 3.0 Unported license.

A. Zahner Company

In typical construction practice a building is first designed and then contractors submit bids to do the actual construction—the so-called "design-bid-build" process. This process assumes that once a suitable design has been created any contractor will suffice to construct it, as long as they are suitably competent at their trade.

However, given its unusual design the Chrysalis is far from being an ordinary building; the typical contractor would be at sea trying to figure out how to build it. Thus for the Chrysalis shell (i.e., everything above the relatively conventional structural concrete subfloor) the Inner Arbor Trust instead followed the "design-build" paradigm, in which a single contractor bears responsibility for the detailed design of the structure and all phases of its construction. That single contractor was A. Zahner Company of Kansas City, Missouri, commonly known as "Zahner".

How did Zahner come to be given this task? Its origin dates to the turn of the 20th century: Andrew Zahner, the son of a German immigrant, started a small business in Missouri that made metal cornices for buildings, tin ceilings, and metal ductwork for heating systems—one of hundreds of similar businesses across the United States. His son Leo Zahner and his grandson Leo Zahner, Jr., continued to operate it as a local Kansas City business under the names A. Zahner & Company and A. Zahner Sheet Metal Company.

After Leo Zahner, Jr., returned from serving in World War II he expanded Zahner's work in so-called "architectural metal" products, including metal roofs, decks, siding, and façades. The year 1958, when his son Bill was still a toddler, saw A. Zahner & Company put in the lowest bid to replace the roof of the Liberty Memorial museum in Kansas City (now the National World War I Museum and Memorial), for a total price of $2,293—only $1,998 if Zahner were allowed to keep the copper panels from the old roof.

Zahner's evolution from a local and regional business began after Bill Zahner graduated from college and joined the company. Although he majored in civil engineering, Bill Zahner was and is as much an artist as an engineer, including working as an amateur sculptor. Just as in the 1930s Ove Arup became enthused about modern architecture and its use of reinforced concrete, in the 1980s Bill Zahner became excited about the possibilities of using architectural metals in contexts beyond the mundane—going so far as to later write two books on the topic.1 He began promoting Zahner's capabilities at national industry trade shows and reaching out to visionary architects like Frank Gehry (then relatively unknown).

Bill Zahner's artistic bent was key to how Zahner evolved as a company and conceived of its mission. After he became the president of Zahner in the late 1980s, the soon-renamed A. Zahner Company began working on projects with ever higher profiles and ever more difficult challenges, like the American Heritage Center in Laramie, Wyoming (completed in 1993), with its distinctive dark copper roof, or the Museum of Science and Industry in Tampa, Florida (completed in 1995), with its doubly-curved stainless steel roof.

Bill Zahner's friendship with Frank Gehry also bore fruit in a series of projects, including a 1988 exhibit for the 100th anniversary of the Sheet Metal Workers International Association, a collaboration for the Weissman Art Museum in Minneapolis (completed in 1993), and then, and most significantly, in the creation in Seattle of the Experience Music Project (completed in 2000), a museum funded by Microsoft co-founder Paul Allen.

ZEPPS panels installed on the steel frame of the Chrysalis prior to installation of the shingles. (Click for a higher-resolution version.) The triangles formed by the secondary steel were later filled in with ZEPPS panels fabricated on site, while gaps between the prefabricated panels were later covered by anodized aluminum sheet metal. Compare to the figure below. Image © 2016 Inner Arbor Trust; used with permission.

Engineering for uniqueness

The Experience Music Project Museum (now known as the Museum of Pop Culture) posed challenges well beyond those of previous Zahner or Gehry projects. The building featured a radically curved set of exterior metal surfaces in both stainless steel and aluminum, with almost all parts of the surfaces required to be unique in some way. (See the figure above.)

In solving the problem of how to marry such surfaces to the underlying building structure, Zahner invented the Zahner Engineered Profile Panel Systems, or ZEPPS®. The ZEPPS process was made possible by the same technological trends later leveraged by Marc Fornes and his colleagues, including in particular the development of advanced 3D modeling software and its ability to interface to machine tools via Computer Numeric Control (CNC).

Zahner used these technologies to simplify the task of fabricating and installing the complex metal surfaces by reducing them to a set of customized individual panels, each of which could be separately fabricated and installed onto the building structure. The ZEPPS process and related technologies formed the basis of Zahner's growth in both revenue and reputation in the 21st century.2 The fifth generation ZEPPS process was key to creating the Chrysalis.

A map of how the prefabricated ZEPPS panels were installed in the Chrysalis steel frame. (Click for a higher-resolution version.) AB, EB, GB, HB, IB, LB, OB, PB, and PB mark the bottom of the nine legs of the Chrysalis, for which ZEPPS panels were fabricated on-site. Compare to the figure above. Image © 2016 A. Zahner Company; used with permission.

Designing ZEPPS panels

Viewed in isolation an individual ZEPPS panel is a relatively prosaic object: a set of pieces of aluminum (referred to as "profiles", and resembling trusses or purlins in traditional structures), with one side of each profile attaching to the underlying structure and the other side attaching to a sheet of metal forming part of the exterior surface.

The true sophistication of the ZEPPS process is apparent only when contemplating a collection of ZEPPS panels fabricated for a particular structure, and the underlying computer technology that makes their fabrication and installation possible: In a structure like the Experience Music Project Museum or the Chrysalis each and every part of the exterior metal surface may have a different degree of curvature, may be curved in two directions and not just one, may attach to the underlying structure at different angles, may impose a different set of loads, and may need customized instructions for how to install it.

Zahner designs ZEPPS panels using the CATIA software discussed in a previous article: given a 3D model of the underlying structure and a 3D model of the desired metal surface, Zahner determines how many ZEPPS panels are needed, what shapes they must take, and other characteristics. For example, the individual profiles within a panel must be spaced at a suitable distance in order to bear the weight of the metal skin. Based on the loads imposed on the ZEPPS panels, they may also be made out of slightly different material, for example, lower-strength aluminum vs. higher-strength aluminum.

In some cases the underlying structure itself may need to be modified somewhat in order to account for the need to fit panels together in a certain way, for example, for ease of installation. This was required for the Experience Music Project Museum, among others, and helps explain Zahner's typical practice of working very closely with the architect and often taking the role of a design-build contractor. Finally, since ZEPPS panels are typically fabricated at Zahner's shops, they must be designed so that they can be easily shipped to the work site. (Zahner does additional computer work to find the optimal way to load multiple ZEPPS panels onto each truck.)

A close-up look at the underside of a ZEPPS panel and the curved saddle brackets by which it is installed on the steel frame of the Chrysalis. (Click for a higher-resolution version.) Image © 2016 Inner Arbor Trust; used with permission.

Installing ZEPPS panels

In total the Chrysalis features 88 ZEPPS panels containing a total of over 300 profiles. Most of the panels were fabricated at Zahner and shipped to the Chrysalis site, but 16 were fabricated on site: those covering the seven triangles formed by the steel frame and those making up the segments of the nine legs of the Chrysalis from the level of the stage floor down to the ground.

Each ZEPPS panel was pre-positioned on the ground and tilted to the correct angle before being hoisted to its designated position on the steel frame. The orientation of the panels was further adjusted while they were suspended (using a system of chains and pulleys), so that when the workers guided them into place they would match up with the underlying steel frame as closely as possible.

Each of the ZEPPS panels was then attached (using self-tapping galvanized screws) to the primary and (in the case of the seven triangles) secondary steel of the steel frame. Special curved saddle brackets were used to mate the profiles of the panels with the curvature of the steel tubes; this allowed the panels to be attached at any angle with respect to the steel. (See the figure above.)

The panels installed in the Chrysalis also have clear anodized aluminum sheet metal attached to them. (See the figures above and the figure below.) Although this appears superficially similar to the external metal surfaces of other Zahner projects, it instead forms a substrate on which can be attached the true outer surface of the Chrysalis, factory-painted aluminum shingles in various shades of green, as well as an interior surface as discussed below.

Normally the ZEPPS panels themselves are invisible, residing between the underlying opaque building walls and the equally opaque exterior metal surface. In the Chrysalis, on the other hand, the steel tubes of the frame, the aluminum profiles of the ZEPPS panels, and the underside of the anodized aluminum sheet metal covering the panels are visible to anyone looking up, and contribute to the overall visual aesthetic of the structure. Among other things, this led the Inner Arbor Trust and Zahner to choose to use a matte finish on the sheet metal of the panels to provide a clean appearance and avoid glare from theatrical lights.3

Close-up of aluminum shingles of the Chrysalis skin, showing how the shingles were riveted to the sheet aluminum of the underlying ZEPPS panel. (Click for a higher-resolution version.) Note the codes on the upper edge of each shingle specifying its type. See also the figure below. Image © 2016 Inner Arbor Trust; used with permission.

The Chrysalis shingles

In the Experience Music Project Museum and other Zahner projects the metal skin is intended to appear as an unbroken surface to the viewer. The goal therefore is to minimize as much as possible the appearance of any seams between the metal sheets attached to the ZEPPS panels. The Chrysalis skin, on the other hand, is designed to have a highly scaled texture and variegated coloring. Hence it is formed of overlapping shingles, with the boundary between one shingle and the next quite apparent.

In order to securely attach the shingles they were riveted to the underlying aluminum sheets that were part of the ZEPPS panels. (See the figures above and below.) Zahner pre-drilled each shingle in the shop to hold four aluminum rivets, and placed the holes so that the rivets attaching each shingle to the underlying ZEPPS panel would be located only at the upper end of the shingle. The rivets of a given shingle would then be covered by the overlapping lower end of the shingle above it in the structure. The result is that although thousands of rivets (more than 45,000 in all) were used in attaching the shingles, none of them are visible to the eye of the viewer standing on the ground.4

While the shingles break up the surface of the Chrysalis into thousands of pieces (8,200 shingles in all), through their color they also unify the whole of the structure into a single organic form. As noted in a previous article, the shingles are painted in four different colors of green, with the various colored shingles placed on the structure to provide the appearance of a smooth color gradient from a darker green at the bottom to a lighter green at the top (a technique known as "dithering").

Because the shingles will be exposed to the elements and (in the lower sections of the Chrysalis) to human beings, they are painted using Valspar Fluropon, a special architectural coating designed for exterior metal surfaces to provide resistance to UV rays, dirt and stains, and graffiti while retaining its original color and gloss over the years.

The shingles also had to be fabricated in 11 different shapes and sizes to account for the various positions on which they would be installed on the Chrysalis, which combined with the four possible colors made for up to 44 possible varieties of shingles. To assist the installers each shingle was imprinted with an alphanumeric code indicating what type of shingle it is, and thus at what points it could be installed on the structure. (See the figure below.)

The skin of the Chrysalis, including the ZEPPS panels and the shingles, thus forms a giant three-dimensional jigsaw puzzle, with all pieces needing to be precisely designed and fabricated so that they will come together easily without gaps or misalignments and be installable by a relatively small group of people. Unlike a jigsaw puzzle, the skin must also bear loads without failure or any significant deformation, adapt to changing temperatures throughout the four seasons, and retain its structural integrity and visual beauty over the years. Zahner is arguably one of the few contractors, if not the only contractor, that could have accomplished this task within the timeframe and budget allotted to it.

The next article in this series will discuss the structural concrete subfloor of the Chrysalis and related construction on the site.

A map of how shingles were installed over the ZEPPS panels on one part of the Chrysalis. (Click for a higher-resolution version.) The alphanumeric codes indicate the type of shingle to be placed at each location. Compare to the figure above. Image © 2016 A. Zahner Company; used with permission.

For further exploration

This article is based on material from a variety of online sources, including the following:

For more on A. Zahner Company, its work on the Chrysalis project, and related topics, see the following:

"William Zahner markets metal company on complex know-how", by Don Lee, Kansas City Star, February 11, 1992 [paywalled]. An article from soon after Bill Zahner became president of A. Zahner Company.

"Zahner celebrates 100 years proving their mettle in metal", by Randolph Heaster, Kansas City Star, November 25, 1997 [paywalled]. Discusses the past and present of A. Zahner Company on the occasion of its celebrating its centenary.

"Transcript from Interview with L. William Zahner & Crosby Kemper III". A 2015 interview in which Bill Zahner discusses the history and working methods of A. Zahner Company.

"Kansas City, Powerhouse of American Architecture", by Kriston Capps, The Atlantic, November 2015. A profile of A. Zahner Company. See also earlier profiles in Wired and Metropolis.

"Math of Architecture, Architecture of Math" [67-minute video]. An event on November 3, 2015, sponsored by the Inner Arbor Trust to promote the Chrysalis project. Includes a presentation by Bill Zahner starting at 46:44, discussing various Zahner projects, including most notably the Petersen Automotive Museum in Los Angeles.

"Full STEAM Ahead" [62-minute video]. An event on November 3, 2015, sponsored by the Inner Arbor Trust to promote STEM topics associated with the Chrysalis. Includes a brief presentation by Bill Zahner starting at 50:20 discussing the work of A. Zahner Company and the use of architectural metals.

"ZEPPS®". An overview of Zahner's ZEPPS technology, including a link to a 144-page document containing more details and a portfolio of projects.

"A. Zahner Company Customer Story". A video and written case study describing how Zahner used Dassault Systèmes's 3DEXPERIENCE platform (including CATIA) and its Design for Fabrication on Cloud service to fabricate the Chrysalis.

"Design-build". A Wikipedia article providing an overview of the design-build concept.

For more on the Chrysalis amphitheater and its origins in the Inner Arbor concept plan, see the following:

Michael McCall presentation of the Inner Arbor concept plan to Leadership Howard County [33-minute video] (September 20, 2013).

The Chrysalis portion of the Inner Arbor presubmission community presentation (December 2, 2013).

Michael McCall presentation to the Howard County Design Advisory Panel [20-minute video] (February 26, 2014).

For more of my opinions on and explanations of various aspects of the Chrysalis and Merriweather Park at Symphony Woods, see the Inner Arbor-related posts in the series "The Inner Arbor plan takes shape" and elsewhere on this blog. (Note that some of these posts contain outdated information relating to park features that were later dropped or revised.)

Architectural Metals (1995) and Architectural Metal Surfaces (2004). ↩

Zahner's revenue grew from about $5M when Bill Zahner took over to about $45M in 2010, a period during which its number of employees roughly doubled. By 2010 Zahner had also built a new 10,000sf annex to its original factory in Kansas City, and had opened a second facility in Dallas, Texas. ↩

The Inner Arbor Trust, Zahner, and the architects also made several other design changes that individually were relatively small but overall significantly improved the public's viewing experience. For example, the custom ZEPPS panels filling the seven triangles in the steel frame were designed so that one of the profiles within each panel was made longer and oriented in the direction of the pleats in the skin. ↩

The shingles at the top of each "arch" of the Chrysalis are an exception to this, since they overlap the shingles to either side. In this case the shingles are riveted on the side facing away from a viewer on the ground. ↩

Frank firstname.lastname@example.com explain how the skin of the Chrysalis was fabricated and installed by A. Zahner Company.Creating the Chrysalis: Shell structure2017-02-18T08:30:00-05:002017-02-18T08:30:00-05:00https://civilityandtruth.com/2017/02/18/creating-the-chrysalis-shell-structure

Rendering of the steel frame underlying the Chrysalis skin, and the structural concrete subfloor to which the frame is attached. (Click for a higher-resolution version.) Image © 2015 Arup.

tl;dr: I explore the steel frame underlying the skin of the Chrysalis, as designed by the structural engineering group of Arup.

This article is one in a series exploring in depth the creation of the Chrysalis amphitheater in Merriweather Park at Symphony Woods in Columbia, Maryland. For the complete list of articles please see the introduction to the series.

The previous article in this series discussed the demanding structural loads imposed on the Chrysalis by its function as a professional performance stage. In this article I explore the steel frame that underlies the skin of the Chrysalis and enables the Chrysalis to support those and other loads, as designed by Arup and fabricated and erected by the Walters Group and its subsidiary Metropolitan Walters.

The original Sydney Opera House design by Jørn Utzon, from the drawings submitted to the design competition (top), and the final design reflecting advice from Arup on how the building shells might be fabricated (bottom). (Click for a higher-resolution version.) Note the replacement of the original continuous shell roofs with multiple series of concrete ribs. Images from the Sydney Opera House online gallery of the State Archives of New South Wales, Australia, from the competition drawings and the "Yellow Book" respectively.

Arup and structural engineering

The previous article in this series discussed the role of Arup's theater consulting group. However, Arup began life as a consulting firm specializing in structural engineering, the task of which, according to founder Ove Arup, is "to design stable and economical structures of different kinds to meet the requirements for which these structures are needed". In other words, the job of the structural engineer is to translate the vision of the architect into a structure that is fit for the purposes for which it is intended.

After beginning his career working on marine structures (e.g., piers, quays, and breakwaters), Ove Arup became interested in both modern architecture and the then-new technology of reinforced concrete that made new types of structures possible. He set out on his own in 1946, founding Arup and Associates as an independent consulting engineering firm. He and his colleagues soon found themselves working at the cutting edge of architectural practice, as exemplified by the firm's work on the Sydney Opera House.

In the 1950s the government of the state of New South Wales in Australia set out to create a new center for the arts on a prominent site jutting out into Sydney Harbour. The selection committee for the design competition found itself entranced by an entry from Danish architect Jørn Utzon that featured a series of sail-like shells enclosing the two main performance spaces. (See the figure above.) Eager to get the project underway, the government authorized the start of construction, although no one had yet figured out how to build the shells Utzon had envisioned.

As the consulting engineers for the project, Arup the firm found itself at the center of the controversy over how to build what became known as the Sydney Opera House, including most notably how to analyze proposed designs to ensure their safety and stability. Working with Utzon, Arup engineers eventually found a workable solution: converting Utzon's shells into a series of pre-cast concrete ribs of varying sizes, with the ribs arranged in sequence to form a shell-like roof.

To make the structural analysis tractable (especially given the limited computer technology available at the time), the ribs were designed so that both the sides of the arches formed by the ribs (looking at them head on) and the profile when they were connected (looking at them from the side, as in the figure above) were composed of circular arcs.1

Although the Sydney Opera House was dogged by controversies, delays, and cost overruns, the structure was eventually completed and subsequently hailed as one of the world's iconic structures—and, along with the Sydney Harbour Bridge, the symbol of Sydney to the world. It also bolstered the reputation of Arup as a "go to" firm for clients working with world-class architects to get visionary projects built.

That reputation in turn helped Arup in its competition to attract and retain the best engineering talent. As Ove Arup said in his "Key Speech" describing his vision for Arup and principles for its operation, in practice the work of Arup or any other engineering firm can devolve into a series of mundane and potentially boring tasks: "designing endless reinforced concrete floors, taking down tedious letters about the missing bolts, changing some details for the nth time, attending site meetings dealing with trivialities, …—what is exciting about that?"

Thus while the Inner Arbor Trust valued Arup for its proven excellence in working with cutting edge designers to manifest totally unique structures, the Chrysalis was for Arup an opportunity to engage its staff in an interesting and innovative project, even though the scale of the Chrysalis was much smaller than that of the projects that formed the bulk of Arup's portfolio.

One of the eight wind load scenarios analyzed by Arup, one for each compass direction. (Click for a high-resolution animated image showing all of the scenarios.) Warm colors indicate positive pressures on the shell, while cool colors indicate negative pressures (suction). Image © 2015 Arup; used with permission.

Analysing the structure

The responsibility for structural engineering for the Chrysalis fell primarily on those in Arup's Washington DC office, including the young structural engineer Jordan Woodson and his senior mentors at Arup, Matt Larson and Brian Markham. Woodson had wanted to work at Arup ever since he was a freshman in college, and joined the firm soon after completing his graduate degree. In his time with Arup he had worked on projects ranging from the new Mexico City international airport (comprising 8 million square feet, over a thousand times the size of the Chrysalis stage) to the proposed 11th Street Bridge Park project in DC.

The task assigned to Woodson and his colleagues was to determine how the Chrysalis could be built in a manner that would maintain the artistic integrity of Marc Fornes's design, handle the various loads placed upon it (including the skin itself, the natural forces of wind and snowfalls, and theatrical point loads), and fit within the budgetary and other constraints of the project.

This included looking at possible failure scenarios under load—as Woodson remarked, "To understand how something stands up you have to understand how it might fall down". The high asymmetrical arch at the rear of the stage, one of the most visually striking features of the Chrysalis, required particular attention in order to ensure the overall stability of the structure.

Arup considered multiple ideas for instantiating the Chrysalis shell, including riveted aluminum or steel shingles (as in the "Pleated Inflation" structure discussed in a previous article), shingles supplemented by various types of structural reinforcements, and "sandwich panels" of metal sheets placed back to back.

In the end the configuration chosen as best meeting structural, budgetary, and other constraints was a "rib cage" or "skeleton" of steel tubes ("hollow structural section" or HSS pipe) to provide a frame underneath the shell skin, bearing the weight of the skin above and of theatrical loads hanging below. The form of the frame somewhat resembles that of the geometric mesh in the "mesh inflation" process used to create the form of the Chrysalis, with large "primary steel" tubes resembling the "lengthwise" curves of the mesh and smaller "secondary steel" tubes resembling the "crosswise" lines of the mesh.2 (See the first figure above.)

In designing the steel frame Arup performed analyses to determine the effects of various types of load, dividing the primary and secondary steel of the frame into 2-inch straight sections to simplify the computations. Under Arup's direction BMT Fluid Mechanics of London performed extensive wind tunnel testing on a model of the structure, looking at wind forces of up to 60,000 pounds from each of the eight compass directions (north, northeast, east, and so on).

Arup then combined the pressure profiles produced from the wind tunnel testing with 33 different types of theatrical loading of up to 42,000 pounds, arising from the various configurations of the alpha and beta stages discussed in the previous article. In total the final analysis covered 350 different load scenarios.

The results of the load simulations then determined the size of the structural elements in the frame: places in the structure where the loads were greatest called for larger diameter tubes, with smaller diameter tubes used in areas with lesser loads. The final frame includes 1,700 feet of tubes for the frame, with the primary steel being 10 inches in diameter and the smaller crosswise secondary steel 8 inches in diameter.

The primary steel tubes at the bottom of the frame (comprising the "touch down" points of the shell's arches) are attached to concrete piers, which in turn are attached to a structural concrete subfloor. The subfloor acts as a "diaphragm" to provide further rigidity to the overall structure and resist the thrust of the arches. (See the first figure above and the last figure below.) The subfloor supports the stage floor itself (comprised of hardwood panels), while underneath is located a space for storage and electrical equipment.

One of the theatrical load scenarios analyzed by Arup. (Click for a high-resolution animated image showing more scenarios.) The locations of the downward-pointing arrows correspond to the locations of the particular strong points used for each scenario. The length of each arrow indicates the magnitude of the force applied at that point. Image © 2015 Arup; used with permission.

Fabricating and erecting the frame

With Arup having designed the steel frame underlying the Chrysalis shell, the next step was to build it. The Inner Arbor Trust had tasked A. Zahner Company of Kansas City, Missouri, with overall responsiblity for the construction of the portion of the Chrysalis structure above the concrete subfloor. (The next article in this series will discuss Zahner's role in more detail.)

Zahner then turned to the Walters Group of Hamilton, Ontario, a group of companies primarily focused on creating complex structural steel for commercial and industrial construction projects throughout North America, and its subsidiary, New York City-based Metropolitan Walters, specialists in erecting complex steel structures. (Metropolitan Walters and Arup had worked together previously on other projects, including Alice Tully Hall at the Juillard School of Music in New York City.)

As discussed above, as designed by Arup the Chrysalis frame included both long curved elements (the primary steel forming the arches of the Chrysalis and following the line of the pleats in the skin) and shorter straight elements (secondary steel) binding together the curved elements. The primary steel tubes were too long to be fabricated as single pieces, especially given their degree of curvature. Instead they were fabricated as combinations of less-curved shorter tubes, with the tubes then joined on-site to form the final curves of the frame.

Steel structural elements can be either welded together or bolted together. In order to simplify erection of structures and lower costs, the preferred procedure is to minimize the amount of welding to be done on-site. Metropolitan Walters followed this practice for the Chrysalis: the curved elements were fabricated with circular flanges welded in the shop to the 10-inch primary steel tubes and pre-drilled with holes for bolts. Matching elements were then bolted together after they arrived at the construction site.

A similar practice was followed for the secondary steel forming the straight cross pieces: in the shop short sections of 8-inch tubes with circular flanges were welded to the 10-inch primary steel tubes, matching circular flanges were welded to the ends of the straight 8-inch secondary steel tubes used for the cross pieces joining the larger elements, and holes drilled in the flanges. Bolts were again used to connect together the secondary steel and primary steel elements at the construction site.

Those familiar with traditional arches will recall that the two sides of an arch have to be supported during construction. Only after adding the top element of the arch (the "keystone" for stone arches) is the arch stable and able to stand on its own. From this viewpoint the Chrysalis steel frame is "all arches": the entire structure was unstable while being erected until the point where it was (almost) complete. To address this, Metropolitan Walters used 16 temporary towers and supplemental guy wires to hold up partially-erected sections of the frame during construction.

Often when steel structural elements are joined they are designed so that the two elements are able to rotate somewhat relative to each other. In contrast, the bolted connections between the individual tubes of the Chrysalis frame are "moment connections"3 designed to remain rigid and act as a continuous element under load. Since the lowest elements in the frame are connected to the concrete piers and the structural concrete subfloor for the stage, the combined structure (frame plus piers plus subfloor) forms a single rigid structure able to resist loads with a minimum of deflection.

The steel frame underlying the Chrysalis skin and the concrete piers and structural concrete subfloor to which it is attached, prior to the addition of the skin. (Click for a higher-resolution version.) Compare to the figure above, and note the points at which the individual elements of the primary and secondary steel are bolted to each other. Image © 2016 Inner Arbor Trust; used with permission.

Theatrical steel and strong points

The primary and secondary steel tubes form an overall skeleton providing structural integrity for the Chrysalis. However they do not directly support the actual Chrysalis skin, nor (with some exceptions) do they directly bear theatrical loads.

As discussed in the previous article, theatrical loads for Chrysalis productions are to be hung from a set of "strong points" on the structure, each rated to bear a certain amount of load (2,200 pounds of vertically suspended weight for strong points serving the alpha stage). The strong points are designed to form a rectangular grid, but the arrangement of primary and secondary steel tubes is in no way grid-like.

The desired geometry is provided by the separate "theatrical steel", a set of (relatively) thin steel tubes each of which runs from the front of the frame to the rear of the frame. The theatrical steel is bolted to the primary steel, using flanges welded in the shop for this purpose. The strong points themselves are in the form of small steel loops welded to the theatrical steel at regular intervals. (See the figure below.)

As hinted above, there are also a few strong points attached directly to the primary steel, mainly to support speakers to be hung at the sides of the main arch for the alpha stage. (See the strong point diagram linked to in the "For further exploration" section below.)

The combination of primary steel, secondary steel, and theatrical steel making up the frame is capable of supporting up to 58,000 pounds of equipment, assuming use of the alpha stage strong point grid, the attach points for speakers for the alpha stage, and the beta stage strong point grid.

In the steel frame of the Chrysalis Arup has provided an efficient and effective solution to the problem of handling structural loads while retaining the overall aesthetic virtues of the Chrysalis's design. The frame also adds visual interest to the underside of the shell, complementing the dynamic green color of smooth aluminum shingles on the outer skin with the silver-gray industrial aesthetic of galvanized steel tubes and flanged, bolted splices.

The next article will discuss the outer skin of the Chrysalis and how it is attached to and supported by its steel frame.

A view from the Chrysalis stage looking up at a portion of the steel frame. (Click for a higher-resolution version.) The thin straight elements positioned at regular intervals are not part of the steel frame itself; they are part of the ZEPPS units holding up the shingles of the skin. (See the next article in this series.) Image © 2017 Frank Hecker; available under the terms of the Creative Commons Attribution 4.0 International License.

For further exploration

This article is based on material from a variety of online sources, including the following:

For more on Arup, its work in structural engineering in general, and on the Chrysalis project in particular, see the following:

Arup's structural engineering practice

Ove Arup's "Key Speech" outlining Arup's philosophy, mission, and organizational practices

Ove Arup's 90th birthday issue of The Arup Journal. Contains several articles and speeches by Ove Arup, including "What is a Structural Engineer".

"Sydney revisited", by Jack Zunz, in The Arup Journal, 1988, Issue 1. A 1987 lecture by Arup's lead on the Sydney Opera House.

"Engineering is Not a Science", by Patrick Sisson. A 2016 Curbed article that includes a good summary of Ove Arup's life and work.

"How Arup Became The Go-To Firm for Architecture's Most Ambitious Projects", by Ian Volner. A 2013 ArchDaily article that discusses Arup's more recent projects.

"Full STEAM Ahead" [62-minute video]. An event on November 3, 2015, sponsored by the Inner Arbor Trust to promote STEM topics associated with the Chrysalis. Includes a presentation by Jordan Woodson of Arup starting at 29:40 discussing structural analysis of the Chrysalis.

"Chrysalis Theatre Loading Plan". A diagram showing the location of strong points and instructions for their use.

For more on the Walters Group, Metropolitan Walters, their role in fabricating and erecting the steel frame of the Chrysalis, and structural steel in general, see the following:

"Walters Group". Corporate "about" page.

"Metropolitan Walters selected as partner in Columbia Maryland's Chrysalis project". Press release.

"Tubular Transformation". A 2016 article in Modern Steel Construction describing the steel frame of the Chrysalis.

"Erecting the Chrysalis steel" [8-minute video]. Offers a glimpse at the process of erecting the Chrysalis steel frame.

"Structural Steel Connections", by the American Institute of Steel Construction (AISC). A presentation discussing the various ways to connect structural steel members. Slides 16 and 17 address moment connections.

For more on the Chrysalis amphitheater and its origins in the Inner Arbor concept plan, see the following:

Michael McCall presentation of the Inner Arbor concept plan to Leadership Howard County [33-minute video] (September 20, 2013).

The Chrysalis portion of the Inner Arbor pre-submission community presentation (December 2, 2013).

Michael McCall presentation to the Howard County Design Advisory Panel [20-minute video] (February 26, 2014).

For more of my opinions on and explanations of various aspects of the Chrysalis and Merriweather Park at Symphony Woods, see the Inner Arbor-related posts in the series "The Inner Arbor plan takes shape" and elsewhere on this blog. (Note that some of these posts contain outdated information relating to park features that were later dropped or revised.)

The analysis for the Sydney Opera House was done in the early 1960s. Recall from the earlier article on the design of the Chrysalis that this was before the invention of NURBS curves and surfaces and of techniques to analyze such surfaces under load. ↩

One major difference is that the original mesh was composed only of quadrilaterals, while the steel frame uses triangles at key points to provide increased rigidity for the structure. ↩

In this context "moment" is another word for force. A moment connection is named thus because it transmits forces unmodified across the connection point, with minimal deflection of the structure at that point due to so-called "bending moments" that act to rotate one element relative to the other. ↩

Frank firstname.lastname@example.com explore the steel frame underlying the skin of the Chrysalis, as designed by the structural engineering group of Arup.Creating the Chrysalis: Theater2017-01-21T18:00:00-05:002017-01-21T18:00:00-05:00https://civilityandtruth.com/2017/01/21/creating-the-chrysalis-theater

Rendering of the Chrysalis alpha stage in use, including suspended speakers and lighting equipment. (Click for a higher-resolution version.) The beta stage is to the right (stage left). Image © 2015 Marc Fornes; used with permission.

tl;dr: I discuss how the Chrysalis will function as a professional stage, as designed by the theater consulting group of Arup.

This article is one in a series exploring in depth the creation of the Chrysalis amphitheater in Merriweather Park at Symphony Woods in Columbia, Maryland. For the complete list of articles please see the introduction to the series.

The previous article in this series focused on the overall architectural form of the Chrysalis amphitheater, designed to function as a stage, pavilion, and sculpture for Merriweather Park at Symphony Woods. In this article I discuss in more detail those aspects of the Chrysalis relating to its function as a professional performance stage.

Snape Maltings Concert Hall, built in 1966-1967 as part of the repurposing of a old malt house in the village of Snape, in Suffolk, England. (Click for a higher-resolution version.) This was one of Arup's first major projects in theater design and acoustic consulting. Image © 2016 Arup; from the Arup Journal 50th Anniversary Issue.

Arup and theaters

Arup Group Limited, usually known simply as "Arup", is a large consulting firm with more than 13,000 employees and offices in almost 100 locations around the world, including New York and Washington DC. Originally founded in 1946 by the British engineer Ove Arup, Arup the firm is known in particular for its collaboration with leading architects to create innovative and iconic structures, including (among others) the Sydney Opera House, the Centre Pompidou in Paris, the Øresund Bridge between Denmark and Sweden, the Lloyd's of London headquarters and 30 St Mary Axe ("The Gherkin") in London, the National Stadium ("Bird's Nest") and National Aquatics Center ("Water Cube") built for the 2008 Summer Olympic Games in Beijing, and the China Central Television (CCTV) headquarters, also in Beijing.

For the most part eschewing the role of project architect, Arup instead concentrates on all the other design and engineering consulting work needed to translate architects' visions into reality. In particular this includes practices in theater consulting, acoustic consulting, structural engineering, and lighting design, with Arup having worked on several dozen projects worldwide involving concert halls, indoor and outdoor theaters, and similar structures.

Given Arup's broad range of expertise and their reputation for working with leading architects, Arup was a natural choice for the Inner Arbor Trust to include on the design team for Merriweather Park at Symphony Woods and for the Chrysalis in particular. Raj Patel of Arup's New York office–Arup principal1, global lead for theater and acoustic consulting, and arts, culture, and entertainment business leader for the Americas—was introduced by the Trust at the "Designers of Delight" presentation in November 2013. Patel discussed several Arup theater projects, from the Snape Maltings Concert Hall (see the figure above) to the recent Jerome Robbins Theater in the Baryshnikov Arts Center in New York City.

Examples of two possible audiences for a Chrysalis performance: 2,000 people seated on the lawn for a performance on the alpha stage (L), or 1,000 people seated on the lawn for a performance on the beta stage (R). (Click for a higher-resolution version.) Images © 2014 Arup; included in the Inner Arbor Trust presentation to the Howard County Design Advisory Panel.

Alpha and beta

The purposes that the Chrysalis is to fulfill influenced its overall design. As noted previously, Michael McCall of the Inner Arbor Trust described the Chrysalis as a combined stage, pavilion, and sculpture. Setting aside the functions of pavilion and sculpture, the simple word "stage" contains a host of questions regarding what types of performances the Chrysalis might host, how the sights and sounds of those performances are to be conveyed to the audiences, how many and what kinds of people are part of the audiences, how those people experience the performances, and so on.

For an example of how the answers to these questions influence the form of a performance space, look no further than Merriweather Post Pavilion, neighbor to the Chrysalis. When it was originally constructed Merriweather Post Pavilion was conceived of as a summer home for the National Symphony and a venue for other "high culture" performances, including dance. Thus the audience area was relatively small and featured conventional seats, and the venue and stage were designed for acoustical performances. However, after the National Symphony went bankrupt Merriweather Post Pavilion eventually evolved into a venue for popular acts featuring amplified music, with the seating area expanded and additional audience seating space used on the lawn above the pavilion.

Some of the decisions about the Chrysalis were made early on, as part of the development of the Inner Arbor concept plan and prior to the design of the Chrysalis itself. In particular, the concept plan included provision for both indoor theaters and an outdoor stage, the so-called Treehouse amphitheater, in a proposed "performance park" area of Symphony Woods. The role of the indoor theaters was eventually taken over by the cultural arts center now being proposed for a site across the street from Merriweather Park to house Toby's Dinner Theatre and other functions, leaving the outdoor amphitheater to be addressed by the revised Inner Arbor plan.

Since the amphitheater was to be located in a more forest-like section of Symphony Woods, and since an explicit goal of the Inner Arbor plan is to preserve as many trees as possible, the Inner Arbor Trust opted not to install fixed seats or benches in Symphony Woods itself. Instead audiences will sit on the lawn or (for larger events) stand.

Also, since the amphitheater was only a few hundred feet from South Entrance Road and the proposed route of a future larger street, the ambient noise level dictated the use of amplification for performances. This in turn opened up more possibilities for the amphitheater structure itself, which did not need to take the traditional form of an acoustic shell. The result was the unconventional form of the Chrysalis as we know it today.

The combination of lawn seating and sound amplification matched up well with the planned uses of the Chrysalis as a secondary stage for Merriweather Post Pavilion (for example during music festivals) or as a primary stage for events like Wine in the Woods. The hill facing the Chrysalis, which serendipitously has a gently sloping natural 5% grade, can easily accommodate audiences of up to 2,000 people if seated (see the figure above) and many more than that if standing.

At the same time there are other possible events that generally play to smaller audiences—local groups and solo performers, small plays, and the like—and will not need that much stage space. Rather than force these performances to use a large stage, the Chrysalis was designed to have a second or "beta" stage facing a different part of the hill, one that can accommodate audiences from 100 to 1,000 people if seated, and more if standing. Unlike the main or "alpha" stage, the beta stage also has terraced steps forming a thrust stage to provide a more informal and intimate relationship between the performers and the audience.

Examples of two possible setups of the Chrysalis alpha stage, for a pop group (L) and for a lecture to an on-stage audience (R). (Click for a higher-resolution version.) Images © 2014 Arup; included in the Inner Arbor Trust presentation to the Howard County Design Advisory Panel.

Configuring the stages

However, even the addition of the beta stage did not address the full range of demands that are likely to be placed on the Chrysalis. Some performances and other events will be so small scale that they may need to accommodate an audience of only a few dozen to a couple of hundred people. For many such events, such as book readings or lectures, it may also be preferable to provide formal seating arrangements for the audience, as opposed to having them sit or stand on the lawn.

To address these requirements the Chrysalis is designed so that the stage can also be used as a seating area for the audience in addition to a performance space, with the whole event then taking place under the canopy of the Chrysalis. This also provides the audience at least partial protection from any inclement weather.

The resulting Chrysalis stage as designed and constructed is quite large: about 4,500 square feet for the main stage floor, with a "performance zone" for the alpha stage about 50 feet wide and 40 feet deep—roughly comparable to the stage at Carnegie Hall and to the old Merriweather Post Pavilion stage prior to the construction of the new stagehouse. There are also additional areas "in the wings" at stage left and stage right of the alpha stage, as well as an area of over 500 square feet for the terraced levels of the beta stage that project outside the Chrysalis proper.

The resulting venue can accommodate a wide variety of events and associated stage configurations:

Popular music acts on the alpha stage, including rock or hip hop performance (see the figure above) or DJs playing electronic dance music (EDM), with the audience seated or standing on the lawn.

Theater, dance, orchestral, and chorus performances on the alpha stage, with the stage being large enough to support a symphony orchestra with close to 100 performers and a backing chorus of comparable size.

Smaller performances with the audience seated on the alpha stage itself, with 100-150 people seated in one or two banks of seats and the performers either at center stage or at stage right (near the beta stage).

Larger events with 300-400 or more people seated on the stage, for example for a lecture or book reading (see the figure above).

Performances on the beta stage with audiences seated or standing on the lawn.

In practice each event will be slightly different, with the size and shape of the Chrysalis stage providing the flexibility for creative presenters and event organizers to select the configuration that best helps them achieve their particular artistic and business goals.

Chrysalis theater features, clockwise from upper right: technical specifications, including load capacities for lighting and speakers; the grid of "strong points" for hanging lights and speakers for performances on the alpha and beta stages; location and capacities of electrical switches; and storage space under the alpha stage. (Click for a higher-resolution version.) Image © 2016 Inner Arbor Trust; used with permission.

Expected technology, unexpected form

Of the possible configurations and their requirements, the most demanding are those needed to accommodate popular music acts like those that form the majority of the performances at Merriweather Post Pavilion and its associated music festivals.

One aspect of the public image of major rock stars is that they make whimsical and often nonsensical demands of the venues in which they perform. Of these the most famous is the "no brown M&Ms" rule associated with the rock band Van Halen: that they be served a bowl of M&M candies in their backstage dressing rooms, with all brown M&Ms removed.

On the surface this portrays the members of Van Halen as divas of the highest order, but in reality the purpose of this contract clause was much more prosaic: Van Halen's stage show used a lot more equipment than many of the venues they played at were used to, and they wanted to ensure that the venue staff were fully aware of Van Halen's technical needs and prepared to meet them. The "no brown M&Ms" provision thus served as a test of whether the venue staff had actually read Van Halen's contract in full, including the associated "hospitality rider" and "technical rider". As Van Halen's leader singer David Lee Roth put it, "If I saw a brown M&M in that bowl … [we'd] line-check the entire production."

Thus when designing the stage the Chrysalis team looked at technical riders for acts that might play at Merriweather Post Pavilion and had particularly stringent requirements. One result was the choice of stage size mentioned earlier. Another was the height of the Chrysalis, designed to provide a 60 feet wide and 36 feet tall proscenium opening at the front of the alpha stage, and a performance "box" 30 feet in height (and 50 feet wide by 40 feet deep) even before allowing for rigging above the stage.

Yet another was the electrical facilities for the two stages. (The term "electrical outlets" doesn't do justice to the size and complexity of the setup.) The Chrysalis features four "company switches" at stage level each capable of providing 400 amps, or 1,600 amps in total, with two other switches each providing 200 amps on isolated circuits for audio equipment, and yet another switch to drive motorized chains for the stage rigging. The total capacity of over 2,000 amps is roughly equivalent to that provided for the new stage at Merriweather Post Pavilion, designed to serve the needs of the most power-hungry acts. (In comparison, a typical medium-size home has 100 amps of electrical service.)

The Chrysalis and its stage are designed to address many other issues, including providing a sturdy stage floor that can also be easily repaired as needed, drainage for the stage, fire suppression, ADA access to the stage for people using wheelchairs or otherwise having limited mobility, sturdy but attractive railings to prevent falls, a loading dock and lift to bring equipment from the dock to stage level, storage under the stage for unused equipment, and so on.

The most important requirement, and a major influence on the final form of the Chrysalis, is to support elaborate rigs for lighting, speakers, suspended scenery, and related elements. The Chrysalis structure supports several dozen "strong points" and multiple "line sets" for hanging production elements.2 Each strong point on the alpha stage is rated to support up to 2,200 pounds of vertically suspended weight, almost as much as a typical subcompact car. (Beta stage strong points are rated to support 1,000 pounds.) The entire set of strong points and line sets, including strong points at the front of the alpha stage for speakers, can support up to 46,000 pounds, equivalent to ten SUVs.

The end result is a professional theater and stage that provides "expected technology in an unexpected form", as Ed Arenius, Associate Principal of Arup, put it: all the features needed for modern musical acts and other performances in a flexible and beautiful structure that is a far cry from the typical outdoor amphitheater.

For further exploration

This article is based on material from a variety of online sources, including the following:

For more on Arup and its work in theater design and consulting, see the following:

"About Us" page from the Arup web site.

Ove Arup's "Key Speech" outlining Arup's philosophy, mission, and organization practices.

Arup's theater consulting and acoustic consulting practices.

"Unabashed Designers of Delight" [121-minute video] (November 18, 2013). A presentation introducing the design team for the Inner Arbor plan. It includes a presentation by Raj Patel beginning at 1:39:30 that discusses a number of Arup theatrical projects.

For more on technical requirements for acts playing concert venues, and theatrical requirements in general, see the following:

"Brown Out". Snopes.com investigates Van Halen's "no brown M&Ms" demand.

"Merriweather Post Pavilion Production Information". Includes detailed technical specifications of the stage and other features for acts playing at Merriweather Post Pavilion.

"How to Make the Perfect Tech Rider for Your Band". A good example of what goes into a typical technical rider, although it doesn't make much mention of lighting requirements.

"Fly system". A Wikipedia article that provides a good overview of the components and complexity of the equipment needed for a modern stage production.

"Stagecraft Industries Site Glossary". A glossary of technical terms used in the context of theaters and theatrical productions.

For more on the Chrysalis amphitheater and its origins in the Inner Arbor concept plan, see the following:

Michael McCall's presentation of the Inner Arbor concept plan to Leadership Howard County [33-minute video] (September 20, 2013).

The Chrysalis portion of the Inner Arbor pre-submission community presentation (December 2, 2013).

Michael McCall's presentation to the Howard County Design Advisory Panel [20-minute video] (February 26, 2014).

For more of my opinions on and explanations of various aspects of the Chrysalis and Merriweather Park at Symphony Woods, see the Inner Arbor-related posts in the series "The Inner Arbor plan takes shape" and elsewhere on this blog. (Note that some of these posts contain outdated information relating to park features that were later dropped or revised.)

Arup began as a traditional partnership but then later transitioned to being owned by a trust on behalf of its employees. A principal at Arup is roughly equivalent to a partner at other firms. Arup has a global board of directors (appointed by the trustees) and then individual boards for each of its major regions. Raj Patel is a board member for the Americas region. ↩

A strong point is an individual point to which a load can be attached. A line set consists of multiple components, including a horizontal pipe ("batten") and a set of ropes and pulleys used to raise and lower it. A strong point is typically not used in isolation; instead a group of strong points is used to support a single line set, which then is used to support lights, a curtain, piece of scenery, or other element used in a production. ↩

Frank firstname.lastname@example.com discuss how the Chrysalis will function as a professional stage, as designed by the theater consulting group of Arup.Creating the Chrysalis: Design2017-01-07T06:00:00-05:002017-01-07T06:00:00-05:00https://civilityandtruth.com/2017/01/07/creating-the-chrysalis-design

Snapshot of the "mesh inflation" process for the Chrysalis amphitheater shell. (Click to see the original video.) The original surface prior to inflation is outlined in yellow, with the lines of the mesh running "lengthwise" and "crosswise" shown in purple and blue respectively. Image © 2014 Marc Fornes; used with permission.

tl;dr: I explore the design of the Chrysalis amphitheater, the work of its designer Marc Fornes of THEVERYMANY, and the concepts underlying the design.

This article is one in a series exploring in depth the creation of the Chrysalis amphitheater in Merriweather Park at Symphony Woods in Columbia, Maryland. For the complete list of articles please see the introduction to the series.

The previous articles in this series focused on the history of Symphony Woods, the site of the Chrysalis amphitheater, and the overall design of Merriweather Park at Symphony Woods. With this article I finally turn to the Chrysalis amphitheater itself, the structure after which this series is named. In particular I discuss the concepts and techniques underlying the innovative way in which the form of the Chrysalis was designed, and explore the work of its designer, Marc Fornes of THEVERYMANY, in the years leading up to the creation of the Chrysalis. (Later articles will cover other aspects of the Chrysalis design and other members of the design team, including the work of Arup Group Limited and A. Zahner Company.)

This post is more technical than others in this series, because it's difficult to get a sense for the significance of what Marc Fornes and his associates have achieved without delving a bit into the mathematics and programming techniques that make those achievements possible. I encourage you to check out the videos and interactive demos to which I link, and to lightly skim over sections if the going gets rough.

Apache wickiup in the Southwest US, photographed by Edward Curtis in 1903. (Click for a higher-resolution version.) Image from the Wikipedia article "Wigwam"; in the public domain.

Nonlinear beginnings

Marc Fornes is an architect using advanced computer techniques to create structures based on complex nonlinear forms. In a way his work, and that of others like him, represents a coming-together of two ancient ways of building.

The first, dating back to our hunter-gatherer ancestors and continued with nomadic and small-scale agricultural societies, is the long tradition of "folk architecture" built along natural and organic lines, including most notably tents and tent-like structures in their various forms: wigwams, wikiups, tipis, yurts, and so on. These structures were (and are) typically small scale (built as family residences), based on natural forms and materials (wood bent to shape, cloth under tension), constructed by small teams working quickly, and often explicitly intended as temporary (since a group might spend only a relatively short time in one place).

As such these structures were not "architected" in the sense of being based on detailed specifications created by an architect for use by those who build the structures—there was no real need to do so, since the "architect" and "builder" were one and the same (and often were the user of the structure as well). In any case the nonlinear form of the structures made it difficult to describe them using conventional architectural plans as we think of them today. Instead such structures were constructed using methods worked out by trial and error over many years and taught by one generation of builders to the next.

We can think of these methods, each producing a specific type of structure, as being algorithms—not algorithms that were written down but algorithms that were transmitted verbally and then executed by the builders to create each structure. The algorithms were not arbitrary, but were constrained by the type of material used and the general type of structure to be produced. The final form of the structure was then determined by the algorithm, the materials, and the interplay of forces of compression and tension acting on those materials as they happened to be arranged.

Leveraging the natural forms and properties of the underlying materials also produced structures that were optimized in terms of their use of materials, neither using too much material (and thus wasteful of effort) or too little material (and thus failing to fulfill their intended functions as shelter, etc.). The structures' materials naturally assumed an organic form determined by the forces acting on them, and if additional forces (e.g., due to wind and weather) caused a structure to fail in certain places then builders learned how and where to use additional materials to reinforce the structure.

Reconstructed facade of the Neo-Sumerian Great Ziggurat of Ur, near Nasiriyah, Iraq. (Click for a higher-resolution version.) Image from the Wikipedia article "Ziggurat"; in the public domain.

Building blocks and linear thinking

Although hunter-gatherers, nomads, and small-scale farmers can be thought of as being informal architects, the way of building we most think of as "architectural" in character dates back several thousand years to the beginnings of large-scale hierarchical societies, when bricks and cut stone blocks began to be used in the construction of structures both small and large.

In particular bricks and blocks were ideal for constructing large-scale structures, since builders could leverage techniques of mass production: have a large work force create bricks or cut blocks in parallel, and then have a second work force assemble the bricks or blocks into finished structures.

However this meant that "master builders" needed some method by which workers could be instructed to lay the bricks or blocks in accordance with the builders' mind's-eye vision for the structure. This was especially important for large structures that might take multiple decades to build, long enough that the original master builders might be gone from the scene by the time the structures were completed.

In response to this need builders created the concepts students learn today in geometry class—straight lines, right angles, rectangles and triangles, and so on—to represent various architectural forms, along with simple but powerful tools to help workers embody those forms in physical structures—for example, plumb bobs to create vertical lines, or wooden triangles with sides in the proportion of 3 to 4 to 5 to create right angles.

These basic techniques to create various linear forms, along with additional techniques to allow construction of circular segments for arches and domes, served builders well for many centuries and became deeply embedded in the architectural and contruction practices of agricultural and (later) industrial societies. (The tale of the three little pigs and their respective houses captures this dynamic, promoting the superiority of linear forms constructed using solid materials over folk architecture using straw or sticks.)

Traditional wooden spline held in place by lead ducks. Image from "Interpolação Spline" by Tereza Godim; original source unknown.

Ducks, splines, and lofts

The use of arbitrary nonlinear forms in architecture was thus, for the most part, abandoned as societies became more complex and constructed larger and more elaborate structures. One major exception was in shipbuilding. Kingdoms, empires, and nation states creating large navies needed to construct large numbers of relatively identical ships, each of which required a relatively large construction force.

However the hulls of ships must be composed of streamlined curved forms that cannot be described in terms of linear or even circular segments, so naval architects needed to find other ways to define hull shapes in ways that could be reliably translated by ship builders to create the actual vessels.

One time-honored way in which this is done is to use flexible wooden strips ("splines") in combination with multiple lead weights ("ducks"). The ducks are attached to a spline and force it to flex into a particular shape; the ducks are then moved around until an appropriate smooth curve is produced. The resulting curves are then followed in producing plans for the ship's hull. Since the plans are full size (i.e., using a 1-1 scale) they need to be constructed in a large open space or loft, hence the name "lofting" for the overall process.

Citroën DS on the streets of Nancy, France. (Click for a higher-resolution version.) Image © 2013 Alexandre Prévot; used under the terms of the Creative Commons Attribution-ShareAlike 2.0 Generic license.

Mathematics to the rescue

Manual lofting continued to be used for ships well into the 20th century, and was later adapted for use in designing and constructing other streamlined forms, including airplanes and automobiles. However the process was very labor intensive and difficult to get right, so as electronic computers came into more widespread use after World War II automakers and aircraft manufacturers sought to enlist them in the design process, especially in conjunction with computer-driven machine tools that could take numeric instructions and create finished parts or molds.

At the same time traditional architecture was beginning to liberate itself from the constraints of linear forms, as the use of steel, reinforced concrete, and other new materials made it possible, at least in theory, to produce new types of structures that went beyond rectilinear and circular forms. But, as in designing ships, airplaces, and automobiles, it was easier to imagine new nonlinear forms than to describe them in detail sufficient to guide their construction—not to mention the problem of analyzing such structures to determine whether they would be structurally sound.

Using computers to create forms with complex curves and surfaces required finding compact mathematical ways to represent complex curves, programming computers to accurately and efficiently draw such curves, and (last but not least) making these techniques usable by people who didn't have specialist mathematical or programming knowledge.

This was the challenge faced by Paul de Faget de Casteljau in 1959 when, fresh from earning a PhD in mathematics, he joined the French automaker Citroën. The recently-introduced Citroën DS model was acclaimed for the elegance of its curved unibody design, a form that was produced in a traditional way using clay and wood models. The models' dimensions were then transferred to paper blueprints used in producing the body panels and related parts. All of these steps required painstaking manual work.

De Casteljau's assigned task was to find a simpler way to represent the curves of an automobile's body and parts, one that would be easier to use with the computer-controlled machine tools then coming into use at Citroën and elsewhere—a task made particularly urgent because while de Casteljau was working on the problem the wood modelers at Citroën went out on strike.

An example of a cubic Bézier curve calculated using de Casteljau's algorithm, with control points A, L, I, and P as shown. A point D on the curve can be produced as follows: given a value between 0 and 1, find the points B, M, and J that are located at that fraction of the total length on the line segments AL, LI, and IP respectively. Then find the points C and N that are located at that fraction of the length on the line segments BM and MJ respectively. Finally, find the point D located at that fraction of the length on the line segment CN. Image © 1963 Automobiles Citroën, from the technical report "Courbes et surfaces à pôles" by Paul de Casteljau (as excerpted in "A History of Curves and Surfaces in CAGD", by Gerald Farin).

From points to curves

De Casteljau found a way to represent curves using a fixed set of mathematical expressions (known as Bernstein polynomials1) in combination with a set of variable control points (see the figure above), each having horizontal (x) and vertical (y) values jointly specifying its position.

For example, if four control points are to be used then we start with the standard set of four Bernstein polynomials. The four control points can then be placed anywhere on the flat surface on which the curve is to be drawn (i.e., they can have arbitrary x and y values); each control point is associated in turn with one of the four Bernstein polynomials being used.

The problem of drawing a curve is then reduced to the following procedure, which can be thought of as occurring over an interval of time running from zero to one (e.g., from zero to one minute):

Start at the initial value of time (t = 0), evaluate the given mathematical expressions (the Bernstein polynomials) for that time value, and use the resulting values in conjunction with the control points' x and y values to derive the position for the first point on the curve.2

Advance the time by a small increment, recompute the Bernstein polynomials for that new time value t, and again use the resulting values in conjunction with the control points to derive the position for the next point on the curve.

Repeat step 2 until you arrive at the final value of time (t = 1), at which point the final point on the curve is derived and the curve is complete.

The number of control points used determines the type of mathematical expressions used and the type of curves that can be drawn: using two points produces a line segment, using three points produces a segment of a parabola (the type of curve produced by a ball thrown into the air), using four points produces a cubic curve (so-called because the underlying parameter is multiplied by itself and then multiplied by itself again, as is done in computing the volume of a cube), and so on.

Because of the way the Bernstein polynomials are defined and associated with the control points, the curve produced is guaranteed to start at the first control point, to end at the last control point, and to pass (relatively) close to each intermediate control point. Changing the shape of the curve, or its starting and ending points, can be done by moving the positions of the control points (analogous to moving the ducks attached to a traditional spline). More complicated curves can be created by using more control points (analogous to adding more ducks) and correspondingly more complicated mathematical expressions (Bernstein polynomials of higher degree).

Note that this is not the only way to draw such curves. In particular, de Casteljau invented an elegant way to find points on a given curve using a geometric process involving lines between the control points. (See the figure above for a more in-depth explanation.) What is now known as the de Casteljau algorithm is mathematically equivalent to computing curve points using the Bernstein polynomials.

De Casteljau's work saw immediate application at Citroën in the early 1960s, and was considered so important that Citroën treated its mathematical foundations as a trade secret for many years. However in the meantime engineers at rival French automaker Renault heard rumors about what was happening at Citroën and set out to implement a similar system.

Renault engineer Pierre Bézier independently discovered a representation for complex curves later shown to be mathematically equivalent to that of de Casteljau. Bézier's associate Daniel Vernet independently invented de Casteljau's geometric algorithm. Bézier, Vernet, and others at Renault then used these techniques to develop UNISURF, one of the first widely-used computer programs for what came to be known as computer aided design or CAD.

Unlike Citroën, Renault took a more relaxed attitude towards publicizing the technical achievements of its employees, and allowed Bézier and Vernet to publish various papers about their work in the late 1960s and early 1970s. Bézier also promoted Renault's accomplishments in personal visits to other CAD researchers in academia and industry. As a result curves created using Bernstein polynomials are now universally known as Bézier curves.3

An example of a NURBS curve of order 3 (degree 2), with seven control points (in green, with values at the upper left) and ten knot values (at the lower left). (Click for a higher-resolution version.) Point3 and Point5 have twice the weight of the other points (see the w values in the list of control points), so that the curve passes more closely to them. Also, the value 0.5 is repeated twice in the list of knots, so that the curve has a kink at Point4. The curve is thus a true example of a non-uniform rational b-spline: non-uniform because the knots are not all evenly spaced, and rational because the control points' weights are not all one. Screenshot taken from the NURBS-Calculator interactive demo, © 2016 firstname.lastname@example.com.

Beyond Bézier

The invention of Bézier curves and their application in engineering marked the beginning of the discipline of CAD (also known as computer aided geometric design or CAGD), and the 1960s and 1970s saw a steady flow of improvements and refinements of the work done at Citroën, Renault, and elsewhere.

Designing real-world artifacts required ways to generate surfaces (not just curves), as well as ways to generate more complicated curves than could be represented using simple Beziér curves. Let us first focus on the issue of generating more complex curves, and look at two ways to create such curves using Bézier curves.

The first approach is simply to use more control points (corresponding to higher-degree Bernstein polynomials). The problem with this approach is that in a Bézier curve each of the control points has at least some influence over essentially all of the curve. This makes it difficult to tweak a Bézier curve to match a pre-defined idea of what the curve should look like: if you move one of the control points in an effort to make a change in one portion of the curve, that movement will end up affecting other portions of the curve that you don't want to change.

A second way to create a more complex curve is to build it out of multiple Bézier curves joined end to end. The problem with this approach is that it is difficult to get the resulting composite curve to smoothly transition from one of the underlying Bézier curves to the next, as is required in applications like auto body design.4

Greater smoothness can be obtained by constraining the control points of one of the underlying Bézier curves relative to the control points of the previous or next curve, but for reasons mentioned above this can lead to difficulties when trying to tweak the shape of the overall curve in certain places.

The solution to this problem was to replace Bernstein polynomials with more general functions known as basis splines. In mathematics "splines" are functions pieced together out of multiple polynomial expressions, with each expression being non-zero only on a particular interval. They are named by analogy to traditional wooden splines, since the expressions and their associated intervals are chosen such that the curve produced by the function flows smoothly from one interval to the next.

"Basis splines" or B-splines form a special set of spline functions that can be combined to represent any spline function created using polynomial expressions of the same level of complexity, or order.5

A fixed set of B-spline functions is then combined with a set of variable control points to draw a curve, similar to what was described above for Bernstein polynomials and Bézier curves. The underlying parameter used in the B-spline functions goes from some minimum value to some maximum value. Unlike Bézier curves the minimum value may be different than zero, and the maximum value different than one.

A set of numbers known as knots then defines a set of intervals for the parameter between its minimum and maximum values. If the knots are chosen appropriately then a particular B-spline function will have non-zero values only on a few adjacent intervals, and will be zero on all other intervals.

When the B-spline function associated with a given control point has non-zero values only on certain intervals of the underlying parameter, moving that control point affects only the parts of the curve drawn over those intervals. This addresses the first deficiency of Bézier curves discussed above.

The second concern (smoothness of the curve between the intervals) is addressed by the mathematical definition of the B-spline functions: their shape is such that their influence (and thus the influence of their associated control points) tails off smoothly at the beginning and/or end of the intervals for which they are non-zero.

By varying the knot values the curve can be constrained and shaped in various ways. For example, setting multiple knot values to be the same at the beginning of the knot series can be used to constrain the curve to start at the first control point, while setting multiple knot values to be the same at the end of the knot series can be used to constrain the curve to end at the last control point. The curve also varies depending on whether the knot values are evenly spaced (uniform) or otherwise (non-uniform). For example, setting multiple knot values equal to each other in the middle of the knot series can be used to produce kinks in the resulting curve.

Finally, the control points themselves can be given differing weights when combined with their B-spline functions. A control point with a higher weight will have a greater influence on the curve, so that the curve will pass closer to the control point in question. Another control point may have a lower weight and thus only a fraction of the influence of other control points, so that the curve passes relatively further away from the point. Another word for fraction is ratio, and thus B-splines with differing control point weights are known as rational B-splines.

In the most general case the knot values are non-uniform, and the control points have different weights. The resulting curve is referred to as a non-uniform rational B-spline curve, or a NURBS curve for short.

A NURBS surface showing the grid of control points (L) and how the underlying parameters u and v are varied from their minimum to their maximum values in computing points on the surface (R). (Click for a higher-resolution version.) Image © 2017 Autodesk, from The Dynamo Primer; used under the terms of the Apache open source license.

From curves to surfaces

The mathematical formalisms underlying practical applications of NURBS curves were worked out in the 1960s and 1970s. Among other things, it was discovered that Bézier curves are just a special case of NURBS curves. It also turned out that NURBS curves could be used to represent conic sections, that is, curves like circles and ellipses formed by slicing a plane through a cone. NURBS curves thus became a universal standard for representing 2-dimensional curves of almost any type.

What about 3-dimensional curves and surfaces? Extending NURBS curves into three dimensions is very simple: just use control points with three coordinates instead of two (in mathematical terms, adding a z value to the previous x and y values). Creating 3D surfaces from NURBS curves is somewhat more complicated.

One way to do it is to use a grid of (3-dimensional) control points (and associated weights), two different parameters (instead of the one parameter used for a NURBS curve), two sets of B-spline functions (which can be of different orders), and two sets of knots.

One set of B-spline functions and knots is used with the first parameter (u) and the x-y-z coordinates of the control points running in one direction on the grid, with the second set of B-spline functions and knots then used with the second parameter (v) and the coordinates of the control points running in the other direction on the grid. A point on the surface is then computed for a given pair of parameter values u and v, using an expression that involves both sets of B-spline functions and both sets of knots along with the control point coordinates.

An example of using the Rhino modeling software to create a NURBS surface from four edges, each of which is a NURBS curve of order 4 with seven control points (shown) and nine knots. (Strictly speaking there should be eleven knots, but Rhino uses an optimization technique that eliminates two superfluous knots.) (Click for a higher-resolution version.) The geometry was created by less than 50 lines of code in the Python programming language. Rhino 5 for Mac software © 2016 Robert McNeel & Associates. Python script © 2016 Frank Hecker; published under the terms of the MIT open source license.

Computer aided design

In practice designers creating NURBS curves and surfaces are not concerned with the detailed mathematical computations underlying these objects. Instead they create curves and surfaces using special CAD software products that abstract away as much of the underlying mathematical complexity as possible, and provide relatively intuitive interfaces to define the curves and surfaces.

For example, using CAD software a designer can create a NURBS curve by explicitly placing control points and defining knot values and weights, or they can draw a curve freehand and then have the software determine the control points, knots, and weights needed to approximate the freehand curve. In either case a designer can further tweak a curve as needed, for example by dragging control points to new positions, deleting existing control points or adding new ones, changing knots and weights, and so on.

Once NURBS curves are defined they can then be used to create NURBS surfaces. For example, if four NURBS curves are connected together to form a four-sided shape, the software can use the four edges to interpolate a four-sided NURBS surface between. (See the figure above.) Multiple such surfaces can then be patched together to form a larger surface.

The earliest major CAD programs were developed internally at major automotive and aerospace companies. They include Renault's UNISURF as well as similar software created at General Motors and elsewhere. It was no coincidence that these companies also employed many of the researchers working on NURBS curves and surfaces and related techniques, and also collaborated with academic researchers in the same area.

One such program worth noting is CATIA, originally developed in the 1970s by the French aircraft manufacturer Avions Marcel Dassault. Instead of keeping CATIA in-house, Dassault turned it into a commercial product and sold it to other aerospace companies (including Boeing), automotive companies, and others.

In the 1990s the architect Frank Gehry (co-designer of Merriweather Post Pavilion) and his firm adopted CATIA for use in designing his breakthrough commission, the Guggenheim Museum in Bilbao, Spain (completed in 1997), and subsequent high-profile projects. Among these were the Experience Music Project in Seattle (completed in 2000) and the Walt Disney Concert Hall in Los Angeles (completed in 2003).

(The EMP in particular was one of the first major collaborations between Gehry and A. Zahner Company, another member of the Chrysalis design team, which fabricated the building's skin. Zahner's work on the Chrysalis will be discussed in a future article in this series.)

Gehry's success produced a lot of excitement about the possibility of using advanced nonlinear forms in architecture. However there were at least two factors that limited the adoption of CATIA and similar software by architects and made the impact of CAD software on architectural practice less revolutionary than it might otherwise have been.

First, CATIA and similar products and the computers needed to run them were very expensive: just the hardware alone for the Guggenheim Bilbao project was over half a million dollars at 1990s prices. (Gehry could afford it only because IBM loaned him the necessary graphics workstations.) Even today a full installation of CATIA or similar high-end CAD software can cost several thousand dollars per "seat", that is, for each person using the product. Thus only the largest architectural firms could afford to employ such advanced technology.

Second, CAD software was primarily used as an adjunct to traditional architectural drafting and modeling techniques. Gehry himself boasted of his inability to use a computer. Instead he created designs like the Guggenheim Bilbao by first modeling them in paper or cardboard. He then handed them off to more junior architects to create more refined models to be digitized and imported into CATIA for final refinement and generation of the actual instructions for builders and fabricators. (These are not necessarily paper blueprints. Instead the models are typically translated into instructions for computer-controlled tools.)

Thus although Guggenheim Bilbao and similar projects offered a glimpse of a new way of doing architecture, fully realizing that new way would await a new generation of powerful but low-cost hardware and software, and a new generation of architects, "digital natives" prepared to fully exploit the possibilities inherent in these new technologies.

An simple form-finding example by Marc Fornes using the Rhino 3D modeling program and the RhinoScript programming language. The script (the core code of which is shown) generates over a hundred random points within a tall rectangular box. For each new point the script finds the nearest neighboring point and draws a cone with its base at the new point and its tip at the neighboring point, and then a sphere centered at the new point. Image and script © 2007 Marc Fornes; used with permission.

Form finding

The road that led to Marc Fornes's work on the Chrysalis began in the early years of the 21st century, as the trends bringing faster, cheaper, and easier-to-use software and hardware gathered momentum. Fornes studied as an architect in France and then at the Architectural Association Design Research Lab in London, graduating in January 2004 with a Masters in Architecture and Urbanism.

After graduating from the DRL Fornes joined Zaha Hadid Architects in London, where he worked for over two years on a project to design a "médiathèque" (media library) for the French city of Pau, including an innovative self-supported roof constructed from a carbon fiber composite material. Although the Pau médiathèque project was ultimately cancelled for political reasons, much to the frustration of Fornes and his colleagues, it sparked his interest in complex curved surfaces and led him to begin experimenting with computational methods to design such surfaces.

That experimentation continued as Fornes moved to New York in the fall of 2006. Working under the project name "THEVERYMANY", Fornes took advantage of multiple technological advances, of which the most important was the creation of the PC-based 3D modeling software Rhinoceros, popularly known as Rhino or Rhino 3D.

Rhino was created by Robert McNeel & Associates ("McNeel"), a Seattle-based company that was founded in 1980 as an accounting firm and spent most of the 1980s and 1990s as a reseller of the CAD product AutoCAD and a marketer of AutoCAD add-on software. Eventually McNeel developed and sold Rhino as its own Windows-based 3D modeling product, with version 1.0 released in 1998.

McNeel followed several business practices unusual for traditional vendors of proprietary CAD software, practices more akin to those of then-new Internet companies like Netscape or developers of free and open source software: McNeel not only priced Rhino at a level affordable to small companies, including "boutique" architectural firms and individual architects, it allowed liberal downloads of evaluation copies at no charge. McNeel also followed the open source dictum "release early, release often" and distributed "beta" copies of new versions in development almost as soon as the previous versions were released, soliciting ideas for new features from its customers.

As a result Rhino quickly acquired an installed base of over a hundred thousand users, and (among other things) became the tool of choice for an emerging community of experimental architects and designers, including Marc Fornes. That community in particular explored the possibilities opened up by one key feature of Rhino, namely its ability to be driven by a computer program rather than by a human designer.

Each operation executed through Rhino's graphical user interface has an equivalent operation invoked by a textual command. Rhino supported the ability first to group multiple such commands together to execute a sequence of operations, and then provided full programmability using a scripting language (RhinoScript) and an associated application programming interface (API).6

Beginning in the mid-2000s Fornes and others pioneered techniques for form finding, that is, using the computer to generate potential structural forms from scratch, instead of using it simply as a way to digitally instantiate forms originally created by hand. They proselytized this new way of working through traditional in-person workshops and conferences as well as via the new medium of Internet blogs, including Fornes's own blog theverymany.net.

Fornes conceived of this work as experimental: starting with certain premises, assuming certain constraints, and then finding ways to create designs within those constraints. The designs were created using "very clear protocols, sets of mathematical relationships, algorithms, [and] geometrical transformations" (in other words, what Fornes referred to as an "explicit" way of working), which in turn were instantiated (or "encoded", as Fornes put it) in text files written in a particular computer programming language.

These designs also featured what Fornes referred to as "precise indetermination". "Precise" meant that the programs made little or no use of randomness (the example in the figure above is a rare exception) and thus produced consistently reproducible output from run to run (especially important for fabrication of the resulting design). However the designs were also "indeterminate", because the inherent complexity of the programs (including the interaction between different subprograms and their algorithms "fighting against each other") made it difficult for the designer to predict ahead of time exactly how a design would turn out.

At first Fornes's experiments were in digital form only, and in most cases they bore little resemblance to real-life structures. (See for example the above figure.) Many resembled nothing so much as exercises in advanced mathematics, which in a sense they were.

Following on from the original academic and industry researchers who created the mathematics and associated algorithms for NURBS curves and surfaces, Fornes and others used software like Rhino to play with the application of mathematical concepts to design: recursive definitions of surfaces and solids, fractals and L-systems, cellular automata, vector fields, Voronoi tesselations and Delaunay triangulations, and so on.7 Fornes's blog posts in 2006 and 2007 document this work, typically pairing striking images with the RhinoScript code or pseudocode that produced them.

Fornes also combined his day-to-day work as an architect with an increasingly heavy schedule of academic work at Columbia University in New York, the University of Southern California in Los Angeles, die Angewandte (the University of Applied Arts) in Vienna, and elsewhere, as well as instructional classes in RhinoScript programming for McNeel and related activities at workshops, conferences, and exhibitions.

Two stages in the assembly of Y/Surf/Struc (part of the permanent collection of the Centre Pompidou in Paris): an assembled module of the structure surrounded by cut strips of aluminum sheet to be riveted together to form other modules (L), and the assembly team connecting the modules to form the final structure (R). (Click for a higher-resolution version.) The striped effect is produced by some aluminum strips being painted on one or both sides. Images © 2011 Marc Fornes; used with permission.

Iterative improvement

Although the designs produced by Marc Fornes and others could be viewed as striking works of art, Fornes conceived of himself not as an artist but as an architect, someone whose designs were actually built, or at least buildable.

Thus beginning in 2008 Fornes and his associates in THEVERYMANY began work on a series of what he called "prototypical structures": structures not intended for permanent use by actual inhabitants, but rather created to explore various design techniques and methods for fabrication and assembly. Fornes and his team both designed the structures and assembled them, thus echoing the ancient tradition of folk architecture based on nonlinear forms, in which the roles of the "architects" and the "builders" were blurred.

In creating these prototypical structures Fornes and his associates also adopted an approach reminiscent of both traditional architecture and the Silicon Valley dictum "fail fast, fail often". (Fornes hyberbolically referred to several of these projects as "big-time failure[s]".) Any problems encountered in creating the structures were treated not as fatal errors but as opportunities to learn what went wrong and fix it for the next iteration.

One of the first problems that presented itself was translating the curved surfaces of the design into flat elements that could be fabricated (e.g., in sheet plastic or aluminum) and then assembled. Because at the time there was no automated way to do this for arbitrary elements, Fornes created ways to design surfaces that both provided for three-dimensionality (necessary to create self-supporting structures) and also were composed of a relatively small number of unique regular elements that could be relatively easily arrayed on a sheet of material and then cut out and riveted together.

But even though the parts were relatively easy to fabricate, assembling them into an actual structure proved very difficult, requiring constant referral to the original digitally-rendered design in order to determine which elements attached to which others. In the end Fornes and his team were never able to complete the assembly of one such structure—although as it turned out the gallery for which it was intended had never seen the correct rendering, liked the structure as is, and even invited them to create another one.

In order to reduce assembly time Fornes and his associates adopted the practice of tagging the individual fabricated elements with encoded information regarding the other elements to which they connected. This reduced the need to refer back to the digital model and decreased assembly time by an order of magnitude.

Still other problems soon presented themselves. In scaling up to larger structures Fornes used thicker materials for the structural elements. This caused the weights of the structures to increase, which in turn made it more difficult for the structures to bear their own "dead load" and stand up by themselves. Because all elements of the structures had to be riveted to each other using pre-made holes, Fornes and his team of assemblers also encountered problems when tiny misalignments in connecting the elements built up and caused problems when assembling the final elements in the structures.

Advances in CAD software helped with some of the problems previously encountered, as the popularity of the Rhino 3D modeling product spurred the growth of a "ecosystem" of add-on products and related capabilities. For example, McNeel's Grasshopper add-on provided a visual programming language to supplement traditional RhinoScript programs, while the third-party product RhinoNest optimized the process of "nesting" arbitrary structural elements onto flat sheets to be laser cut or milled with minimal wasting of material.

These advances were not panaceas. Fornes and his designers might now be able to create designs featuring arbitrarily-large numbers of unique structural elements and to nest those elements onto sheets for cutting or milling, but assembling such elements was still time-consuming—so time-consuming as to often be impractical for a small team working against a deadline.

One way Fornes reduced assembly time was to combine multiple individual elements into one elongated element, producing strips of material to be further combined into structural components. (See the figure above, in which painting some of the strips made this technique visible as colored stripes on the final structure.) But building a structure out of long strips could lead to other problems, as Fornes found when he designed a structure to be made of wood veneer and accidentally nested the strips in a way that went against the grain of the wood, thereby weakening them. (The resulting structure collapsed while being transported to the exhibition site.)

Nonetheless Fornes and his associates perservered in their pursuit of learning through failure and iterative improvement, and succeeded in creating more and more striking and successful projects: structures large enough to be experienced as spaces rather than just as sculptures, structures whose unassembled elements were small and light enough to be transported halfway around the world in the team's suitcases (echoing the experiences of nomads who carried their homes with them), structures designed for easy storage when necessary, structures made of aluminum, or plastic, or carbon fiber—all leveraging an increasingly sophisticated repertoire of design, fabrication, and assembly techniques.

The Chrysalis design as rendered, showing the pleats in the surface. (Click for a higher-resolution version.) Adapted from the Inner Arbor Trust presentation to the Howard County Design Advisory Panel on February 26, 2014. Image © 2013 Marc Fornes; used with permission.

The genesis of the Chrysalis

As the second decade of the 21st century began, Marc Fornes received increasing attention as an architect to watch. In 2010 he quit his day job at a large architectural firm and converted THEVERYMANY from an informal project into an independent design studio, gaining more freedom to pursue his own projects. (As he put it to writer Terri Peters, "I realized nobody is ever going to commission me to do what I want to do, so I thought, what can I commission myself to do?")

The years 2011 and 2012 saw a number of new projects for THEVERYMANY, including for the Centre Pompidou (shown above), FRAC Centre, and Atelier Calder in France, and Washington University at St Louis and Art Basel Miami in the US. Those years also marked the beginning of the events that would eventually lead to the creation of the Chrysalis.

As previously described, after his appearance at the Columbia Association resident "speak out" in September 2011 Michael McCall of Strategic Leisure began thinking seriously about creating a concept plan for a new park in Symphony Woods. Throughout 2012 McCall created a series of presentations outlining such a plan.

When creating Columbia, Jim Rouse had sponsored the work of Frank Gehry when Gehry was just starting his career; the results included Merriweather Post Pavilion and the Rouse Company headquarters building. In creating his concept plan for Symphony Woods (at the heart of Columbia), Michael McCall, formerly a Vice President at Rouse's Enterprise Development Corporation, saw the opportunity to emulate his mentor by calling upon the talents of a new generation of promising architects. Thus when McCall created his concept plan presentations, to inspire his audiences and show how the plan might be implemented he highlighted the work of various innovative architects and artists, including in particular Marc Fornes.

In February 2013 McCall made a public presentation of the new "Inner Arbor" concept plan proposed by the Columbia Association as an alternative to the previous "Paumier plan". Again this presentation mentioned Marc Fornes, in the context of the "Treehouse amphitheater" element of the concept plan.

In the subsequent months the Inner Arbor Trust was officially established and began the process of selecting designers for the various plan elements. In a presentation to Leadership Howard County in September 2013 McCall again mentioned Fornes as one of the designers who were candidates for possible commissions.

In that same presentation McCall also laid out the goals of the amphitheater element of the Inner Arbor plan: to serve as a stage for performances (including as a secondary stage for Merriweather Post Pavilion), as a pavilion for family reunions, church picnics, weddings, and similar events, and as a sculpture that would be a beautiful addition to the park during other times.

In November 2013 the Inner Arbor Trust formally announced the selection of Marc Fornes as part of the design team for the Inner Arbor plan, what Michael McCall termed the "Designers of Delight". Shortly thereafter, at a community meeting on December 2, Fornes presented the design for what was now referred to as the "Chrysalis".

The underlying quadrilateral mesh of the Chrysalis design as seen from above after inflation. (Click for a higher-resolution version.) The darker lines in the mesh mark the peaks of the pleats. Adapted from the Inner Arbor Trust presentation to the Howard County Design Advisory Panel on February 26, 2014. Image © 2013 Marc Fornes; used with permission.

Mesh inflation

The design of the Chrysalis was created using a process Fornes called "pleated inflation", a variant of "mesh inflation". The technique of mesh inflation was made possible by the increasingly sophisticated applications built on the Rhino modeling software, including the Grasshopper visual programming language, the Kangaroo physics simulation add-on to Grasshopper, and similar tools.

In mesh inflation the tools start with a flat surface of a certain shape specified by the designer. The form of the surface will determine the final form of the structure. For example, in the Chrysalis mesh inflation (see the first figure above) the initial surface (outlined in yellow) has nine "projections" or "peninsulas" that will end up as the legs of the Chrysalis.

The tools then divide up the surface to create a mesh of four-sided shapes (quadrilaterals). In the case of the Chrysalis the lines of the mesh run "lengthwise" along the projections (purple in the first figure above) and "crosswise" across them (blue in the figure). The way those projections (or more specifically, the lengthwise lines of the mesh) join to each other then determines the way the "vaults" of the Chrysalis intersect with each other.

Once the mesh is defined, the tools then treat the lines of the mesh (the sides of the quadrilaterals) as if they were springs (of varying degrees of stiffness) connecting together the vertices of the mesh (the places where the lines of the mesh cross) and providing tension between them. The exact simulated stiffnesses can be tweaked by the designer to achieve various effects.

Some vertices at the edge of the mesh are constrained to remain attached to the "ground". These places are to be the bases of the "legs" of the final structure. (For the Chrysalis these vertices are the ones at the ends of the nine projections of the initial surface.)

The tools then simulate an upward force applied to the vertices of the mesh. The simulated force causes the vertices to move vertically into the "air", but they are constrained by the tension placed on them by the simulated springs between them, or (for designated vertices at the edge) by their attachment to the "ground".

Other simulated forces can be applied in other directions, most notably outward from the surface as it evolves. The net effect is that the initially flat mesh "inflates" into a 3-dimensional structure, analogous to a balloon being blown up or an inflatable tent being filled with air.

Fornes used the mesh inflation technique (what he called "a computationally derived dynamic spring network with behavioral attributes") in designing the sculpture "Vaulted Willow" for Borden Park in Edmonton, Alberta. The first figure above and its linked video show a similar technique as used in creating the Chrysalis design.

The Chrysalis design as presented in the pre-submission meeting and to the Design Advisory Panel was more complicated than could be produced using the same type of mesh inflation used for the Vaulted Willow project. Instead Fornes used a variant technique he called "pleated inflation", previously used in designing a structure of the same name in Argelès-sur-Mer in France.

In the pleated inflation technique certain "lengthwise" lines through the original mesh and their associated vertices are marked out as special. During the inflation process the simulated forces and/or tensions are varied such that the resulting surface is not smooth, but instead assumes a corrugated or pleated appearance, with the peaks of the pleats running along the previously marked lines.

In the Argelès-sur-Mer amphitheater, which is built solely from flat aluminum shingles folded and then riveted together, the resulting pleats supply stiffness to the overall architectural form and help ensure the integrity of the structure. The pleats in the Chrysalis also provide structural integrity, supplemented by additional elements as discussed below. In addition the Chrysalis pleats help channel rain water and snow melt off the structure.

The Chrysalis under construction in the fall of 2016. (Click for a higher-resolution version.) Compare to the design rendering above. Image © 2016 Inner Arbor Trust; used with permission.

Sculpture, pavilion, stage

Recall again the three roles of the Chrysalis: as a sculpture, a pavilion, and a stage. As a sculpture the Chrysalis follows in the tradition of previous THEVERYMANY projects in its nonlinear form, though its shape is relatively simple and straightforward compared to projects like Y/Surf/Struc (shown above).

Though the Chrysalis design has a simpler shape than that of Y/Surf/Struc, it makes more sophisticated and subtle use of color. In structures like Y/Surf/Struc color was used mainly to highlight the underlying plan of the design—as Marc Fornes remarked, "It's not for [the color] that we got invited [to the Centre Pompidou]."

Fornes used color more imaginatively and playfully in later projects like Vaulted Willow, befitting its role as a public art piece for a park. The aluminum shingles forming the structure go from predominantly purple and blue at the base to blue and green and then to green and yellow at the top, with the eye perceiving a gradient of color built from a series of single-color shingles.

The Chrysalis uses a similar scheme, albeit with a more restricted range of colors (being similar to the Pleated Inflation structure in that respect). As a larger structure in a wooded setting, its colors span a range of greens to echo its surroundings. As with Vaulted Willow, the Chrysalis as constructed (see the figure above) shows the effect of a sophisticated "dithering" technique, designed to use a limited color palette (only four colors of shingles in the Chrysalis) to simulate a broader range of colors. The end effect as perceived by the eye is a relatively smooth gradient running from a darker green at the bottom to a lighter green at the top.

In its role as a pavilion the Chrysalis differs from previous THEVERYMANY projects mainly in being designed to provide a solid shell. Previous projects, including the Pleated Inflation amphitheater, used shingles that were perforated in various ways, using a technique to determine the shape and location of the perforations that Fornes calls "agent-based porosity". Since the Chrysalis is intended for uses such as picnics and weddings that might be held in inclement weather, its surface is solid and designed (using the pleats) to channel water away from participants.

The Chrysalis is also considerably larger than any other THEVERYMANY project, easily twice the width, depth, and height of its "little brother", the Pleated Inflation structure. This means that the area under the shell (about five thousand square feet in total) is much larger than that associated with the other projects, providing sufficient room to shelter fairly large gatherings.

The final role of the Chrysalis, as a performance stage, put the most demands on the design. The Chrysalis stage is actually two stages in one: the larger or "alpha" stage facing west, and a smaller "beta" stage facing south. These stages were not intended just for community and school plays and concerts and other relatively small-scale events. Instead the alpha stage was also intended to serve as a secondary stage for Merriweather Post Pavilion, for example during large music festivals.

Over the years the increased appetite of concert-goers for elaborate productions has led acts to impose ever greater technical requirements on the venues seeking to host them: more stage space, greater electrical capacity, and—most important—the ability to hang ever larger and heavier lighting rigs and audio equipment.

In the case of Merriweather Post Pavilion this trend led to the eventual replacement of the existing stage and stagehouse with larger facilities. In the case of the Chrysalis it greatly increased the loads that the Chrysalis would have to bear, as specified in the technical requirements worked out among the Inner Arbor Trust, I.M.A. (the operators of Merriweather Post Pavilion), and other parties.

In particular the Chrysalis shell would have to support a much greater load due to hanging equipment (up to 40,000 pounds in total per the technical requirements), and a correspondingly greater risk of having "point loads" damage the structure. (For example, think of roadies inadvertently attaching heavy equipment at one place on the structure without balancing the load at attach points elsewhere.)

This load was in addition to the static load of the structure's own weight, potential additional load due to snowfalls, and potential dynamic loads due to high winds hitting the structure from various angles. The total surface area upon which wind can act is much greater for the Chrysalis than for other THEVERYMANY projects, and the resulting wind force correspondingly larger. The planned-for wind load, at about 60,000 pounds, is actually higher than the anticipated load due to theatrical equipment.

Given the anticipated and planned-for loads, the Chrysalis does not rely solely on pleated metal shingles to provide structural integrity. The Chrysalis design uses pleated shingles for the outer surface and then supplements them with an inner framework of curved steel elements underneath the shingles. (See future articles in this series for more information on this steel framework and the means by which the shingles are attached to it.)

A close-up of the Chrysalis shingles showing the different colors used. (Click for a higher-resolution version.) Image © 2016 Inner Arbor Trust; used with permission.

The significance of the Chrysalis

The Chrysalis is special in many ways. First, it represents the largest structure yet designed by Marc Fornes, and in its role as a modern performance stage must meet more demanding real-life requirements than any previous THEVERYMANY project. Its creation marks another step in the evolution of Fornes as an architect and THEVERYMANY as a studio, consistent with his goal to "learn, grow, and grow in scale".

Second, for the Inner Arbor Trust the Chrysalis is the first element of the Inner Arbor plan to take tangible form. Its successful completion confirms the wisdom of the Columbia Association in investing the Inner Arbor Trust with the responsibility of creating a new park for Symphony Woods, and helps position the Trust for future success in carrying out the remainder of the Inner Arbor plan.

Finally, for the people of Columbia and Howard County, who funded the design and construction of the Chrysalis and will be its primary users, the Chrysalis is a unique and beautiful addition to downtown Columbia, fully capable of fulfilling its roles as stage, pavilion, and sculpture, and a structure that—along with a renovated Merriweather Post Pavilion—will serve as an anchor around which the vision of Merriweather Park at Symphony Woods can be realized.

For further exploration

This article is based on material from a variety of online sources, including the following:

For more on Bézier and NURBS curves see the following:

"On the Spline: A Brief History of the Computational Curve", by Alastair Townsend. A non-mathematical explanation of the historical and technical aspects of Bézier and NURBS curves.

"A History of Curves and Surfaces in CAGD", by Gerald Farin. A more technical history of computer aided geometric design.

"My Time at Citroën", by Paul de Casteljau. An autobiographical article that provides some amusing insights concerning de Casteljau and the environment in which he worked at Citroën.

"NURBS-Calculator". An interactive web-based demo that allows you to manipulate and create NURBS and Bézier curves. (You can even use it on smartphones and tablets.)

For more on architectural design software and associated techniques see the following:

"The Software Behind Frank Gehry's Geometrically Complex Architecture", by Lian Chang. Outlines the history behind the adoption of CATIA for Frank Gehry's projects.

"The Way of Rhino" (part 1, part 2, part 3, and part 4), by Randall Newton. A 2007 series of articles providing an in-depth look at Robert McNeel & Associates, creators of Rhino, and their impact on the CAD market.

"Rhino Grasshopper", by Martyn Day. A 2009 article describing the then-new Grasshopper add-on to Rhino for visual scripting of geometry.

"Grasshopper Primer", by Mode Lab. For readers who are programmers this offers an interesting glimpse into a visual programming language specialized for manipulation of geometric objects.

For more on Marc Fornes and his work see the following:

theverymany.com is the most comprehensive source of information on Fornes and the work of THEVERYMANY. In addition to the projects highlighted on the main page, the archived blog posts on theverymany.com form a continuous record of Fornes's work from late 2005 to 2014. (Keep scrolling to read earlier posts.) The posts in 2006 and 2007 are particularly interesting for their inclusion of sample RhinoScript code.

"Marc Fornes Creates Spaces He Has Never Seen Before", by Terri Peters. A 2010 article that provides a good summary of Fornes's design philosophy and working methods.

"Tech Specs: Marc Fornes, Founder of THEVERYMANY", by Mason Currey. A 2015 article in which Fornes discusses the computer software and other tools he uses in his work.

scriptedbypurpose. A 2007 exhibition curated by Fornes, its website contains many examples of experimental designs produced by RhinoScript code.

(n)Certainties (original, v2.0, v3.0, v4.0, and v5.0). A series of workshops held at Columbia and USC from 2007 to 2009 by Fornes, Francois Roche, and Stephan Henrich, their websites also contain many experimental designs with accompanying RhinoScript code.

"D01 06 Marc Fornes Structurant Bark" [40-minute video]. A presentation by Marc Fornes at the symposium "PROTO/E/CO/LOGICS 002: The Field is Open", held September 1-2, 2012, in Rovinj, Croatia. It includes discussions of the series of "prototypical structures" and lessons learned in creating them.

"Unabashed Designers of Delight" [121-minute video] (November 18, 2013). A presentation introducing the design team for the Inner Arbor plan. It includes a presentation by Marc Fornes beginning at 58:26 that discusses a number of THEVERYMANY projects, including the amphitheater at Argelès-sur-Mer.

"The Art of the Prototypical" [74-minute video] (October 26, 2015). A presentation by Marc Fornes at his alma mater, the Design Research Lab of the Architectural Association in London. It includes a discussion of more recent projects, including brief comments on the Chrysalis.

For more on the Chrysalis amphitheater and its origins in the Inner Arbor concept plan, see the following:

Michael McCall's presentation of the Inner Arbor concept plan to Leadership Howard County [33-minute video] (September 20, 2013).

The Chrysalis portion of the Inner Arbor pre-submission community presentation (December 2, 2013).

Michael McCall presentation to the Howard County Design Advisory Panel [20-minute video] (February 26, 2014).

"Chrysalis mesh inflation" [68-minute video]. A video showing the process of mesh inflation for the Chrysalis. Note that most of the video is blank, with the only content being the initial two minutes and from 41:40 on.

"Mesh pleated inflation, Argeles" [2-minute video]. A brief video showing the process of mesh inflation for the "Pleated Inflation" amphitheater in Argelès-sur-Mer, including the creation of the pleats in the surface (not shown in the equivalent Chrysalis video).

For more of my opinions on and explanations of various aspects of the Chrysalis and Merriweather Park at Symphony Woods, see the Inner Arbor-related posts in the series "The Inner Arbor plan takes shape" and elsewhere on this blog. (Note that some of these posts contain outdated information relating to park features that were later dropped or revised.)

Bernstein polynomials are a special type of polynomial discovered in the early 1900s by the mathematician Sergei Natanovich Bernstein, who showed that they could be used to approximate any continuous function on a closed interval. For example, the Bernstein polynomials of degree 2 are (1 - t)2, 2t(1 - t), and t2. (In standard form these are t2 - 2t + 1, -2t2 + 2t, and t2.) Note that only the first polynomial is nonzero when t = 0, and only the last polynomial is nonzero when t = 1; this is a general property of Bernstein polynomials. ↩

More specifically, the point on the curve corresponding to a particular value of t is a linear combination of the control points, with the coefficient for each control point being the value of that point's associated Bernstein polynomial for that value of t. ↩

The work at Citroën was first referenced in the public literature in 1971, and de Casteljau's role in that work was first revealed in the late 1970s. Many years later de Casteljau was honored by the Solid Modeling Association, receiving its 2012 Bézier Award. ↩

In mathematical terms this smoothness has to do with the continuity of the derivatives of the function defining the curve in terms of its underlying parameter: C0 continuity means the curve's function is continuous, C1 continuity that the first derivative of the function is continuous, C2 continuity that the second derivative is continuous, and so on. If a curve lacks C0 continuity at certain points then it will have gaps at those points, and if it lacks C1 continuity it will have kinks. C1 continuity (or a weaker form known as G1 geometric continuity) is the minimum requirement for the curve to appear smooth, with a fully-pleasing smoothness typically requiring at least C2 (or G2) continuity. ↩

The order of a spline function is one greater than the degree of the polynomial expressions of which it is composed. Thus a spline function containing cubic polynomials (i.e., of degree 3) has order 4. The order in turn determines the number of B-spline functions for that type of spline—there are four such functions in our example. ↩

As noted, Rhino began life as a product available solely for Microsoft Windows. The scripting language RhinoScript was based on the language used in Microsoft's Visual Basic product. Later McNeel added the ability to use the popular open source programming language Python as an alternative to RhinoScript, and ported Rhino to Mac OS X. ↩

If you're reading these footnotes you presumably know what recursion and fractals are. See Wikipedia for more information on L-systems, cellular automata, vector fields, Voronoi tesselations and Delaunay triangulations. ↩

Frank firstname.lastname@example.com explore the design of the Chrysalis and the work of Marc Fornes, its designer.Creating the Chrysalis: Politics and process2016-01-17T08:30:00-05:002016-01-17T08:30:00-05:00https://civilityandtruth.com/2016/01/17/creating-the-chrysalis-politics-and-process

Participants in the Chrysalis groundbreaking ceremony, representing the various entities involved in Merriweather-Symphony Woods development. From left to right: It's My Amphitheater President Brad Canfield and General Manager Jean Parker (operators of Merriweather Post Pavilion), the Downtown Arts and Culture Commission Acting Executive Director Ian Kennedy, Maryland State Delegate Clarence Lam, Inner Arbor Trust Chair Martin Knott, Howard Hughes Vice President of Development Greg Fitchitt, Howard County Council Member Greg Fox, Howard County Executive Allan Kittleman, Inner Arbor Trust President and CEO Michael McCall, Howard County Council Chair Mary Kay Sigaty, Columbia Festival of the Arts Executive Director Todd Olson, Columbia Association President and CEO Milton Matthews, Howard County Council Member Jon Weinstein, and Howard County Council Member Dr. Calvin Ball. Click for a higher-resolution version. Image © 2015 Inner Arbor Trust; used with permission.

tl;dr: I discuss the various institutional activities related to implementation of the Inner Arbor plan, with a focus on the Columbia Association, the Inner Arbor Trust, and the Howard County government, including its planning process.

This article is one in a series exploring in depth the creation of the Chrysalis amphitheater in Merriweather Park at Symphony Woods in Columbia, Maryland. For the complete list of articles please see the introduction to the series.

The previous article in this series described the vision and strategy for creating a new park in Symphony Woods according to the Inner Arbor plan. This article picks up where the first article in the series left off, describing the process that led to the Columbia Association's adopting the Inner Arbor plan and creating the Inner Arbor Trust as an independent organization to implement it, along with the history of the Inner Arbor Trust and related events up to the present.

Organizations and their roles

As in the previous events relating to downtown Columbia development in general and Symphony Woods in particular, multiple organizations played a role in this history in addition to the Inner Arbor Trust itself:

The Columbia Association was at the center of the story, at least initially, due to its ownership of the Symphony Woods, its plan in progress for developing a park on that property, and its creation of and ongoing relationship with the Inner Arbor Trust.

The Howard County government served variously as a promoter of downtown Columbia development (both formally through the Downtown Columbia Plan and informally in various ways), the regulator of such development (through the Department of Planning and Zoning, the Planning Board, and the Design Advisory Panel), a funder of Symphony Woods development (through the County Executive and County Council), and a future user of park features (through the Department of Parks and Recreation and its sponsorship of the Wine in the Woods festival).

The Howard Hughes Corporation had by this time assumed the role previously filled by General Growth Properties (and before GGP the Rouse Company) as the owner of Merriweather Post Pavilion, situated within and surrounded by Symphony Woods. Howard Hughes and It's My Amphitheater, Inc. (the operators of the pavilion) played key roles in promoting integration of Symphony Woods development with redevelopment of Merriweather Post Pavilion. They were joined by the Downtown Columbia Arts and Culture Commission, the county-created nonprofit organization slated to take over ownership of the pavilion property from Howard Hughes.

Other players included the state of Maryland (which had previously provided a grant to CA for Symphony Woods development) and the Columbia Festival of the Arts (a future user of park features).

2012: Rethinking

As of the fall of 2012 the Columbia Association was faced with a decision on what to do about Symphony Woods development. Although the Howard County Planning Board1 had nominally approved the CA-created Final Development Plan for Symphony Woods Park (FDP-DC-MSW-1, based on the so-called "Paumier plan"), the Planning Board had attached recommendations to that approval that in practice required a major rethink of the original plan.

At that point after two years of work the Columbia Association had a diagram for a pathway system and a concept design for a fountain, but no detailed designs for other park features. CA was in the position of having to make significant changes to its existing design prior to taking them to the next stage of the county planning process (i.e., in the form of a Site Development Plan), as well as having to flesh out those parts of the design yet unfinished. Besides the impact on CA staff, the financial stakes were also high since the costs of preparing and implementing an SDP would be considerably greater than those incurred for the FDP.

The Columbia Association had been urged for some time to coordinate its plans with those being created by the Howard Hughes Corporation. The previous April Howard Hughes had recommended that CA look at a new concept plan being created by Michael McCall for the Merriweather-Symphony Woods neighborhood. This advice was apparently being echoed by others.2

The CA board considers alternatives

On October 5, 2012, Columbia Association President and CEO Phil Nelson recommended that the CA board devote time in its first October meeting to discussing various questions relating to Symphony Woods development, including the possibility of partnering on Symphony Woods development with another organization, and of revising the Symphony Woods plan to take into account planned redevelopment of Merriweather Post Pavilion.

On October 11 the Columbia Association Board of Directors held a work session at which Phil Nelson discussed options for Symphony Woods development and the CA board took a number of straw polls on how to move forward. Those board members present (all except Cynthia Coyle) expressed unanimous support for the idea of forming a separate organization to develop Symphony Woods. Although the work session was public, no one spoke during the Resident Speak Out portion of the meeting—in fact no one from the general public attended the board meeting at all (according to a later recollection by board member Andy Stack).

Thus the possibility that the Columbia Association might change its strategy for Symphony Woods development, as well as the behind-the-scenes work to create a new concept plan, went unnoticed and unremarked for the most part, as the CA board devoted its meetings to other topics the rest of the year.

2013: Creating

That period of relative quiet ended in late January 2013 with the public unveiling of the Inner Arbor concept plan created by Michael McCall of Strategic Leisure. (See the previous article in this series for an in-depth discussion of this concept plan.)

Implementing the Inner Arbor plan via a separate organization

After the Columbia Association released information on the concept plan on January 18, at the January 24 CA board meeting CA President Phil Nelson presented several recommendations to the board:

That the Columbia Association adopt the Inner Arbor concept plan as the overall framework to guide future development of Symphony Woods as a whole.

That CA adopt Symphony Woods as the preferred location for a new CA headquarters. This proposal had been discussed back in 2005, and was included in the Inner Arbor concept plan as a suggestion for the eastern part of Symphony Woods.

That the CA board instruct CA management to establish a separate "Trust" to carry out development of Symphony Woods on behalf of CA.3

That CA enter into a perpetual easement agreement providing the trust organization the necessary rights to carry out development according to the Inner Arbor concept plan.

That CA transfer to the trust organization funds that CA had allocated for Symphony Woods development in its current and future budgets.

Nelson also noted that, per the Howard County Department of Planning and Zoning, development of the northern section of Symphony Woods could proceed according to the already-approved Final Development Plan. (As previously discussed, the northern section of Symphony Woods encompassed the "public park" envisioned in the Inner Arbor concept plan, as distinguished from the "performance park" and "curated park" in the eastern and southern sections. The approved FDP incorporated not only a pathway system but also various proposed park elements in addition to a fountain, including an amphitheater, café, play area, and public art.)

On January 31 Michael McCall presented the Inner Arbor concept plan at a public meeting sponsored by the Columbia Association. On February 7 CA President Phil Nelson sent a memo to the CA board with an expanded and refined set of recommendations, proposing that CA

adopt the Inner Arbor concept plan;

create a separate nonprofit organization that could qualify for 501(c)(3) tax-exempt status as the vehicle to carry out the plan;

negotiate a perpetual easement on the Symphony Woods property with the new organization; and

provide initial funding of $1.6 million to the new organization (representing CA's already budgeted amount for Symphony Woods development).

Nelson subsequently sent a revised memo to the Columbia Association Board of Directors on February 13, formalizing the recommendations made in the February 7 memo in preparation for the board's consideration of them.

On February 14 the Columbia Association Board of Directors voted 8-2 to accept Nelson's recommendations and move forward with the creation of a separate "Symphony Woods Trust". Voting in favor were Regina Clay, Ed Coleman, Tom Coale, Michael Cornell, Gregg Schwind, Andy Stack, Suzanne Waller, and Shari Zaret; voting against were Cynthia Coyle and Alex Hekimian.

Inner Arbor supporters and opponents

However this overwhelming approval by the Columbia Association Board of Directors did not end the dispute over CA's change in direction regarding Symphony Woods development. The ensuing controversy in some ways mirrored the previous controversy in 2005 over General Growth Properties's proposed master plan for downtown Columbia.

Several opponents of the previous GGP plan, including former CA board members Barbara Russell and Russ Swatek and community activist Alan Klein of the Coalition for Columbia's Downtown, argued against the Inner Arbor concept plan for its proposal to put buildings in Symphony Woods, and also charged that the process of adopting the plan did not reflect adequate time for public input and discussion. They were joined in their opposition by Cy Paumier and some of his associates, who lobbied the CA board both privately and publicly for retention of the prior plan for Symphony Woods Park that they had created.

Beyond the Columbia Association Board of Directors itself, strong Inner Arbor plan supporters first and foremost included county elected officials, with Howard County Executive Ken Ulman making a public statement in support of the concept plan when it was first unveiled. Howard County Council members Calvin Ball and Mary Kay Sigaty followed up with a public letter referring to it as a "bold vision" in line with the Downtown Columbia Plan's vision of a "cultural park where the landscape becomes a setting for arts, cultural and civic uses", and County Council member Jen Terrasa argued in another public letter that the plan "invites the community back and creates a heart for Columbia right in Symphony Woods". Other expressions of support came from people and organizations previously promoting downtown Columbia development, including George Barker of Bring Back the Vision, Brian Dunn of Columbia 2.0, Phil Engelke of the New City Alliance, and Ian Kennedy of Awesome Columbia, as well as from various local bloggers, including Dennis Lane, Julia McCready, and Bill Woodcock, and (last but not least) from the editorial board of the Baltimore Sun.

The Columbia Association Board of Directors election on April 20, although marked by typical low turnout,4 was seen by some as a referendum on the Inner Arbor plan. Plan opponent Russ Swatek and the relatively neutral Nancy McCord defeated plan proponents Ed Coleman and Regina Clay. However although reduced the pro-Inner Arbor plan majority on the CA board remained intact, with at least six of ten board members counted as clear supporters.

(In June later that year Tom Coale, one of the highest-profile champions of the Inner Arbor plan, resigned from the Columbia Association Board of Directors in order to run for the Maryland House of Delegates seat in District 9B. He was replaced by Tom O'Connor, also a supporter of the Inner Arbor plan. Thus the relative balance between supporters and opponents on the CA board remained unchanged.)

Creating the Inner Arbor Trust and ensuring its independence

Meanwhile creation of the separate trust organization proceeded as previously approved by the Columbia Association Board of Directors back in February. On April 26 lawyers representing CA incorporated the new organization in Maryland as the Inner Arbor Trust, Inc., "to promote and support the revitalization of the Merriweather-Symphony Woods Neighborhood" in a manner compatible with IRS regulations relating to 501(c)(3) tax-exempt status. On May 10 the Inner Arbor Trust Board of Directors first met and adopted a set of bylaws.

As originally envisioned by the Columbia Association Board of Directors, and as specified in the articles of incorporation, the Inner Arbor Trust had a five-member board, with two members being elected from the CA board and the CA President being a third member. On March 28 the CA board elected Ed Coleman and Gregg Schwind to be its representatives on the Inner Arbor Trust board, with CA President Phil Nelson also taking a Trust board seat by virtue of his position as CA's President and CEO. (The first at-large Trust board members were Deborah Ellinghaus and Kent Humphries.)

However one of the first actions of the Inner Arbor Trust Board of Directors, taken at its initial meeting, was to expand the board from five members to seven, including four independent directors not associated with the Columbia Association. According to CA General Counsel Sheri Faranoff this was motivated by a need to show that the Inner Arbor Trust board was independent of and not controlled by the CA board in order to make a case to the IRS for 501(c)(3) tax-exempt status.5 At the May 10 meeting this change was approved unanimously by the Inner Arbor Trust board, including the CA-associated board members, and reflected in the bylaws as signed and dated May 13.

The Inner Arbor Trust Board of Directors then proceeded to elect two new members not associated with the Columbia Association, Gill Wylie and Beverly White-Seals. White-Seals, a former attorney for the Rouse Company, was also appointed Secretary for the Trust. Ed Coleman remained on the Trust board despite losing his CA board seat only a few weeks before, as the CA board did not appoint a new representative to take his place. Finally at its second meeting on May 30 the Trust selected as its Treasurer Rafia Siddiqui, the former Chief Financial Officer of the Columbia Association.

Once created the Inner Arbor Trust turned to the various tasks before it—negotiating an easement with the Columbia Association, applying for IRS 501(c)(3) tax-exempt status, acquiring funding, and refining the Inner Arbor plan—under the direction of Michael McCall, who had been appointed President and CEO of the Inner Arbor Trust, and whose firm Strategic Leisure, Inc., had been retained by the Inner Arbor Trust to provide support for Trust activities.

Howard County funding of the Inner Arbor project

May 2013 also saw the Howard County Council—via an amendment by Council member Mary Kay Sigaty with the support of Howard County Executive Ken Ulman—unanimously appropriate up to $3.5 million in the FY14 budget for "planning, design, engineering, and construction costs for an amphitheater located in Symphony Woods". This was on top of the previous commitment by CA to provide $1.6 million in initial funding for the Inner Arbor Trust. (An initial $450,000 of this commitment was paid by CA to the Trust prior to July 31.)

Designing the public park

During the summer of 2013 the Inner Arbor Trust began selection of design firms and architects for the various proposed park features. On September 20, as part of a presentation to Leadership Howard County, Michael McCall announced the selection of Martha Schwartz Partners as landscape designers and artists and Baltimore firm Mahan Rykiel Associates as the landscape architect of record, along with the Burtonsville firm Gutschick, Little & Weber as the civil engineers. (Mahan Rykiel and GLW had previously been involved with the work leading to the Final Development Plan.)

Two months later, on November 18, Michael McCall introduced the full design team (dubbed by him the "Designers of Delight"), adding THEVERYMANY (Marc Fornes), nArchitects (Mimi Hoang and Eric Bunge), and Arup (represented by Raj Patel) to Martha Schwartz Partners (represented by Martha Schwartz) and Mahan Rykiel Associates (represented by Scott Rykiel).

The Inner Arbor Trust closed 2013 with three important milestones:

First, on December 2 the Trust made its first public presentation of its plan for the northern "public park" portion of Symphony Woods, including the Chrysalis amphitheater, Butterfly guest services building, Caterpillar sculptural berm (embodying the "Art of Bounds" theme), and other park features. This presentation marked the "pre-submission meeting" stage of the Howard County planning process prior to submittal of a formal Site Development Plan. The meeting featured presentations from all members of the design team, as well as a presentation by Biohabitats, the firm hired by the Inner Arbor Trust to assist with environmental issues, including stream restoration.

The easement agreement between CA and the Inner Arbor Trust

Second, on December 11, 2013, the Inner Arbor Trust reached an agreement with the Columbia Association for a perpetual easement for the 37 acres of Symphony Woods, as well as for an additional 15 acres of open space in the Crescent property to be donated to CA in future by the Howard Hughes Corporation. The easement grant was split into multiple phases:

Phase 1 included the "public park" portion of Symphony Woods outlined in the concept plan, along with additional acreage adjacent to Merriweather Post Pavilion to the east, south, and west. (The inclusion of this additional land would prove critical in later dealings of the Inner Arbor Trust with the Howard Hughes Corporation.) Phase 2 roughly corresponded to the "performance park" portion of the concept plan, phase 3 to the "curated park" portion, and phase 4 to the future Crescent acreage from Howard Hughes. (The easement agreement was subsequently revised on March 14, 2014, to include a thin strip of land along Little Patuxent Parkway—part of so-called "Lot 9B"—that had been inadvertently left off the original agreement.)

The easement agreement granted the Inner Arbor Trust an extensive set of rights, including rights to construct park features (including taking proposed features through the county planning process), to operate park features and hold park events (and realize revenue from such), and to enter into a broad range of legal agreements with third parties, including agreements supporting integration of the park with Merriweather Post Pavilion.

The Inner Arbor Trust did not immediately acquire that full set of rights for all four easement areas. The Columbia Association granted the full set of specified rights for the Phase 1 easement area upon the signing of the agreement. However granting of full rights outlined in the agreement for the other three easement areas—including in particular the rights to construct and operate new park features—was made contingent on the Trust completing construction of the Chrysalis amphitheater (which the agreement referenced under the name "Treehouse Stage" used in the concept plan) or another designated park feature in the Phase 1 easement area, as well as on other events unique to each phase.

Granting of full rights specified in the agreement for the Phase 2 easement area was also made contingent on "substantial completion" of the pathway system in the Phase 1 easement area, as well as on progression through step 9 of the county planning process (including approval of a Final Development Plan) for a structure in the Phase 2 easement area, as part of the "performance park" portion of the concept plan.

For Phase 3 granting of full rights under the agreement was also made contingent on the Inner Arbor Trust having sufficient funding to create and submit a Final Development Plan for a sculpture garden or botanical garden in the Phase 3 easement area as part of the "curated park" portion of the concept plan. Finally, granting of full rights for the Phase 4 easement area was also made contingent on the actual transfer of the Phase 4 acreage from Howard Hughes to the Columbia Association.

Although the phases were numbered sequentially, Phases 2 through 4 were in fact made independent of each other: Once the Inner Arbor Trust had completed the Chrysalis or other designated park feature in the Phase 1 easement area, granting the Trust the full rights specified in the agreement in any other easement area was dependent only on the requirement(s) for that particular area. (Thus, for example, the Trust could acquire full rights under the easement agreement for the open space transferred to the Columbia Association by the Howard Hughes Corporation prior to any work being done on the "performance park" or "curated park" portions of the concept plan.)

Permitted uses under the easement agreement were specified as those for "arts, cultural and civic purposes as broadly illustrated by the Concept Plan", including performances, arts and cultural attractions, sculpture and art installations, gardens, various park features (including picnic areas and fountains), construction and operation of buildings to support the permitted uses, food and beverage sales, and temporary retail operations (e.g., for festivals).

The first Howard County grant agreement

Finally, on December 18 the Inner Arbor Trust entered into a grant agreement with Howard County under which the county agreed to provide funding in support of the design and construction of the Chrysalis amphitheater, as previously approved by the County Council in May. The first grant under this agreement was in the sum of $300,000, and supplemented the $1.6 million of committed CA funding. (In fulfillment of this commitment CA made a second payment of $450,000 prior to January 31, 2014.)

2014: Planning

The main theme of 2014 was the steady progression of the Inner Arbor plan through the Howard County planning process over organized opposition, including from some Columbia Association board members. For the Inner Arbor Trust this was in fact a race against time to meet key deadlines in the perpetual easement agreement signed with CA the previous December.

Deadlines for the Inner Arbor Trust

The first deadline met was actually the one that was furthest in the future, namely the achievement of 501(c)(3) tax-exempt status. The easement agreement required this to be done by June 30, 2015, but it was actually accomplished on January 31, 2014, just over a month after the signing of the agreement. This was the first step in enabling the Inner Arbor Trust to more actively raise funds from donors for whom the tax deductibility of donations was important. (Under Maryland law the Trust could not actively solicit donations until it was certified by the state. This did not occur until October 22 later that year.)

However the easement agreement with the Columbia Association also required the Inner Arbor Trust to submit a Site Development Plan for the "Phase 1 easement area" (the northern section of Symphony Woods) by April 30, 2014, and to obtain county approval for that plan by November 30 of the same year. If it failed to meet one of these deadlines then the Trust would have to go back to CA to obtain an extension. If it could not obtain an extension then the Trust would risk being deemed in violation of the easement agreement.

Review by the Design Advisory Panel

The Inner Arbor Trust started the formal planning process on February 4, 2014 when it submitted a complete Inner Arbor design to the county for consideration by the Howard County Design Advisory Panel.6 This design formalized the park design presented the previous December and addressed the recommendations made by the Planning Board in its approval of the Final Development Plan previously submitted by the Columbia Association (FDP-DC-MSW-1).

The design as submitted contained two relatively minor revisions to the plan presented in December. The first was the addition of the Merriground, a play area for children. Such a play area was originally envisioned in the Final Development Plan, and in the first Inner Arbor plan was in the form of a "play maze" located across Little Patuxent Parkway relatively close to the entrance drive to The Mall in Columbia. The Merriground replaced this concept with a more "sculptural" set of features located further to the east of the northern section of Symphony Woods, in the location of the "iconic sculpture" originally envisioned by the Inner Arbor concept plan.

The other new feature was the Merriweather Horns, a set of sound sculptures designed by local artist William Cochran for the four proposed park entrances and along the park's pathways. The Merriweather Horns replaced the Word Art and Letter Garden features in the plan presented in December, and were proposed as the public art component of the park as envisioned in the Final Developmemt Plan.

On February 26 Michael McCall of the Inner Arbor Trust and various members of the design team took the Howard County Design Advisory Panel through a 236-slide presentation covering all aspects of the park and the proposed park features. The presentation went very well: The Design Advisory Panel voted unanimously in favor of the plan, raising only a relatively minor concern about the width of some of the pathways, and individual panel members were enthusiastic in their praise of the plan.

Opposition on the CA board

Meanwhile, as the Inner Arbor Trust prepared for the next step in the planning process opponents of the Inner Arbor plan stepped up their activities. During the previous year the changed composition of the Columbia Association Board of Directors had had relatively little effect on its relations with the Inner Arbor Trust. (The CA board had limited itself mainly to consideration of the easement negotiated with the Inner Arbor Trust, and a revision of the CA conflict of interest policy to clarify that it did not preclude CA board members from serving on the board of the Inner Arbor Trust.)

That period of relative quiet ended in the spring of 2014. The first issue to gain traction related to the name of the park: In its submissions to the county planning process the Inner Arbor Trust used the new name "Merriweather Park" (instead of the previous "Symphony Woods Park") to emphasize the integration with Merriweather Post Pavilion and leverage public recognition of the "Merriweather̦" name.

Various members of the Columbia Association Board of Directors objected to the Inner Arbor Trust dropping the use of "Symphony Woods", and on March 13 the CA board voted unanimously to formally request of the Inner Arbor Trust that the name "Symphony Woods" be retained. Later that spring the Inner Arbor Trust attempted to address this controversy by renaming the project "Merriweather Park at Symphony Woods" (similar to the strategy the Baltimore Orioles followed in naming their new stadium "Orioles Park at Camden Yards").

More serious in its implications for the Inner Arbor project was the April 26 election of the Columbia Association Board of Directors. As they were in 2013, opponents of the Inner Arbor plan were successful in electing new CA board members in another relatively low turnout election.7 Plan opponents Jeanne Ketley and Alan Klein won in contested elections against incumbent board member Suzanne Waller and new candidate Bob Fontaine (both plan supporters). Plan opponent Alex Hekimian announced his intent not to run just prior to the filing deadline and was replaced by Reg Avery, who was allegedly recruited by Hekimian and ran unopposed.

Although he was a supporter of the Inner Arbor plan, re-elected incumbent Gregg Schwind, one of the Columbia Association's representatives on the Inner Arbor Trust Board of Directors, expressed concern about public reception of the plan and indicated his willingness to consider "reworking" it. Finally, just prior to the election the CA board finally replaced Ed Coleman (defeated the previous year in the CA board election) as one of the CA representatives on the Trust board, in a 6-3 vote selecting Nancy McCord (who was relatively neutral in her public statements on the Inner Arbor plan) over Inner Arbor supporter Michael Cornell.

Meeting the SDP deadline

In the midst of all this controversy the Inner Arbor Trust met a second key deadline, as it submitted a 83-sheet Site Development Plan (SDP-14-073) to the Howard County Department of Planning and Zoning on April 28, only two days before the April 30 deadline set by the easement agreement with the Columbia Association.

More Howard County funding for the Inner Arbor project

In further good news for the Inner Arbor Trust, Howard County continued its financial support of the Inner Arbor project, with the County Council on May 21 appropriating an additional $1.5 million for Chrysalis construction and related activities in the county's FY15 budget (Council Bill 24-2014), as requested by County Executive Ken Ulman. (The $1.5 million was in the form of a challenge grant requiring the Trust to provide matching funds, although at the time the Trust was not yet authorized to solicit donations.)

The CA board's endorsement of the Inner Arbor plan

However opposition to the Inner Arbor project from some Columbia Association board members continued. The primary strategy by which Inner Arbor opponents pursued their goal was a claim that the Trust had violated the terms of the previously-negotiated easement agreement for Symphony Woods by making "material changes" to the Inner Arbor concept plan.8 After discussing the easement issue in public meetings on May 27 and 28, in its June 12 meeting the Columbia Association Board of Directors narrowly approved by a 5-4 vote a last-minute agenda change to formally consider whether an easement violation had occurred. However the actual motion to hold the Inner Arbor Trust in violation failed on a 3-7 vote, with only Reg Avery, Alan Klein, and Russ Swatek voting in favor.

One question raised in connection with the easement controversy was whether or not the Columbia Association needed to, or at least should, formally approve the Inner Arbor plan in its current form (i.e., beyond the concept plan referenced in the easement agreement). At the July 10 CA board meeting the board considered this question, with Michael McCall of the Inner Arbor Trust present to answer questions posed by the CA board. After discussion the CA board voted 6-4 to endorse the Inner Arbor plan as submitted in the Site Development Plan, with Nancy McCord joining previous Inner Arbor supporters Michael Cornell, Brian Dunn, Tom O'Connor, Andy Stack, and Gregg Schwind in the majority, and Reg Avery, Jeanne Ketley, Alan Klein, and Russ Swatek on the losing side of the vote.

Meanwhile the Columbia Association had completed its original commitment to fund the Inner Arbor Trust: CA paid the Trust an additional $510,000 in the spring of 2014, for a total of $1,410,000 up to that point. The final $190,000 came from what was left of the $250,000 grant that the state of Maryland had made to CA for the original Symphony Woods Park project. ($60,000 of that money had already spent on design work for that project.) On June 18 the state approved CA reassigning the remaining $190,000 to the Inner Arbor Trust.

After the July 10 endorsement of Inner Arbor project by the Columbia Association Board of Directors the CA board transitioned into a role of providing oversight of the Inner Arbor Trust, for example through joint board meetings with the Trust on October 8 and subsequent dates. CA did not commit any further funding to the Inner Arbor Trust once the original $1.6 million commitment was satisfied.9

Review by the Planning Board

Instead the focus shifted again to the Howard County planning process, as the Inner Arbor Trust went before the Planning Board10 in November 2014 to request approval of SDP-14-073, the Site Development Plan for Merriweather Park at Symphony Woods, with the clock ticking toward the November 30 deadline specified in the easement agreement with the Columbia Association.

The Planning Board first held a meeting to consider the Site Development Plan on November 6 but held off making a decision that night. Partly this was to allow more time for the many people who wanted to testify for and against the plan. In the end over forty people spoke about the plan, with opponents outnumbered 2-1 by supporters, who included new Columbia Association President and CEO Milton Matthews (who had replaced Phil Nelson in June) and Howard County Council Chair Mary Kay Sigaty (who referred to the plan as "an exceptional design" and urged the Planning Board to "vote it with enthusiasm"). Many others submitted written testimony, with County Council members Calvin Ball, Greg Fox, and Jen Terrasa writing in support of the plan along with Council member-elect Jon Weinstein.

The Planning Board also held up its deliberations to address concerns raised by the Howard County Citizens Association about allowing adequate time after publication of the Department of Planning and Zoning Technical Staff Report on SDP-14-073. Final consideration was postponed to two weeks later, for the last meeting of the Planning Board in November.

At the November 20 meeting, only ten days before the easement agreement's deadline, the Planning Board rendered its decision, voting unanimously to approve the Site Development Plan. As requested by the Inner Arbor Trust the Planning Board's decision encompassed not only the first two phases of park development, namely constructing the Chrysalis amphitheater and a pathway system, but the remaining five phases as well, including all other park features proposed in the revised Inner Arbor plan for the northern part of Symphony Woods. Phases 1 and 2 were approved without further conditions, while phases 3-7 were approved subject to further review and approval of final design details by the Department of Planning and Zoning and the Planning Board prior to beginning construction.

Speaking about his own decision, Planning Board Chair Josh Tzuker thanked Inner Arbor opponents Cy Paumier, Barbara Russell, and others for their roles in the creation of the community of Columbia—"probably the second most influential thing in my life [after my parents]"—but noted that "We're on a precipice. … It's time for something new and fresh." In comparing Columbia to other Washington-Baltimore suburban communities "competing to create a cosmopolitan cultural center", Tzuker noted that "We have Merriweather—that's what sets us apart. … Merriweather is going to be this cultural touchstone that I think will bring people to Columbia." He concluded by stating that the Site Development Plan submitted by the Inner Arbor Trust met the Planning Board's criteria for Merriweather-Symphony Woods development, and that the board set the criteria the way it did because it wanted to promote a "holistic" vision of downtown Columbia—"the vision we all wanted to see".

The county's approval of the Site Development Plan meant that the Inner Arbor Trust had met all three of the key deadlines in the easement agreement with the Columbia Association. The Trust thus ended 2014 free to move forward with the project of developing Symphony Woods according to the Inner Arbor plan.

2015: Building

With the Howard County Planning Board having approved the Site Development Plan for Merriweather Park at Symphony Woods, in 2015 the Inner Arbor Trust began the work of realizing that plan, both in terms of building the actual foundation for the Chrysalis amphitheater and also in terms of strengthening the organizational foundation for the Trust moving forward. A great deal of that work involved solidifying the Inner Arbor Trust's relationships with the other entities involved in Merriweather-Symphony Woods development, in pursuit of tighter integration between the Symphony Woods and Merriweather Post Pavilion properties.

The I.M.A. agreement

On March 6, 2015, the Inner Arbor Trust entered into a long-term agreement with It's My Amphitheater, Inc., the operators of Merriweather Post Pavilion. This agreement provided for an ongoing stream of payments from I.M.A. to the Trust for the use of Symphony Woods for Merriweather Post Pavilion events, amounting to a total of $1.7 million in Trust revenue for the first ten years of the agreement. (This $1.7 million was counted by Howard County as satisfying the matching requirement associated with the $1.5 million grant in 2014.) The agreement also provided for the use of public areas of the Merriweather Post Pavilion by park visitors during times when no events were being held there, in line with the theme of "operational elasticity" promoted by Michael McCall in his original Inner Arbor presentations.

On April 15 the Inner Arbor Trust Board of Directors assumed its present form as Dave Sciamarelli was elected to replace Paul Monteiro, who had in turn succeeded original board member Beverly White-Seals. The next-newest board member, Karen Newell, had previously been elected on August 7, 2014, to replace Deborah Ellinghaus. This left Gregg Schwind and Gill Wylie as the longest-serving Inner Arbor Trust board members, both having been on the board since the first board meeting on May 10, 2013.

Meanwhile on April 25 the Columbia Association again held an election for its Board of Directors. While still present, the controversies over the Inner Arbor plan were more muted in this election than in prior ones. Inner Arbor opponent Dick Boulton replaced supporter Tom O'Connor, Inner Arbor supporter Ed Coleman (running for an open seat) was defeated by Janet Evans, and Dr. Chao Wu replaced Inner Arbor supporter Michael Cornell, who did not run again. On May 14 the CA board selected Dick Boulton to replace Nancy McCord as one of CA's representatives on the Inner Arbor Trust, with Gregg Schwind again selected for that role as well.

Continuation of Howard County funding

In May Howard County continued its financial support of the Inner Arbor Trust, as County Executive Alan Kittleman proposed, and the Howard County Council approved, $1.395 million of additional funding for the Trust as part of the FY16 budget. (The relevant legislation, Council Bill 23-2015, was introduced May 4, approved May 22, and signed into law June 1.) With this additional funding the county increased its support of Merriweather Park at Symphony Woods and the Chrysalis amphitheater to a total of $6.395 million, almost four times the funding contributed by the Columbia Association. (The relevant grant agreement was signed later that year on September 18, the third consecutive agreement between Howard County and the Inner Arbor Trust.)

The Howard Hughes agreements

On May 27, 2015, the Inner Arbor Trust continued its activities relating to integration with Merriweather Post Pavilion by entering into a reciprocal easement agreement with Howard Hughes Corporation subsidiaries Merriweather Post Business Trust and Howard Research and Development. This agreement provided for the Trust and Howard Hughes to coordinate activities relating to development of land and facilities intended for joint use between Merriweather Post Pavilion and Merriweather Park at Symphony Woods, as envisioned by the downtown Columbia plan and the design guidelines for the Merriweather-Symphony Woods neighborhood.

(This agreement was made possible only because the Trust already had an easement from the Columbia Association for the land adjacent to Merriweather Post Pavilion on which the joint uses would occur. That adjacent acreage had been included in the Phase 1 easement area in the Trust's previous easement agreement with CA.)

The next day, May 28, the Inner Arbor Trust appointed Nina Basu as its first General Counsel—a reflection of the increasing number of legal agreements the Trust was entering into and the increased amount of legal activity associated with the upcoming park construction and related activities. The Trust also appointed a new Treasurer, Kirsten Coombs. (Coombs replaced previous Treasurer Noreen Qureshi, who in turn had replaced Rafia Siddiqui, the Trust's original Treasurer.)

On September 1 the Inner Arbor Trust entered into a trademark license agreement with Howard Hughes Corporation subsidiary Merriweather Post Business Trust. This agreement allowed the Trust the perpetual royalty-free use of the word mark "Merriweather" in connection with the naming and marketing of Merriweather Park at Symphony Woods. The Trust could thus leverage not only the existing broad public recognition of the Merriweather name, but also future marketing efforts by Howard Hughes in support of its own development activities in what it had taken to calling the "Merriweather District".

Further integration with Merriweather Post Pavilion

On September 3, 2015, the Howard County Planning Board unanimously approved a new Final Development Plan, FDP-DC-MSW-1A, a revision of the Final Development Plan FDP-DC-MSW-1 originally submitted by the Columbia Association for Symphony Woods Park. While FDP-DC-MSW-1 covered only a 16-acre portion of Symphony Woods (the "public park" envisioned in the Inner Arbor concept plan), FDP-DC-MSW-1A covered a total of 35 acres including the entire Merriweather Post Pavilion property as well as additional portions of Symphony Woods comprising the "performance park" of the Inner Arbor concept plan. (The concept plan's "curated park" in southern Symphony Woods—the proposed location for a sculpture garden—was not addressed by FDP-DC-MSW-1A.)

Specific changes in FDP-DC-MSW-1A included an increase in the height limit for the Merriweather Post Pavilion stagehouse, provision of ADA-compliant parking spaces, and a shared-use restroom in Symphony Woods. However FDP-DC-MSW-1A was equally significant for marking a new level of formal coordination in Merriweather-Symphony Woods planning among the various parties responsible for the properties, and even tighter integration between Merriweather Post Pavilion renovation projects and the development of Merriweather Park at Symphony Woods. (FDP-DC-MSW-1A was followed up in December by SDP-16-018, a Site Development Plan for renovations to both properties.) Finally, FDP-DC-MSW-1A replaced the original CA-submitted Final Development Plan (FDP-DC-MSW-1) and eliminated any lingering consistencies between that plan and the subsequent Site Development Plan SDP-14-073 approved by the Planning Board.

Together these and other relationships among the various organizations involved in downtown Columbia development formed the basis for a new identity for downtown, with Merriweather Post Pavilion at the center, Merriweather Park at Symphony Woods surrounding it, and both within a newly-named Merriweather District combining the Merriweather-Symphony Woods and Crescent neighborhoods—all within the context of the broader Columbia planned community.

Breaking ground on the Chrysalis

This heightened level of cooperation was celebrated on September 12, 2015, at the groundbreaking ceremony for the Chrysalis amphitheater, which featured representation from all the major players involved in the creation of Merriweather Park at Symphony Woods, including the Inner Arbor Trust, the Columbia Association, Howard County Executive Alan Kittleman and members of the Howard County Council, the Howard Hughes Corporation, I.M.A., the Downtown Columbia Arts and Culture Commission, and the state of Maryland.

Also represented was the Columbia Festival of the Arts, whose executive director Todd Olson publicly announced the festival's intent to host future performances at the Chrysalis amphitheater when completed—moving from the previous venue at the lakefront, Columbia's traditional downtown, to the heart of Columbia's future downtown. Finally, the ceremony featured participation by the Howard County Public School System, in the form of a student team from Oakland Mills High School that used the Minecraft world-building software to create a virtual model of the Chrysalis amphitheater and other planned features in Merriweather Park at Symphony Woods.

The beginning of Chrysalis construction

The months after the groundbreaking saw the plans for Merriweather Park at Symphony Woods started to be realized, as Whiting-Turner (the construction contractor selected by the Inner Arbor Trust) began the work of preparing the Chrysalis site. Appropriately enough, given the past controversies over tree preservation in Symphony Woods, Whiting-Turner's first task was to carefully prune tree roots in areas to be excavated and place mats to protect critical root zones. Subsequent weeks saw the laying of water lines, construction of an underground cistern to control storm water runoff, and the beginnings of the foundation for the Chrysalis amphitheater.

As 2015 ended the visible evidence of the Chrysalis amphitheater's presence was still below ground. 2016 will see the Chrysalis rise above the surface of Symphony Woods. Future articles in this series will describe the people and organizations bringing the Chrysalis to life and how their work will contribute to the final structure and the park surrounding it.

Diagram of the legal agreements and other relationships among the various organizations involved in development of Merriweather Post Pavilion, Merriweather Park at Symphony Woods, and the overall Merriweather District (combining the Merriweather-Symphony Woods and Crescent neighborhoods). Items in red were not finalized as of the end of 2015; in particular the Inner Arbor Trust had received building permits for grading the Chrysalis site and for constructing its foundation, but had not yet received a third permit for the Chrysalis structure itself. Click for a higher-resolution version. Image © 2015 Inner Arbor Trust; used with permission.

For further exploration

This article is based on material from a variety of online sources, including the following:

Newspaper articles from the Baltimore Sun online archives for 2013, 2014, and 2015, including the following:

"CA board approves concept plan for Symphony Woods" (February 15, 2013)

"Details of Symphony Woods arts park revealed" (December 1, 2013)

"Inner Arbor plans 'wow' Howard design panel" (February 27, 2014)

"CA board endorses plans for Symphony Woods" (July 11, 2014)

"Howard Planning Board gives green light to Inner Arbor" (November 20, 2014)

"Downtown Columbia celebrates Chrysalis groundbreaking in Symphony Woods" (September 14, 2015)

Newspaper articles from the Columbia Flier online archives

Various Inner Arbor Trust documents, including the following:

IAT-CA easement (amended to include Lot 9B) [PDF] (March 14, 2014)

Letter to Hickory Ridge Village Manager Jessamine Duvall [PDF] (May 27, 2014) (summarizes history of the Inner Arbor Trust up to that time)

A Brief History of the Inner Arbor Trust [PDF] (October 2015)

Various Howard County planning and legislative documents:

Downtown Columbia Plan: A General Plan Amendment [PDF] (February 1, 2010)

Land Development Review Process for Downtown Columbia Revitalization [PDF] (November 2010) (Outlines the 16-step county planning and zoning process applicable to the Merriweather-Symphony Woods Neighborhood)

Howard County Planning Board Decision and Order, Case No. PB 394 [PDF] (September 6, 2012) (Planning Board recommendations for changes to Symphony Woods Park plan, FDP-DC-MSW-1)

DPZ Technical Staff Report on SDP-14-073 [PDF] (October 30, 2014)

Planning Board decision on SDP-14-073 [PDF] (November 20, 2014) (Approval of Site Development Plan for Merriweather Park at Symphony Woods)

DPZ Technical Staff Report on FDP-MSW-1A [PDF] (August 20, 2015)

DPZ Technical Staff Report on SDP-16-018 [PDF] (December 3, 2015)

Council Bill 25-2013 (May 2013) ($3.5 million appropriation for Chrysalis design and construction)

Council Bill 24-2014 (May 2014) ($1.5 million appropriation for the Inner Arbor Trust along with a requirement for the Trust to provide matching funds)

Council Bill 23-2015 (May 2015) ($1.395 million appropriation for the Inner Arbor Trust)

Various Columbia Association documents, including in particular the following with specific materials as noted:

FDP-DC-MSW-1, "Downtown Columbia Merriweather-Symphony Woods Neighborhood Final Development Plan" [PDF] (the original Symphony Woods Park plan as submitted to Howard County)

Board agenda for August 23, 2012 [PDF] (Jan Clark memo re Howard Hughes Corporation plans and their impact on CA)

Board agenda for October 11, 2012 [PDF] (Phil Nelson memo of October 5, 2012)

Board minutes for October 11, 2012 [PDF] (Phil Nelson presentation and straw polls)

Board minutes for January 24, 2013 [PDF] (Michael McCall presentation on the Inner Arbor concept plan)

Board agenda for February 14, 2013 [PDF] (Phil Nelson memo of February 7, 2013, "Formation of a Trust for Symphony Woods Development")

"Formation of a Trust for Symphony Woods Development" [PDF] (Phil Nelson memo of February 13, 2013, updating the February 7 memo)

Board minutes for February 14, 2013 [PDF] (Approval of Inner Arbor concept plan, creation of independent 501(c)(3) organization, granting of easement)

Board minutes and related material for April 25, 2013 [PDF] (Discussion of the need to maintain an "arms-length distance" between CA and the Inner Arbor Trust)

Board work session on May 28, 2014 [PDF] (Appearance by Michael McCall and Inner Arbor Trust board members to discuss the project and questions concerning it)

Board minutes for June 12, 2014 [PDF] (Vote on whether the Inner Arbor Trust had violated the easement on Symphony Woods)

Board minutes for July 10, 2014 [PDF] (Vote on CA endorsement of the Inner Arbor plan)

Board Operations Committee agenda for November 14, 2015 [PDF] (Sheri Faranoff memo discussing guidelines for CA board members serving on the Inner Arbor Trust board)

Various local blogs and blog posts, including in particular:

HocoRising (Tom Coale)

"Symphony Woods" (January 22, 2013)

"CA Board Recap: January 24, 2013 Board of Directors Meeting" (January 25, 2013)

Dr Chao Wu

"Background on CA and Inner Arbor Trust" (October 7, 2015) (Re-post of an article "Background on CA Board & Inner Arbor" by Andy Stack, dated September 15, 2015)

For more of my opinions on and explanations of various aspects of the Chrysalis and Merriweather Park at Symphony Woods, see the Inner Arbor-related posts in the series "The Inner Arbor plan takes shape" and elsewhere on this blog. (Note that some of these posts contain outdated information relating to park features that were later dropped or revised.)

The Howard County Planning Board was established to "make recommendations to the County Council and the Zoning Board on all matters relating to: The Planning and Zoning of the County, the adoption and amendment of regulations regarding the Planning and Zoning of the County, and amendments to the zoning map or zoning regulations." (See Sec. 16.900 of the Howard County Code of Ordinances.) As of September 2012 the members of the Planning Board were Jacqueline Easley, Dave Grabowski, Bill Santos, Josh Tzuker, and Paul Yelder. ↩

For example, an August 17, 2012, memo from Columbia Association staff member Jan Clark to the CA board noted of the plan proposed by Howard Hughes that "This concept (a.k.a., the 'McCall Plan') has the support of most community leaders …" ↩

The term "Trust" referenced in Nelson's recommendations, and later in the name "Inner Arbor Trust", was used in the same sense as with respect to organizations like the Pittsburgh Cultural Trust, the Hudson River Park Trust, and the Trust for the National Mall: to denote a nonprofit organization with 501(c)(3) tax-exempt status chartered to develop, enhance, and/or maintain properties held by others. ↩

For various reasons only a subset of Columbia residents are eligible to vote in CA elections, and only a small subset of those bother to do so. For example, in the 2013 elections Nancy McCord defeated Regina Clay by a margin of 12 votes with a total turnout of 362 people. ↩

The Columbia Association adopted a similar strategy in setting up an independent nonprofit organization, Columbia 50th Birthday Celebration, Inc., to coordinate activities relating to the 50th anniversary of the founding of Columbia. ↩

The Design Advisory Panel was created by Howard County in 2008 to (among other things) "Provide expert advice for Downtown Columbia Revitalization to … the Planning Board regarding the consistency of the site development plans submitted for approval in the Downtown Columbia Revitalization process to the neighborhood design guidelines." (See Sec. 16.1500 of the Howard County Code of Ordinances.) Its members are required to be "professional[s] in architecture, civil engineering, landscape architecture, urban planning, or a related field." As of February 2014 the members of the Design Advisory Panel were Hank Alinger, Phyllis Cook, Mohammad Saleem, Phil Engelke, Rob Hollis, Don Taylor, and Peggy White. Of these all but Engelke and Saleem were present at the meeting at which the Merriweather Park SDP was reviewed and unanimously endorsed. ↩

In the closest of the 2014 elections (in which Alan Klein defeated Bob Fontaine) the outcome was decided by a margin of 17 votes with a total turnout of 375 people. ↩

To be more specific, the claim that "material changes" were made rested primarily on the distinction between the original Inner Arbor concept plan, included as an attachment to the easement agreement, and the Site Development Plan submitted to Howard County, which reflected the elaboration of the concept plan in accordance with the Final Development Plan previously submitted by CA. ↩

The Columbia Association's decision to no longer fund the Inner Arbor project also resulted in CA having a decreased ability to oversee the project or impose its own conditions on the project tied to CA funding. For example, the original grant agreement between CA and the Trust required the Trust to provide quarterly financial reports to CA; that obligation went away once the grant agreement ended. ↩

As of November 2014 the members of the Planning Board were Jacqueline Easley, Phil Engelke, Erica Roberts, Bill Santos, and Josh Tzuker. ↩

Frank firstname.lastname@example.com discuss the various institutional activities related to implementation of the Inner Arbor planCreating the Chrysalis: Vision and strategy2015-11-01T13:00:00-05:002015-11-01T13:00:00-05:00https://civilityandtruth.com/2015/11/01/creating-the-chrysalis-vision-and-strategy

Site plan for Merriweather Park at Symphony Woods, as presented to the Howard County Design Advisory Panel on February 26, 2014. The Chrysalis amphitheater is in the lower right. Click for a higher-resolution version. Image © 2014 Inner Arbor Trust; used with permission.

tl;dr: I explore the vision for a new park in Symphony Woods and the strategy to implement it.

This article is one in a series exploring in depth the creation of the Chrysalis amphitheater in Merriweather Park at Symphony Woods in Columbia, Maryland. For the complete list of articles please see the introduction to the series.

The previous article in this series recounted the history of Symphony Woods up to the fall of 2012. At that time the Columbia Association Board of Directors, at the suggestion of CA staff, decided to re-evaluate its plans for creating a park in Symphony Woods. That process ultimately led to CA's adopting a new approach, dubbed the Inner Arbor plan, and creating a new organization, the Inner Arbor Trust, to implement that plan. This article describes the vision motivating the plan and the strategy to implement that vision as it was created and refined by Michael McCall, now President and CEO of the Inner Arbor Trust.

The roots of the Inner Arbor plan

Meetings of the Columbia Association Board of Directors feature a "Resident Speak Out" period during which Columbia residents and other users of CA services can briefly address the CA board on topics relevant to the Columbia Association. On September 22, 2011, one of the people speaking during the board meeting was Columbia resident Michael McCall.

McCall spoke of reading newspaper articles about the Design Advisory Panel meeting on the Symphony Woods Park Final Development Plan, and noted his agreement with the panel members' concerns: "There's not a vision for the whole park—not just the front that faces Little Patuxent [Parkway], but the entire 'doughnut', … the whole thing." He went on to note, "We have to start with the end in mind: What do we want Symphony Woods to be twenty years from now? What is its strategic purpose? What is the guest experience? What is it that we want, what is it we aspire to?"

Columbia Association board member Suzanne Waller, alluding to the draft Symphony Woods Park vision statement that the board was considering (and would adopt at the next board meeting), responded that "in fact we do have a vision". McCall replied, "That's wonderful. However [in] the plans that I could download … and an RFP for a fountain, I did not see or hear or read or feel a vision, …. A fountain is a tactic, and I'm looking for the strategy."

Although it went mostly unremarked at the time, McCall's appearance at the Columbia Association Board of Directors meeting that night marked the beginning of a major shift on the part of the CA board, a shift that ultimately resulted in CA's adoption of the Inner Arbor plan, the creation of the Inner Arbor Trust, and the beginnings of Merriweather Park at Symphony Woods.

How did Michael McCall come to be involved with Symphony Woods? Originally from Rochester, Minnesota, in 1982 McCall moved to Columbia to join the Enterprise Development Company, the for-profit arm of the Enterprise Foundation (now Enterprise Community Partners), a non-profit organization created by Jim Rouse and his wife Patty in 1981 to help develop affordable housing in the US. After working on several Enterprise Development projects, including a "stealth" joint venture with the Walt Disney Company, in 1992 McCall started Strategic Leisure, Inc., a consulting firm working on development projects in the US and overseas.

Although he had lived in Columbia for thirty years, McCall had been relatively uninvolved in Columbia and Columbia Association affairs. As he noted in his Resident Speak Out comments, "I've never focused on where I live, because when you're dealing with the Corps of Engineers in Tennessee [for a project in Pigeon Forge] you just kind of want to relax when you're home." Thus the perception of McCall by some that he was an outsider as far as Columbia downtown planning was concerned, not a true heir to the vision that Jim Rouse had for the community.

However a more accurate way to put it is that McCall, with his catchy slogans and talk of the "guest experience", simply represented another aspect of Jim Rouse's legacy—not just Rouse the earnest liberal reformer concerned with diversity and social justice, but also Rouse the enthusiastic developer who once claimed that "the greatest piece of urban design in the United States today is Disneyland".

Prompted by the Design Advisory Panel's verdict on the existing plan for Symphony Woods, McCall decided to take a look at the problem himself. After two decades of unsuccessful attempts to enhance Symphony Woods and almost a decade of community in-fighting over downtown Columbia development, McCall brought a different but still Rouse-like perspective on the problem, and circumstances were such that others were willing to consider that perspective and enter into conversations with him about the future of Symphony Woods.

The result of those conversations was a concept plan for what McCall called the "Inner Arbor" project—a punning name by which he sought to emphasize that the development of Merriweather-Symphony Woods, together with the simultaneous development of the Crescent property, could have as positive an impact on downtown Columbia as the Inner Harbor festival marketplace and associated developments had on downtown Baltimore.1 The Inner Arbor plan embodied both a vision and (over time) an increasingly more detailed strategy for enhancing Symphony Woods in the context of the overall Merriweather-Symphony Woods neighorhood.

A comparison of the Tivoli Garden and Millennium Park sites (outlined in yellow) to the Merriweather-Symphony Woods neighborhood (outlined in red), as presented to the Howard County Design Advisory Panel. Click for a higher-resolution version. Image © 2014 Inner Arbor Trust; used with permission.

A vision in words and pictures

Contrasting a vision statement with a mission statement, local blogger James Howard noted, "The mission statement tells what we are doing. The vision statement tells why we are doing it. It [is] finishing the sentence that begins, 'We imagine a world where …'"

The canonical vision for Merriweather-Symphony Woods is from the Downtown Columbia Plan. That vision can be re-expressed in Howard's phrasing as follows: "We imagine a world where Merriweather-Symphony Woods is a new kind of cultural park, where the landscape becomes a setting for arts, cultural and civic uses."

This is brief and to the point—something recommended for vision statements—and also reflects the community consensus on the future of the Merriweather-Symphony Woods neighborhood that was forged through the Howard County planning and legislative processes. It is the vision that informed the initial Inner Arbor concept plan presented by Michael McCall, and continues to inform the work of the Inner Arbor Trust to create Merriweather Park at Symphony Woods.

However this vision statement in and of itself is not as emotionally resonant as it might be. It works well in the context of a planning document, but less well as a vision to excite people. In contrast to Antoine de Saint-Exupéry's advice on building a ship, it is more about collecting wood and assigning tasks and less about getting people to "long for the endless immensity of the sea".

The Inner Arbor concept plan remedied this lack not by trying to rewrite the "official" Merriweather-Symphony Woods vision statement, but rather by using images and analogies to supplement it and make it more vivid. In particular, one key question addressed in the concept plan presentation is the following: If you wanted to create a "new kind of cultural park" for "arts, cultural, and civic uses", and you had 45 acres of land to work with (the combined area of Symphony Woods and Merriweather Post Pavilion), what kind of park could you create?

The answer given by the concept plan presentation was that you could create something like Tivoli Gardens in Copenhagen (20 acres), or Millennium Park in Chicago (25 acres)—and the presentation then went on to elaborate on that answer by showing several pictures of what Tivoli Gardens and Millienium Park actually look like to visitors. This made the Merriweather-Symphony Woods vision more visceral and appealing: If the pictures were translated into words then those words might be, "We imagine a world where Merriweather-Symphony Woods is to Columbia what Tivoli Gardens is to Copenhagen, or Millennium Park to Chicago."

Re-expressing the Merriweather-Symphony Woods vision in these terms has several implications for what the Merriweather-Symphony Woods neighborhood might be, indeed what it must be in order for the vision to be realized:

The world we imagine in the vision for Merriweather-Symphony Woods is one where

… Merriweather-Symphony Woods is loved by Columbia and Howard County residents in the same way that Tivoli Gardens and Millennium Park are loved by residents of Copenhagen and Chicago—the sort of place you might go to meet your friends even if you don't have definite plans, just because it's a great place to be.

… Merriweather-Symphony Woods is known by people well outside the area—the sort of place where if you're in town and able to go there you take a selfie of yourself and your friends, because you want other people to know you've been there.

… Merriweather-Symphony Woods has something–whether one thing or a combination of things–that can't be found anywhere else.

Looking at the Merriweather-Symphony Woods vision statement in this alternative formulation also has implications for the strategy discussed in the next section:

First, realizing the Merriweather-Symphony Woods vision will be a long-term effort. For example, Tivoli Gardens has been the beneficiary of over 170 years of evolution. It shouldn't take 170 years to fully realize the vision for Merriweather-Symphony Woods, but it certainly will take more than two or three years.

Second, realizing this vision will require an intensive design effort. Some people have looked at Symphony Woods simply as an exercise in preservation—that at the extreme it's simply a matter of not cutting trees down or otherwise disturbing the woods. But the comparison to Tivoli Gardens and Millennium Park implies that preservation of trees, intelligent restoration of the landscape, and sensitively-designed park structures are all needed—Merriweather-Symphony Woods is too small a site, is in too built-up a setting, and supports too intensive a set of uses for a simple "hands off" strategy to work.

Finally, realizing the Merriweather-Symphony Woods vision requires looking outside Columbia to find the best and most appropriate design talents for the task at hand, wherever in the world they might be found.

Is this a realistic vision? The answer implied by the Inner Arbor concept plan presentation is yes, given a reasonable amount of time, money, and design talent. As Michael McCall noted in his Resident Speak Out comments, the key is to have the right strategy.

Inner Arbor concept plan, "concerto in three parks". Click for a higher-resolution version. Image © 2013 Inner Arbor Trust; used with permission.

A strategy for the whole park

The vision of a "new kind of cultural park" that could be the equivalent of Tivoli Gardens or Millennium Park in a Columbia context is a compelling one. What was needed next was a suitable long-term strategy for making that vision a reality. As Michael McCall wrote in a column for the magazine Entertainment Management, "Strategy, like winning, is not everything; it is the only thing that counts until it is right."

In the case of Symphony Woods there was a vision, along with proposed tactics (pathways, a fountain, a café), but no clear strategy. As McCall wrote in the same column concerning the "math of success", "Lacking Strategy + Good Execution = Disappointment." In the case of Symphony Woods the key to creating a good strategy was to not focus on just the section of Symphony Woods covered by the then-current Columbia Association plan, but rather to go up a level and consider the entire Merriweather-Symphony Woods neighborhood—the "whole park", as McCall put it in his Resident Speak Out remarks, the "whole thing".

The strategy embodied in the Inner Arbor concept plan is to treat Merriweather-Symphony Woods as three parks in one, or a "concerto in three parks" in McCall's phrase:

The northern section of Symphony Woods, the 16-acre area covered by the Columbia Association's previously-submitted Final Development Plan, is to be the "public park". This is in line with people's traditional conception of Symphony Woods: It is the part of Symphony Woods most familiar to Columbia and Howard County residents (including as the site of the Wine in the Woods festival), the part previously threatened by the intensive development contemplated in the original GGP draft downtown plan, and the part that the Columbia Association was already focusing on prior to the creation of the Inner Arbor plan.

The combination of Merriweather Post Pavilion and a relatively open adjacent area in the eastern part of Symphony Woods is to be the "performance park". This combined area forms a natural east-west axis south of the public park, with the Symphony Woods portion having been previously considered as the site for a new Columbia Association headquarters, and is potentially suitable for other "arts, cultural and civic uses".

Finally, the southern portion of Symphony Woods, just north of the Crescent property, is to be the "curated park", with a focus on public art. Due to poor public access that area has been even more neglected and unused than the northern section of Symphony Woods. However with the planned build-out of the Crescent property the southern section of Symphony Woods will assume more importance, and arguably will one day be as prominent a gateway into the Merriweather-Symphony Woods neighborhood as the northern section. It also has a small pond to provide a focal point for the area and a backdrop for art works.

The Inner Arbor concept plan also contains a number of suggested ways to realize the "concerto in three parks" strategy: In the performance park, an "arts village" hosting new indoor theatrical venues to replace the existing Toby's Dinner Theatre facility. In the curated park, a sculpture garden with "organic art" to complement the natural landscape. In the public park, an "iconic sculpture" and a "treeline" boardwalk to connect to the performance park. And finally, a bridge to tie Merriweather Post Pavilion and the arts village to a parking structure and transit facility suggested for outside of Symphony Woods on the current Toby's Dinner Theatre site.

"Operational elasticity" and "beyond the berm" strategy as embodied in the proposed boundary area between Merriweather Post Pavilion and Symphony Woods in the Inner Arbor plan. Click for a higher-resolution version. Image © 2014 Inner Arbor Trust; used with permission.

A strategy for the public park

The original Inner Arbor concept plan did not suggest any structures for the section of Symphony Woods just north of Merriweather Post Pavilion and just south of Little Patuxent Parkway. That area was already the subject of Columbia Association planning efforts for Symphony Woods Park, and there was already a set of proposed park features submitted as part of the Final Development Plan previously approved by the Howard County Planning Board. However the Planning Board had called for key changes to the FDP, including in particular rerouting paths to avoid trees and pursuing a closer integration of the park with Merriweather Post Pavilion.

The next step in the evolution of the Inner Arbor plan was to focus on that northern section of Symphony Woods, the section containing the public park envisioned in the Inner Arbor concept plan. This made sense for several reasons:

First, this was the aspect of Symphony Woods development that was furthest along. The Howard County planning process for downtown Columbia requires a total of 16 steps: eight steps for a Final Development Plan, and a further eight steps for a Site Development Plan. As noted in the final slides of the public presentations of the Inner Arbor concept plan, development of the northern public park section of Symphony Woods was already at step 9, having completed FDP review, while development of the performance park and curated park in the eastern and southern sections was at step 1.

Thus the Symphony Woods easement agreement between the Columbia Association and the Inner Arbor Trust prioritized development of the public park over development of the performance park and curated park. (See the next article in the series for more information on this agreement.)

Second, given the concurrent planning for the renovation of Merriweather Post Pavilion, developing a plan for integration of the pavilion property with the northern section of Symphony Woods was a high priority.

Finally, development of the performance park and curated park was and is conditional on the pace of development of the Crescent property surrounding Symphony Woods to the south and east: Public use of the performance park and associated arts village envisioned in the Inner Arbor concept plan assumes implementation of new facilities for public parking outside of Symphony Woods, while public use of the curated park assumes conversion of the existing private Symphony Woods Road south of Symphony Woods into a public street. Both of these developments will take some time to come to fruition.

Given these factors, Michael McCall's chosen next task was to create an improved strategy for the "public park" aspect of the Inner Arbor concept plan, building on the previously-approved Final Development Plan together with the associated recommendations by the Planning Board for meandering paths and integration with Merriweather Post Pavilion.

Achieving better integration with Merriweather Post Pavilion was seemingly the tougher challenge, especially given the traditional practice of enclosing Merriweather Post Pavilion with a fence and entirely closing Symphony Woods during Merriweather events. McCall's refined strategy for the public park in northern Symphony Woods was built on two principles, "operational elasticity" and "beyond the berm":2

First, the Merriweather Post Pavilion property would be treated as an extension of the public park, and be opened to visitors year-round during times when the pavilion did not host ticketed events. In return access control for Merriweather Post Pavilion would be provided by a new boundary feature located in Symphony Woods proper, replacing the current fence at the property line on the north side of the pavilion site. The general public would then be allowed access to the portion of Symphony Woods north of this new boundary even during Merriweather Post Pavilion events.

These actions would open up a transition area on the east-west ridge line between the Symphony Woods and Merriweather Post Pavilion properties, a transition area in which a variety of "arts, cultural and civic uses" could be accomodated. In particular, this area could be used for the "Fountain Plaza" envisioned by the downtown Columbia plan, only located on the pavilion site rather than in Symphony Woods.3

In comparison to integration with Merriweather Post Pavilion, incorporating the "meandering paths" recommendation into the strategy seemed relatively straightforward. At the highest level it mainly required abandoning the relatively rigid cruciform arrangements of paths specified in the Final Development Plan and moving to a curved pathway system that respected the existing trees and the topography in which they were situated.

However in practice this aspect of the public park required significant thought as well, in particular to address the "industrial engineering" aspects discussed by Michael McCall in his original Resident Speak Out comments: Would the pathway system adequately handle circulation for the largest events at Merriweather Post Pavilion, as well as events like Wine in the Woods? How would the pathway system function to draw people into the public park? What park features would be most effective in attracting visitors, and how would the pathways most effectively direct people to those features?

Key features of the Inner Arbor plan for the public park aspect of the Inner Arbor concept plan for Merriweather-Symphony Woods, showing relocation of those features from the locations in the Final Development Plan. Click for a higher-resolution version. Image created by Frank Hecker based on Google Maps satellite imagery, sheet 3 of FDP-DC-MSW-1, "Downtown Columbia Merriweather-Symphony Woods Neighborhood Final Development Plan", and slides 25-33 of the Inner Arbor Trust presentation to the Design Advisory Panel.

Tactics for the public park

As it evolved the Inner Arbor plan for the public park reflected the answers to those questions, answers embodied in the various tactics by which the new park strategy was to be implemented. Michael McCall's approach was to take the list of previously proposed "tactics", i.e., the park features outlined in the approved Final Development Plan, and enlist each of them in the service of this new strategy.

As noted above, the fountain called out in the Final Development plan as being located in Symphony Woods was instead proposed to be relocated on the Merriweather Post Pavilion site as part of the transition area between the pavilion site and the Symphony Woods property.

A new feature not specifically called out in the Final Development Plan was the Caterpillar "green berm" stretching east to west just north of Merriweather Post Pavilion. The Caterpillar's primary function is to provide access control from the northern section of Symphony Woods into the transition area bordering Merriweather Post Pavilion. It serves in place of a traditional fence, like the one presently separating Merriweather Post Pavilion from Symphony Woods, and makes for a much more visually attractive barrier—the "art of bounds", as McCall put it.

The remaining features were relocated from their position in Symphony Woods as called out in the Final Development Plan to new positions elsewhere in Symphony Woods:

The children's activity area, now named the Merriground, was originally proposed to be right next to the Merriweather VIP parking lot. It was moved to a more scenic location further north in the woods. The shared use café, the Butterfly in the Inner Arbor plan, was then moved to the activity area's former location next to the Merriweather VIP parking lot, near the east entrance of Merriweather Post Pavilion, so that its shared use with Merriweather Post Pavilion would be more convenient.

Finally, the proposed shared use amphitheater, what is now to be the Chrysalis, was moved slightly to the east. This took it down a hill somewhat compared to the location in the FDP, providing more space for the audience and more separation from Merriweather Post Pavilion.

The Final Development Plan also referenced public art in the park. That function is fulfilled in the Inner Arbor plan by the Merriweather Horns sound sculptures, which replaced other art features proposed in an earlier iteration of the Inner Arbor plan.

The Inner Arbor plan has thus evolved from the earliest concept plan to the latest site development plan for the northern section. The concept plan of late 2012 and early 2013 provided an overall framework for developing the whole of Symphony Woods as a component of the Merriweather-Symphony Woods neighborhood, the more detailed plan of late 2013 provided a framework for developing the public park component of Merriweather-Symphony Woods, and the revised plan of early 2014 locked down the detailed site design that now drives the development of Merriweather Park at Symphony Woods.

The next article in this series will look at the processes and institutions by which and through which the vision and strategy discussed in this article are being realized in the current construction of the Chrysalis amphitheater.

For further exploration

This article is based on material from a variety of online sources, including the following:

Newspaper articles from the Baltimore Sun online archives, including in particular the following:

"McCall invokes Rouse in design for Symphony Woods Park"

Newspaper articles from the Columbia Flier online archives

The Strategic Leisure web site, including in particular the following article:

"The Strategic Math of Success" [PDF]

Various Inner Arbor Trust documents, including the following:

Michael McCall's presentation of the Inner Arbor concept plan to Leadership Howard County [video] (September 20, 2013)

Inner Arbor Trust presentation to the Howard County Design Advisory Panel [video] (February 26, 2014)

Various Howard County planning documents:

Downtown Columbia Plan: A General Plan Amendment [PDF] (February 1, 2010)

Howard County Design Advisory Panel minutes, July 13, 2011 [PDF]

Howard County Planning Board Decision and Order, Case No. PB 394 [PDF] (September 6, 2012)

Land Development Review Process for Downtown Columbia Revitalization [PDF] (November 2010)

Various Columbia Association documents, including in particular the following:

FDP-DC-MSW-1, "Downtown Columbia Merriweather-Symphony Woods Neighborhood Final Development Plan" [PDF]

Jim Rouse comments on Disneyland

James Howard's blog post on vision statements

Antoine de Saint-Exupéry's full quote in English and the original French

For more of my opinions on and explanations of various aspects of the Chrysalis and Merriweather Park at Symphony Woods, see the Inner Arbor-related posts in the series "The Inner Arbor plan takes shape" and elsewhere on this blog. (Note that some of these posts contain outdated information relating to park features that were later dropped or revised.)

An "Inner Arbor/Inner Harbor" slide in McCall's concept plan presentation made this comparison explicit, overlaying an outline of the new downtown Columbia area on the Inner Harbor area. ↩

The phrase "beyond the berm" refers to the traditional practice of separating outdoor amphitheaters from their surroundings by a earthen embankment ("berm"). ↩

As it happens the fountain proposed in the Inner Arbor concept plan is directly south of one of the entrances proposed for the public park, which in turn is at the same location as the main park entrance and staircase in the previous plan for Symphony Woods Park. The positioning of the proposed fountain thus harks back to the north-south axial alignment characteristic of previous plans for Symphony Woods, although per the Planning Board's recommendations the Inner Arbor plan dispenses with the overly rigid pathway alignment of those plans. ↩

Frank firstname.lastname@example.com explore the vision for a new park in Symphony Woods and the strategy to implement it