Would project harm Silver Creek?
The Silver Creek water system near Picabo is the stuff of legend for anglers. Acclaimed author Ernest Hemingway made the area around what is now the Silver Creek Preserve a favorite haunt, and people from as far away as Scarsdale, N.Y., and Danville, Calif., have recently copped to their passion for the region in letters to Blaine County.
So it’s no wonder that a large-scale project proposed for the Kilpatrick Pond portion of Silver Creek has stirred up controversy. County Commissioner Larry Schoen said during a meeting last month that he believes the amount of public comment on the proposed waterway renovations was among the highest he had ever seen.
“There’s a lot of passion on this issue,” he said.
Two separate projects have been proposed, projects which Dayna Gross, Silver Creek watershed manager for The Nature Conservancy, said have been in the works for over 20 years. The Nature Conservancy manages the protected Silver Creek Preserve.
Gross said species in the system, including rainbow trout and invertebrates, rely on relatively cold water to survive. However, a dam built more than 100 years ago across the stream to provide water for irrigation is causing a temperature spike in the system, she said.
While The Nature Conservancy has a dredging plan of its own, most comment seems to center on the diversion dam and the accompanying Kilpatrick Pond, both of which are the subject of a stream alteration permit requested by the Picabo Livestock ranching operation.
The dam, built on property owned by Picabo Livestock, created the Kilpatrick Pond at the beginning of the last century and resulted in a large amount of sedimentation. The proposals from The Nature Conservancy and Nick Purdy, owner of Picabo Livestock, propose replacing the dam, dredging the pond and using the sediment to fill in areas of the pond, creating wetlands and narrowing the channel.
Charles Brockway Jr., partner in Brockway Engineering, said last month that new channels dividing what is currently Kilpatrick Pond into two “flow paths” will not be too narrow for safe and enjoyable fishing, whether from a float tube or using waders.
A report from Brockway states that the pond currently has “excessively wide, shallow conditions” that not only can harm aquatic life, but which also makes it difficult for Purdy to divert agricultural water.
Brockway’s project description, included in his application for a stream alteration permit, states that construction would begin with the insertion of a large water-filled bladder known as a coffer dam into the stream channel upstream of the pond.
The dam would divert all of the water from the pond into an enlarged irrigation ditch, and the water would be returned to the system 450 feet downstream, essentially drying out the project area and allowing for work to be completed in the pond. Brockway said this work would take place during low flows in fall and winter.
Once the coffer dam is in place, the existing 100-year-old diversion dam downstream of the pond would be replaced with a concrete dam. The new dam would allow water to flow over the top, as with the current dam, but cooler water from the bottom of the channel would be allowed to flow under the dam as well. Trout would be able to use a fish ladder to get over the dam during migration.
While the pond is dry, 15,900 cubic yards of sediment would be dredged and excavated from the bottom of the pond. Part of this sediment, roughly 4,350 cubic yards, would then be used to create wetlands in what is currently the center and southwestern areas of the pond. Sediment would be used to build banks, which would be stabilized through sod and vegetation.
The remainder of the sediment would be dispersed along the banks of the pond above the high water mark.
The Idaho Department of Fish and Game, represented by Magic Valley Region supervisor Jerome Hansen, stated in a letter dated November 2012 that if the project can be proven to lower water temperature in the area, the project would produce an “overall benefit” to cold water fish species in the system.
“The project will either benefit the cold water fish community or have a neutral impact,” Hansen wrote.
But statements approving the project from The Nature Conservancy, the U.S. Army Corps of Engineers and the Department of Environmental Quality have been dismissed by some members of the public, who wrote statements opposing the project.
Jeremy Silvis, a fishing guide for Sturtevants Mountain Outfitters, stated in a letter that he worries the narrower channels would become too crowded with people for adequate fishing, and that the channels would be too narrow for floating tubes to pass.
David Glasscock, a fishing guide with Picabo-based Idaho Angling Services, sent seven letters to the Blaine County Land Use and Building Services department opposing the project. Glasscock said he’s not convinced water temperatures impact trout populations in Kilpatrick Pond.
But other outfitters have said they disagree. Greg Loomis, another fishing guide with Sturtevants Mountain Outfitters, said Glasscock did not have reliable data to support his claims. Loomis said he’s seen insect populations and rainbow trout populations in the area decrease as a result of increasing water temperature caused by the low-flowing pond, and he’s seen fishing improve in restored areas of Silver Creek over the past few years.
Schoen said he is not sure when the next public hearing on the matter will be held, but that it would be after the Idaho Department of Water Resources provides its thoughts on the project.
“Their permits and conditions are a precursor to any decision by us, under [county] code,” he said Tuesday.
Schoen said the county is still accepting public comment on the project. An unscientific poll taken by the Idaho Mountain Express in late March showed that 71 percent of readers were opposed to the project; however, comments submitted to the county so far are 71 comments in favor, 31 opposed.