title: Sons of Liberty

text: In Boston, another example of violence could be found in their treatment of local stamp distributor Andrew Oliver. They burned his effigy in the streets. When he did not resign, they escalated to burning down his office building. Even after he resigned, they almost destroyed the whole house of his close associate Lieutenant Governor Thomas Hutchinson. It is believed that the Sons of Liberty did this to excite the lower classes and get them actively involved in rebelling against the authorities. Their actions made many of the stamp distributors resign in fear.


title: Sons of Liberty

text: To celebrate the repeal of the Stamp Act in 1766, the Sons of Liberty in Dedham, Massachusetts erected the Pillar of Liberty.


title: Sons of Liberty

text: The Sons of Liberty popularized the use of tar and feathering to punish and humiliate offending government officials starting in 1767. This method was also used against British Loyalists during the American Revolution. This punishment had long been used by sailors to punish their mates.


title: Sons of Liberty

text: There was nothing "secret" about the Sons of Liberty in Boston: on August 14th 1769, they held a public rally in celebration of the 4th Anniversary of their founding. At 11 in the morning they gathered at the Liberty Tree in Boston where they gave speeches and made toasts; they then paraded to the Liberty Tree Tavern in nearby Dorchester, where they held a celebratory dinner of 300 members of the organization in a tent set up next to the tavern, where "Music played, and at proper Intervals Cannon were fired. [...] About Five o'Clock the Company left [the tavern] in a Procession that extended near a Mile and a half, and before Dark entered the City, went round the State House and retired each to his own House."


title: Sons of Liberty

text: At this time in the history of their organization they still considered themselves to be loyal subjects of the monarchy of Great Britain; when it came time at both events to give a round of toasts, the first toasts were to "The King, the Queen and the Royal Family"; only much later during the course of the Revolution did they begin to stridently oppose giving any support to the monarchy.


title: Sons of Liberty

text: The Bostonian branch of the Sons of Liberty were responsible for organizing and executing the famous Boston Tea Party of 1773 in response to the Tea Act.


title: Sons of Liberty

text: Early in the American Revolution, the former Sons of Liberty generally joined more formal groups, such as the Committee of Safety.


title: Sons of Liberty

text: "The association of the Sons of Liberty was organized in 1765, soon after the passage of the Stamp Act, and extended throughout the colonies, from Massachusetts to South Carolina. It appears that New York was the central post from which communications were dispatched, to and from the east and to the south as far as Maryland..."


title: Sons of Liberty

text: While the exact name "Sons of Liberty" may not have been taken up as their official moniker by the leaders of the New York opposition to the Stamp Act in 1765 - they were popularly known there around that time as "The Liberty Boys" - it appears that they were known to other "Sons of Liberty" organizations in other states by that name not long after that time. There is a letter written by the "Sons of Liberty" in Baltimore, Maryland, "to the Sons of Liberty in New York", dated 6 March 1766 in which the Baltimore "Sons" thanked their New York brethren for having forced Zacharias Hood, who had been appointed stamp-master for Maryland, into resigning his commission. Hood had arrived in New York on a ship from London, and as soon as his mission became known to The Liberty Boys of New York, they arranged for a meeting with him at which they reasoned with him in their own inimitable way and thus secured his "resignation."


title: Sons of Liberty

text: A list of New York members of the Sons of Liberty compiled by the Sons in Maryland, written on 1 March 1766, lists the following correspondents in the colony of New York: "New York [city] — John Lamb, Isaac Sears, William Wiley, Edward Laight, Thomas Robinson, Flores Bancker, Charles Nicoll, Joseph Allicoke, and Gershom Mott.


title: Sons of Liberty

text: John S. Hobart, Gilbert Potter, Thomas Brush, Cornelius Conklin, and Nathaniel Williams, Huntington, Long Island.


title: Sons of Liberty

text: George Townsend, Barack Sneething, Benj. Townsend, George Weeks, Michael Weeks, and Rowland Chambers, Oyster Bay, Long Island."


title: Sons of Liberty

text: In December 1773, a new group calling itself the Sons of Liberty issued and distributed a declaration in New York City called the "Association of the Sons of Liberty in New York", which formally stated that they were opposed to the Tea Act and that anyone who assisted in the execution of the act was ""an enemy to the liberties of America"" and that ""whoever shall transgress any of these resolutions, we will not deal with, or employ, or have any connection with him.""


title: Sons of Liberty

text: After the end of the American Revolutionary War, Isaac Sears, Marinus Willet, and John Lamb revived in New York City the Sons of Liberty. In March 1784, they rallied an enormous crowd that called for the expulsion of any remaining Loyalists from the state starting May 1. The Sons of Liberty were able to gain enough seats in the New York assembly elections of December 1784 to have passed a set of punitive laws against Loyalists. In violation of the Treaty of Paris (1783), they called for the confiscation of the property of Loyalists. Alexander Hamilton defended the Loyalists, citing the supremacy of the treaty.


title: Sons of Liberty

text: In 1767, the Sons of Liberty adopted a flag called the "rebellious stripes flag" with nine vertical stripes, four white and five red. A flag having 13 horizontal red and white stripes was used by Commodore Esek Hopkins (Commander-in-Chief of the Continental Navy) and by American merchant ships during the war. This flag was also associated with the Sons of Liberty. Red and white were common colors of the flags, although other color combinations were used, such as green and white or yellow and white.


title: Sons of Liberty

text: At various times, small secret organizations took the name "Sons of Liberty". They generally left very few records. Bennington, Vermont had an organization named the Sons of Liberty in the early 1800s that included local notables such as military officer Martin Scott and Hiram Harwood.


title: Sons of Liberty

text: The Improved Order of Red Men (estab. 1834) claimed to be descendants of the original Sons of Liberty, noting that the Sons participated in the Boston Tea Party dressed as their idea of "Indians".


title: Sons of Liberty

text: The name was also used during the American Civil War. The Copperhead group the Knights of the Golden Circle reorganized in 1863 as the "Order of American Knights". In 1864, it became the Order of the Sons of Liberty, with the Ohio politician Clement L. Vallandigham, most prominent of the Copperheads, as its supreme commander. In most areas only a minority of its membership was radical enough to discourage enlistments, resist the draft, and shield deserters. The group held numerous peace meetings. A few agitators, some of them encouraged by Southern money, talked of a revolt in the Old Northwest, with the goal of ending the war. Both the KGC and the Order of the Sons of Liberty came under federal prosecution in 1864 for treason, especially in Indiana.


title: Sons of Liberty

text: A radical wing of the Zionist movement launched a boycott in the U.S. against British films in 1948, in response to British policies in Palestine. It called itself the "Sons of Liberty".


title: Group (periodic table)

text: In chemistry, a group (also known as a family) is a column of elements in the periodic table of the chemical elements. There are 18 numbered groups in the periodic table; the f-block columns (between groups 2 and 3) are not numbered. The elements in a group have similar physical or chemical characteristics of the outermost electron shells of their atoms (i.e., the same core charge), because most chemical properties are dominated by the orbital location of the outermost electron.


title: Group (periodic table)

text: There are three systems of group numbering for the groups; the same number may be assigned to different groups depending on the system being used. The modern numbering system of "group 1" to "group 18" has been recommended by the International Union of Pure and Applied Chemistry (IUPAC) since about 1990. It replaces two older incompatible naming schemes, used by the Chemical Abstract Service (CAS, more popular in the US), and by IUPAC before 1990 (more popular in Europe). The system of eighteen groups is generally accepted by the chemistry community, but some dissent exists about membership of several elements. Disagreements mostly involve elements number 1 and 2 (hydrogen and helium), as well as inner transition metals.


title: Group (periodic table)

text: Groups may also be identified using their topmost element, or have a specific name. For example, group 16 is also described as the "oxygen group" and as the "chalcogens". An exception is the "iron group", which usually refers to "group 8", but in chemistry may also mean iron, cobalt, and nickel, or some other set of elements with similar chemical properties. In astrophysics and nuclear physics, it usually refers to iron, cobalt, nickel, chromium, and manganese.


title: Group (periodic table)

text: Two earlier group number systems exist: "CAS" (Chemical Abstracts Service) and "old IUPAC". Both use numerals (Arabic or Roman) and letters "A" and "B". Both systems agree on the numbers. The numbers indicate approximately the highest oxidation number of the elements in that group, and so indicate similar chemistry with other elements with the same numeral. The number proceeds in a linearly increasing fashion for the most part, once on the left of the table, and once on the right (see List of oxidation states of the elements), with some irregularities in the transition metals. However, the two systems use the letters differently. For example, potassium (K) has one valence electron. Therefore, it is located in group 1. Calcium (Ca) is in group 2, for it contains two valence electrons.


title: Group (periodic table)

text: In the old IUPAC system the letters A and B were designated to the left (A) and right (B) part of the table, while in the CAS system the letters A and B are designated to main group elements (A) and transition elements (B). The old IUPAC system was frequently used in Europe, while the CAS is most common in America. The new IUPAC scheme was developed to replace both systems as they confusingly used the same names to mean different things. The new system simply numbers the groups increasingly from left to right on the standard periodic table. The IUPAC proposal was first circulated in 1985 for public comments, and was later included as part of the 1990 edition of the "Nomenclature of Inorganic Chemistry".


title: Berghof (residence)

text: The Berghof was Adolf Hitler's vacation home in the Obersalzberg of the Bavarian Alps near Berchtesgaden, Bavaria, Germany. Other than the "Wolfsschanze" ("Wolf's Lair"), his headquarters in East Prussia for the invasion of the Soviet Union, he spent more time here than anywhere else during his time as the "Führer" of Nazi Germany. It was also one of the most widely known of his headquarters, which were located throughout Europe.


title: Berghof (residence)

text: The Berghof was rebuilt and renamed in 1935 and was Hitler's vacation residence for ten years. It was damaged by British bombs in late April 1945, and again in early May by retreating SS troops, and it was looted after Allied troops reached the area. The Bavarian government demolished the burned shell in 1952.


title: Berghof (residence)

text: The Berghof began as a much smaller chalet called "Haus Wachenfeld", a holiday home built in 1916 (or 1917) by "Kommerzienrat" Otto Winter, a businessman from Buxtehude. It was located near the "Platterhof", the former "Pension Moritz" where Hitler had stayed in 1922–23. By 1926, the family running the pension had left, and Hitler did not like the new owner. He moved first to the "Marineheim" and then to a hotel in Berchtesgaden, the "Deutsches Haus", where he dictated the second volume of "Mein Kampf" in the summer of 1926. Hitler met his girlfriend at that time, Maria Reiter, who worked in a shop on the ground floor of the hotel, during another visit in autumn 1926. In 1928, Winter's widow rented "Haus Wachenfeld" to Hitler, and his half-sister Angela came to live there as housekeeper, although she left soon after her daughter Geli's 1931 death in Hitler's Munich apartment.


title: Berghof (residence)

text: By 1933, Hitler had purchased "Haus Wachenfeld" with funds he received from the sale of his political manifesto "Mein Kampf". The small chalet-style building was refurbished and much expanded by architect during 1935–36 under the supervision of Martin Bormann, when it was renamed "The Berghof" (English: "Mountain Court").


title: Berghof (residence)

text: A large terrace was built and featured big, colourful, resort-style canvas umbrellas. The entrance hall "was filled with a curious display of cactus plants in majolica pots." A dining room was panelled with very costly cembra pine. Hitler's large study had a telephone switchboard room. The library contained books "on history, painting, architecture and music." A great hall was furnished with expensive Teutonic furniture, a large globe, and an expansive red marble fireplace mantel. Behind one wall was a projection booth for evening screenings of films (often, Hollywood productions, including Mickey Mouse).


title: Berghof (residence)

text: A sprawling picture window could be lowered into the wall to give a sweeping, open-air view of the snow-capped mountains in Hitler's native Austria. The house was maintained much like a small resort hotel by several housekeepers, gardeners, cooks, and other domestic workers. "This place is mine," Hitler was quoted as saying to a writer for "Homes & Gardens" magazine in 1938. "I built it with money that I earned."


title: Berghof (residence)

text: The British "Homes & Gardens" magazine described Hitler as "his own decorator, designer, and furnisher, as well as architect", and the chalet as "bright and airy" with "a light jade-green colour scheme"; caged Harz Roller canaries were kept in most of the rooms, which were furnished with antiques, mostly German furniture from the 18th century. Old engravings hung in the guest bedrooms, along with some of Hitler's small watercolour sketches. His personal valet Heinz Linge stated that Hitler and his longtime companion Eva Braun had two bedrooms and two bathrooms with interconnecting doors, and Hitler would end most evenings alone with her in his study drinking tea.


title: Berghof (residence)

text: Though Hitler did not smoke, smoking was allowed on the terrace. His vegetarian diet was supplied by nearby kitchen gardens and, later, a greenhouse. A large complex of mountain homes for the Nazi leadership, with a landing strip and many buildings for their security and support staff, were constructed nearby. To acquire the land for these projects, many neighbours were compelled to sell their properties and leave. A mountaintop structure, the "Kehlsteinhaus", nicknamed "Eagle's Nest" by André François-Poncet, a French diplomat, was built in 1937–38 above the Berghof, but Hitler rarely went there.


title: Berghof (residence)

text: The area became a German tourist attraction during the mid-1930s, after Hitler came to power as dictator. Visitors gathered at the end of the driveway or on nearby public paths in the hope of catching a glimpse of Hitler. This led to the introduction of severe restrictions on access to the area and other security measures. A large contingent of the "Leibstandarte SS Adolf Hitler" was housed in barracks adjacent to the Berghof. Under the command of "Obersturmbannführer" Bernhard Frank, they patrolled an extensive cordoned security zone that encompassed the nearby homes of the other Nazi leaders. With the outbreak of war extensive anti-aircraft defences were also installed, including smoke-generating machines to conceal the Berghof complex from hostile aircraft.


title: Berghof (residence)

text: The nearby former hotel "Türken" was turned into quarters to house the "Reichssicherheitsdienst" (Reich Security Service; RSD) SS security men who patrolled the grounds of the Berghof. It was later occupied by the "Generalmajor" of the Police. (The hotel was rebuilt in 1950 and reopened as a hotel before Christmas, the Hotel zum Türken. Visitors can still explore the historic underground hallways and tunnels that had been used by the Nazis.)


title: Berghof (residence)

text: Whenever Hitler was in residence, members of the RSD and "Führerbegleitkommando" (Führer Escort Command; FBK) were present. While the RSD men patrolled the grounds, the FBK men provided close security protection for Hitler. Several Wehrmacht mountain troop units were also housed nearby. Hence, the British never planned a direct attack on the compound.


title: Berghof (residence)

text: Guests at the Berghof included political figures, monarchs, heads of state, and diplomats along with painters, singers, and musicians. The important visitors personally greeted on the steps of the Berghof by Hitler included David Lloyd George (3 March 1936), the Aga Khan (20 October 1937), Duke and Duchess of Windsor (22 October 1937), Kurt von Schuschnigg (12 February 1938), Neville Chamberlain (15 September 1938), and Benito Mussolini (19 January 1941). At the end of July 1940, Hitler summoned his military chiefs from OKW and OKH to the Berghof for the 'Berghof Conference' at which the 'Russian problem' was studied. On 11 May 1941, Karlheinz Pintsch visited the Berghof to deliver a letter from Rudolf Hess informing Hitler of his illegal flight to Scotland.


title: Berghof (residence)

text: Hitler's social circle at his Berghof retreat – which his intimates referred to as "on the "Berg"" – included Eva Braun and her sister Gretl, Herta Schneider and her children, Eva's friend Marion Schönmann, Heinrich Hoffmann, and the wives and children of other Nazi leaders and Hitler's staff who would all pose for an annual group photograph on the occasion of Hitler's birthday. The social scene at the Berghof ended on 14 July 1944, when Hitler left for his military headquarters in East Prussia, never to return.


title: Berghof (residence)

text: Silent colour films shot by Eva Braun survived the war and showed Hitler and his guests relaxing at the Berghof. In 2006, computer lip-reading software identified several parts of their conversations. Among those identified in the films were Joseph Goebbels, Reinhard Heydrich, Heinrich Himmler, Joachim von Ribbentrop, Albert Speer, and Karl Wolff.


title: Berghof (residence)

text: Two guests planned to use a visit to the Berghof as an opportunity to assassinate Hitler. On 11 March 1944, Captain Eberhard von Breitenbuch arrived with a concealed pistol with the intention of shooting Hitler in the head, but guards would not allow him into the same room. On 7 June 1944, Colonel Claus Schenk Graf von Stauffenberg planned to detonate a bomb at a meeting there, but his fellow conspirators would not give him approval to do so because Himmler and Hermann Göring were also not present.


title: Berghof (residence)

text: The Allies rejected suggestions about derailing Hitler's train to Obersalzberg and using poison in the train's drinking water, but the British developed a plan named Operation Foxley in 1944. This called for a sniper to kill Hitler on his daily 15–20 minute walk from the Berghof residence to the "Teehaus" on the Mooslahnerkopf Hill, which had been revealed by a prisoner of war. The operation would be undertaken by a German-speaking Pole and a British sniper wearing German uniforms after being parachuted into Austria. They would be housed and led to the area by an anti-Nazi, identified as "Heidentaler" who lived nearby in Salzburg. The Foxley plan did not proceed, due to a dispute as to whether killing Hitler was a prudent idea and the lack of intelligence about his exact daily routine. By the time that the plan might have proceeded, Hitler had stopped visiting his mountain retreat; he never returned to the compound after 14 July 1944.


title: Berghof (residence)

text: The Obersalzberg was bombed by hundreds of British RAF Lancaster heavy bombers, including aircraft from No. 617 Squadron RAF (the "Dambusters"), which attacked Obersalzberg on 25 April 1945. At least two bombs struck the Berghof and did considerable damage to the building. Retreating SS troops set fire to the villa on 4 May, four days after Hitler's suicide in Berlin. Only hours later, the U.S. 3rd Infantry Division arrived at Berchtesgaden along with the French 2nd Armored Division. Herman Louis Finnell of the 3rd Division stated that he and Private Fungerburg were the first to enter Berghof and the secret passages below the structure. Finnell stated that the hallway below the structure had rooms on either side filled with destroyed paintings and evening gowns, as well as destroyed medical equipment and a wine cellar. A French tank crew soon joined them, and Allied soldiers thoroughly looted and stripped the house over the next few days. The American 1st Battalion of the 506th Infantry Regiment arrived on 8 May. The 3rd Battalion of the 506th came into Berchtesgaden by a different route and sustained casualties in a skirmish with the crews of two German 88mm anti-aircraft/anti-tank guns. One of the most notable artifacts taken by American soldiers was the Columbus Globe for State and Industry Leaders, known more commonly as "Hitler's Globe".


title: Berghof (residence)

text: The teahouse on Mooslahnerkopf hill was unscathed in the April 1945 bombing raid, but the Bavarian government knocked it down by 1951 because of its link with Hitler. For 55 years, the ruins lay in the woods by the 13th hole of the Gutshof golf course, but these were taken away altogether during the summer of 2006. The Berghof's shell survived until 1952, when the Bavarian government demolished it with explosives on 30 April. The Berghof, the houses of Göring and Bormann, the SS barracks, the Kampfhäusl, and the teahouse were all destroyed. This had been part of an agreement under which the Americans handed the area back to the Bavarian authorities. There was fear that the ruins would become a neo-Nazi shrine and tourist attraction.


title: Berghof (residence)

text: More than 50 Obersalzberg Nazi buildings were destroyed. The Platterhof had been a nearby hostel for visitors to the area, and it was turned into the General Walker Hotel for American troops after the war. It was demolished in 2001.


title: Berghof (residence)

text: The Berghof was one of the headquarters used by Hitler during the war. There were about 14 known completed "Führer" Headquarters.


title: Caitlin McHugh

text: Born in Santa Monica, California to Leilani (née Empeno) and Timothy McHugh, she attended Flintridge Sacred Heart Academy in La Cañada Flintridge, California, graduating in 2004. She is of Irish and Filipino ancestry.


title: Caitlin McHugh

text: She first began to find bit parts in film and television in 2007 with a minor role in "I Am Legend", and earned nine more credits over the next six years. In 2014, she portrayed Sloan in the fifth season of the TV series "The Vampire Diaries". In 2017, she co-wrote the romantic comedy short film "Ingenue-ish" with fellow actor John Stamos, who also co-starred with her.


title: Caitlin McHugh

text: McHugh is signed with Wilhelmina Models. In 2016, she appeared in television commercials for Colgate toothpaste and the following year, for the Buick Encore.


title: Caitlin McHugh

text: McHugh married restaurateur Massimo Lusardi on June 3, 2011. They separated a few months later and divorced in 2014.


title: Caitlin McHugh

text: In 2011, McHugh met actor John Stamos when they both guest-starred on an episode of "". They began dating in 2016 and became engaged in October 2017. They married in February 2018, and their son was born in April 2018.


title: Waterfall model

text: The waterfall model is a breakdown of project activities into linear sequential phases, meaning they are passed down onto each other, where each phase depends on the deliverables of the previous one and corresponds to a specialization of tasks. The approach is typical for certain areas of engineering design. In software development, it tends to be among the less iterative and flexible approaches, as progress flows in largely one direction ("downwards" like a waterfall) through the phases of conception, initiation, analysis, design, construction, testing, deployment and maintenance.


title: Waterfall model

text: The waterfall development model originated in the manufacturing and construction industries, where the highly structured physical environments meant that design changes became prohibitively expensive much sooner in the development process. When first adopted for software development, there were no recognised alternatives for knowledge-based creative work.


title: Waterfall model

text: The first known presentation describing use of such phases in software engineering was held by Felix Torres and Herbert D. Benington at the Symposium on Advanced Programming Methods for Digital Computers on 29 June 1956. This presentation was about the development of software for SAGE. In 1983 the paper was republished with a foreword by Benington explaining that the phases were on purpose organised according to the specialisation of tasks, and pointing out that the process was not in fact performed in a strict top-down fashion, but depended on a prototype.


title: Waterfall model

text: Although the term "waterfall" is not used in the paper, the first formal detailed diagram of the process later known as the "waterfall model" is often cited as a 1970 article by Winston W. Royce. However he also felt it had major flaws stemming from the fact that testing only happened at the end of the process, which he described as being "risky and invites failure". The rest of his paper introduced five steps which he felt were necessary to "eliminate most of the development risks" associated with the unaltered waterfall approach.


title: Waterfall model

text: Royce's five additional steps (which included writing complete documentation at various stages of development) never took mainstream hold, but his diagram of what he considered a flawed process became the starting point when describing a "waterfall" approach.


title: Waterfall model

text: In 1985, the United States Department of Defense captured this approach in DOD-STD-2167A, their standards for working with software development contractors, which stated that "the contractor shall implement a software development cycle that includes the following six phases: Software Requirement Analysis, Preliminary Design, Detailed Design, Coding and Unit Testing, Integration, and Testing".


title: Waterfall model

text: Thus the waterfall model maintains that one should move to a phase only when its preceding phase is reviewed and verified.


title: Waterfall model

text: Various modified waterfall models (including Royce's final model), however, can include slight or major variations on this process. These variations included returning to the previous cycle after flaws were found downstream, or returning all the way to the design phase if downstream phases deemed insufficient.


title: Waterfall model

text: Time spent early in the software production cycle can reduce costs at later stages. For example, a problem found in the early stages (such as requirements specification) is cheaper to fix than the same bug found later on in the process (by a factor of 50 to 200).


title: Waterfall model

text: In common practice, waterfall methodologies result in a project schedule with 20–40% of the time invested for the first two phases, 30–40% of the time to coding, and the rest dedicated to testing and implementation. The actual project organisation needs to be highly structured. Most medium and large projects will include a detailed set of procedures and controls, which regulate every process on the project.


title: Waterfall model

text: A further argument for the waterfall model is that it places emphasis on documentation (such as requirements documents and design documents) as well as source code. In less thoroughly designed and documented methodologies, knowledge is lost if team members leave before the project is completed, and it may be difficult for a project to recover from the loss. If a fully working design document is present (as is the intent of Big Design Up Front and the waterfall model), new team members or even entirely new teams should be able to familiarise themselves by reading the documents.


title: Waterfall model

text: The waterfall model provides a structured approach; the model itself progresses linearly through discrete, easily understandable and explainable phases and thus is easy to understand; it also provides easily identifiable milestones in the development process. It is perhaps for this reason that the waterfall model is used as a beginning example of a development model in many software engineering texts and courses.


title: Waterfall model

text: Clients may not know exactly what their requirements are before they see working software and so change their requirements, leading to redesign, redevelopment, and retesting, and increased costs.


title: Waterfall model

text: Designers may not be aware of future difficulties when designing a new software product or feature, in which case it is better to revise the design than persist in a design that does not account for any newly discovered constraints, requirements, or problems.


title: Waterfall model

text: Organisations may attempt to deal with a lack of concrete requirements from clients by employing systems analysts to examine existing manual systems and analyse what they do and how they might be replaced. However, in practice, it is difficult to sustain a strict separation between systems analysis and programming. This is because implementing any non-trivial system will almost inevitably expose issues and edge cases that the systems analyst did not consider.


title: Waterfall model

text: In response to the perceived problems with the "pure" waterfall model, modified waterfall models were introduced, such as "Sashimi (Waterfall with Overlapping Phases), Waterfall with Subprojects, and Waterfall with Risk Reduction".


title: Waterfall model

text: Some organisations, such as the United States Department of Defense, now have a stated preference against waterfall-type methodologies, starting with MIL-STD-498 released in 1994, which encourages "evolutionary acquisition" and "Iterative and Incremental Development".


title: Waterfall model

text: While advocates of agile software development argue the waterfall model is an ineffective process for developing software, some sceptics suggest that the waterfall model is a false argument used purely to market "alternative" development methodologies.


title: Waterfall model

text: Rational Unified Process (RUP) phases acknowledge the programmatic need for milestones, for keeping a project on track, but encourage iterations (especially within Disciplines) within the Phases. RUP Phases are often referred to as "waterfall-like".


title: Waterfall model

text: In response to the perceived problems with the "pure" waterfall model, many modified waterfall models have been introduced. These models may address some or all of the criticisms of the "pure" waterfall model.


title: Waterfall model

text: These include the Rapid Development models that Steve McConnell calls "modified waterfalls": Peter DeGrace's "sashimi model" (waterfall with overlapping phases), waterfall with subprojects, and waterfall with risk reduction. Other software development model combinations such as "incremental waterfall model" also exist.


title: Waterfall model

text: Winston W. Royce's final model, his intended improvement upon his initial "waterfall model", illustrated that feedback could (should, and often would) lead from code testing to design (as testing of code uncovered flaws in the design) and from design back to requirements specification (as design problems may necessitate the removal of conflicting or otherwise unsatisfiable / undesignable requirements). In the same paper Royce also advocated large quantities of documentation, doing the job "twice if possible" (a sentiment similar to that of Fred Brooks, famous for writing the Mythical Man Month, an influential book in software project management, who advocated planning to "throw one away"), and involving the customer as much as possible (a sentiment similar to that of extreme programming).


title: John Spencer (actor)

text: John Spencer (born John Speshock Jr.; December 20, 1946 – December 16, 2005) was an American actor. He was best known for his role as Leo McGarry on the NBC political drama series "The West Wing" and for his role as attorney Tommy Mullaney in L.A. Law. His performance on "The West Wing" earned him a Primetime Emmy Award in 2002.


title: John Spencer (actor)

text: John Spencer was born John Speshock Jr., on December 20, 1946, in New York City, and was raised in Totowa, New Jersey. He was the son of blue-collar parents Mildred (née Benzeroski), a waitress, and John Speshock Sr., a truck driver. Spencer's father was of Irish and Czech descent, while his mother was of Ukrainian and Rusyn ancestry. Spencers parents were disappointed when he chose to become an actor. With his enrollment at the Professional Children's School in Manhattan in 1963, Spencer found himself sharing classes with such fellow students as Liza Minnelli and violinist Pinchas Zukerman. He attended Fairleigh Dickinson University, but did not complete a degree. Spencer often referred to himself as a "dyed-in-the-wool liberal" and described Franklin Delano Roosevelt as one of his heroes.


title: John Spencer (actor)

text: Spencer began his television career on "The Patty Duke Show", and eventually began appearing in supporting roles in feature films commencing with 1983's "WarGames". He won an Obie Award for the 1981 off Broadway production of "Still Life", about a Vietnam War veteran, and received a Drama Desk nomination for "The Day Room". In 1986 he appeared on Broadway as Dan White, the killer of Harvey Milk, in "Execution of Justice", alongside Stanley Tucci and Wesley Snipes. Spencer became a full-fledged supporting actor with the hit 1990 courtroom thriller "Presumed Innocent", portraying a tough veteran homicide detective, starring opposite Harrison Ford. Spencer's work also extended to video games, portraying the role of Captain Hugh Paulsen in the 1995 video game "". Spencer's subsequent film and television work primarily consisted of supporting roles such as a colleague and friend to Billy Crystal's basketball ref in "Forget Paris" and a prickly FBI official in Michael Bay's film "The Rock".


title: John Spencer (actor)

text: In 1990 Spencer joined the cast of the television series "L.A. Law", playing street wise attorney Tommy Mullaney from 1990-1994. Spencer originally wasn't going to take the role but after reading 5 pages of the script he was convinced and said "it was one of the best scripts I’d read". Spencer said his character’s disheveled wardrobe was based on his own. Spencer said he and co star Cecil Hoffman spent time in New York City to prepare for the role.


title: John Spencer (actor)

text: In 1999, Spencer was cast as Leo McGarry on the NBC political drama series "The West Wing". Spencer's character was White House Chief of Staff to fictional U.S. President Josiah Bartlet. Like Spencer, McGarry was a recovering alcoholic and compulsive worker. McGarry's character was also a former US Air force pilot who served in the Vietnam War.


title: John Spencer (actor)

text: Spencer's character would later be chosen as Jimmy Smits' character's running mate. Spencer's role on the show earned him the Primetime Emmy Award for Outstanding Supporting Actor in a Drama Series in 2002, for the show's third season episodes "Bartlet for America" and "We Killed Yamamoto."


title: John Spencer (actor)

text: Spencer died of a heart attack in a Los Angeles hospital on December 16, 2005, four days before his 59th birthday. At his private funeral, his "West Wing" castmate, Kristin Chenoweth, sang the musical number "For Good" from the Broadway musical "Wicked". Spencer's remains were interred at Laurel Grove Memorial Park in his hometown of Totowa, New Jersey.


title: John Spencer (actor)

text: Several paid tribute to him, including Martin Sheen, Dulé Hill, Joshua Malina, Janel Moloney, Richard Schiff, Alan Alda, Jimmy Smits, Aaron Sorkin, Allison Janney, James Mangold, David E. Kelley, Bradley Whitford.


title: John Spencer (actor)

text: At the time of his death, Spencer had filmed two "West Wing" episodes that were in post-production – "Running Mates" and "The Cold" – in which he and Jimmy Smits played candidates for vice president and president, respectively.


title: Columbia River

text: The Columbia River (Upper Chinook: ' or '; Sahaptin: "Nch’i-Wàna" or "Nchi wana"; Sinixt dialect" ") is the largest river in the Pacific Northwest region of North America. The river rises in the Rocky Mountains of British Columbia, Canada. It flows northwest and then south into the U.S. state of Washington, then turns west to form most of the border between Washington and the state of Oregon before emptying into the Pacific Ocean. The river is long, and its largest tributary is the Snake River. Its drainage basin is roughly the size of France and extends into seven US states and a Canadian province. The fourth-largest river in the United States by volume, the Columbia has the greatest flow of any North American river entering the Pacific. The Columbia has the 36th greatest discharge of any river in the world.


title: Columbia River

text: The Columbia and its tributaries have been central to the region's culture and economy for thousands of years. They have been used for transportation since ancient times, linking the region's many cultural groups. The river system hosts many species of anadromous fish, which migrate between freshwater habitats and the saline waters of the Pacific Ocean. These fish—especially the salmon species—provided the core subsistence for native peoples.


title: Columbia River

text: The first documented European discovery of the Columbia River occurred when Bruno de Heceta sighted the river's mouth in 1775. On May 11, 1792, a private American ship, Columbia Rediviva, under Captain Robert Gray from Boston became the first non-indigenous vessel to enter the river. Later in 1792, William Robert Broughton of the British Royal Navy commanding the HMS "Chatham" as part of the Vancouver Expedition, navigated past the Oregon Coast Range and 100 miles upriver [Voyages of the Columbia on the Northwest Coast. Frederic W. Howay]to what is now Vancouver, Washington. In the following decades, fur-trading companies used the Columbia as a key transportation route. Overland explorers entered the Willamette Valley through the scenic, but treacherous Columbia River Gorge, and pioneers began to settle the valley in increasing numbers. Steamships along the river linked communities and facilitated trade; the arrival of railroads in the late 19th century, many running along the river, supplemented these links.


title: Columbia River

text: Since the late 19th century, public and private sectors have extensively developed the river. To aid ship and barge navigation, locks have been built along the lower Columbia and its tributaries, and dredging has opened, maintained, and enlarged shipping channels. Since the early 20th century, dams have been built across the river for power generation, navigation, irrigation, and flood control. The 14 hydroelectric dams on the Columbia's main stem and many more on its tributaries produce more than 44 percent of total U.S. hydroelectric generation. Production of nuclear power has taken place at two sites along the river. Plutonium for nuclear weapons was produced for decades at the Hanford Site, which is now the most contaminated nuclear site in the United States. These developments have greatly altered river environments in the watershed, mainly through industrial pollution and barriers to fish migration.


title: Columbia River

text: The Columbia begins its journey in the southern Rocky Mountain Trench in British Columbia (BC). Columbia Lake – above sea level – and the adjoining Columbia Wetlands form the river's headwaters. The trench is a broad, deep, and long glacial valley between the Canadian Rockies and the Columbia Mountains in BC. For its first , the Columbia flows northwest along the trench through Windermere Lake and the town of Invermere, a region known in British Columbia as the Columbia Valley, then northwest to Golden and into Kinbasket Lake. Rounding the northern end of the Selkirk Mountains, the river turns sharply south through a region known as the Big Bend Country, passing through Revelstoke Lake and the Arrow Lakes. Revelstoke, the Big Bend, and the Columbia Valley combined are referred to in BC parlance as the Columbia Country. Below the Arrow Lakes, the Columbia passes the cities of Castlegar, located at the Columbia's confluence with the Kootenay River, and Trail, two major population centers of the West Kootenay region. The Pend Oreille River joins the Columbia about north of the U.S.–Canada border.


title: Columbia River

text: The Columbia enters eastern Washington flowing south and turning to the west at the Spokane River confluence. It marks the southern and eastern borders of the Colville Indian Reservation and the western border of the Spokane Indian Reservation. The river turns south after the Okanogan River confluence, then southeasterly near the confluence with the Wenatchee River in central Washington. This C‑shaped segment of the river is also known as the "Big Bend". During the Missoula Floods 10,000 to 15,000 years ago, much of the floodwater took a more direct route south, forming the ancient river bed known as the Grand Coulee. After the floods, the river found its present course, and the Grand Coulee was left dry. The construction of the Grand Coulee Dam in the mid-20th century impounded the river, forming Lake Roosevelt, from which water was pumped into the dry coulee, forming the reservoir of Banks Lake.


title: Columbia River

text: The river flows past The Gorge Amphitheatre, a prominent concert venue in the Northwest, then through Priest Rapids Dam, and then through the Hanford Nuclear Reservation. Entirely within the reservation is Hanford Reach, the only US stretch of the river that is completely free-flowing, unimpeded by dams, and not a tidal estuary. The Snake River and Yakima River join the Columbia in the Tri-Cities population center. The Columbia makes a sharp bend to the west at the Washington–Oregon border. The river defines that border for the final of its journey.


title: Columbia River

text: The Deschutes River joins the Columbia near The Dalles. Between The Dalles and Portland, the river cuts through the Cascade Range, forming the dramatic Columbia River Gorge. No other rivers except for the Klamath and Pit River completely breach the Cascades—the other rivers that flow through the range also originate in or very near the mountains. The headwaters and upper course of the Pit River are on the Modoc Plateau; downstream, the Pit cuts a canyon through the southern reaches of the Cascades. In contrast, the Columbia cuts through the range nearly a thousand miles from its source in the Rocky Mountains. The gorge is known for its strong and steady winds, scenic beauty, and its role as an important transportation link. The river continues west, bending sharply to the north-northwest near Portland and Vancouver, Washington, at the Willamette River confluence. Here the river slows considerably, dropping sediment that might otherwise form a river delta. Near Longview, Washington and the Cowlitz River confluence, the river turns west again. The Columbia empties into the Pacific Ocean just west of Astoria, Oregon, over the Columbia Bar, a shifting sandbar that makes the river's mouth one of the most hazardous stretches of water to navigate in the world. Because of the danger and the many shipwrecks near the mouth, it acquired a reputation as the "Graveyard of Ships".


title: Columbia River

text: The Columbia drains an area of about . Its drainage basin covers nearly all of Idaho, large portions of British Columbia, Oregon, and Washington, ultimately all of Montana west of the Continental Divide, and small portions of Wyoming, Utah, and Nevada; the total area is similar to the size of France. Roughly of the river's length and 85 percent of its drainage basin are in the US. The Columbia is the twelfth-longest river and has the sixth-largest drainage basin in the United States. In Canada, where the Columbia flows for and drains , the river ranks 23rd in length, and the Canadian part of its basin ranks 13th in size among Canadian basins.


title: Columbia River

text: The Columbia shares its name with nearby places, such as British Columbia, as well as with landforms and bodies of water.


title: Columbia River

text: With an average flow at the mouth of about , the Columbia is the largest river by discharge flowing into the Pacific from the Americas and is the fourth-largest by volume in the US. The average flow where the river crosses the international border between Canada and the United States is from a drainage basin of . This amounts to about 15 percent of the entire Columbia watershed. The Columbia's highest recorded flow, measured at The Dalles, was in June 1894, before the river was dammed. The lowest flow recorded at The Dalles was on April 16, 1968, and was caused by the initial closure of the John Day Dam, upstream. The Dalles is about from the mouth; the river at this point drains about or about 91 percent of the total watershed. Flow rates on the Columbia are affected by many large upstream reservoirs, many diversions for irrigation, and, on the lower stretches, reverse flow from the tides of the Pacific Ocean. The National Ocean Service observes water levels at six tide gauges and issues tide forecasts for twenty-two additional locations along the river between the entrance at the North Jetty and the base of Bonneville Dam, the head of tide.


title: Columbia River

text: When the rifting of Pangaea, due to the process of plate tectonics, pushed North America away from Europe and Africa and into the Panthalassic Ocean (ancestor to the modern Pacific Ocean), the Pacific Northwest was not part of the continent. As the North American continent moved westward, the Farallon Plate subducted under its western margin. As the plate subducted, it carried along island arcs which were accreted to the North American continent, resulting in the creation of the Pacific Northwest between 150 and 90 million years ago. The general outline of the Columbia Basin was not complete until between 60 and 40 million years ago, but it lay under a large inland sea later subject to uplift. Between 50 and 20 million years ago, from the Eocene through the Miocene eras, tremendous volcanic eruptions frequently modified much of the landscape traversed by the Columbia. The lower reaches of the ancestral river passed through a valley near where Mount Hood later arose. Carrying sediments from erosion and erupting volcanoes, it built a thick delta that underlies the foothills on the east side of the Coast Range near Vernonia in northwestern Oregon. Between 17 million and 6 million years ago, huge outpourings of flood basalt lava covered the Columbia River Plateau and forced the lower Columbia into its present course. The modern Cascade Range began to uplift 5 to 4 million years ago. Cutting through the uplifting mountains, the Columbia River significantly deepened the Columbia River Gorge.


title: Columbia River

text: The river and its drainage basin experienced some of the world's greatest known catastrophic floods toward the end of the last ice age. The periodic rupturing of ice dams at Glacial Lake Missoula resulted in the Missoula Floods, with discharges exceeding the combined flow of all the other rivers in the world, dozens of times over thousands of years. The exact number of floods is unknown, but geologists have documented at least 40; evidence suggests that they occurred between about 19,000 and 13,000 years ago.


title: Columbia River

text: The floodwaters rushed across eastern Washington, creating the channeled scablands, which are a complex network of dry canyon-like channels, or coulees that are often braided and sharply gouged into the basalt rock underlying the region's deep topsoil. Numerous flat-topped buttes with rich soil stand high above the chaotic scablands. Constrictions at several places caused the floodwaters to pool into large temporary lakes, such as Lake Lewis, in which sediments were deposited. Water depths have been estimated at at Wallula Gap and over modern Portland, Oregon. Sediments were also deposited when the floodwaters slowed in the broad flats of the Quincy, Othello, and Pasco Basins. The floods' periodic inundation of the lower Columbia River Plateau deposited rich sediments; 21st-century farmers in the Willamette Valley "plow fields of fertile Montana soil and clays from Washington's Palouse".


title: Columbia River

text: Over the last several thousand years a series of large landslides have occurred on the north side of the Columbia River Gorge, sending massive amounts of debris south from Table Mountain and Greenleaf Peak into the gorge near the present site of Bonneville Dam. The most recent and significant is known as the Bonneville Slide, which formed a massive earthen dam, filling of the river's length. Various studies have placed the date of the Bonneville Slide anywhere between 1060 and 1760 AD; the idea that the landslide debris present today was formed by more than one slide is relatively recent and may explain the large range of estimates. It has been suggested that if the later dates are accurate there may be a link with the 1700 Cascadia earthquake. The pile of debris resulting from the Bonneville Slide blocked the river until rising water finally washed away the sediment. It is not known how long it took the river to break through the barrier; estimates range from several months to several years. Much of the landslide's debris remained, forcing the river about south of its previous channel and forming the Cascade Rapids. In 1938, the construction of Bonneville Dam inundated the rapids as well as the remaining trees that could be used to refine the estimated date of the landslide.


title: Columbia River

text: In 1980, the eruption of Mount St. Helens deposited large amounts of sediment in the lower Columbia, temporarily reducing the depth of the shipping channel by .


title: Columbia River

text: Humans have inhabited the Columbia's watershed for more than 15,000 years, with a transition to a sedentary lifestyle based mainly on salmon starting about 3,500 years ago. In 1962, archaeologists found evidence of human activity dating back 11,230 years at the Marmes Rockshelter, near the confluence of the Palouse and Snake rivers in eastern Washington. In 1996 the skeletal remains of a 9,000-year-old prehistoric man (dubbed Kennewick Man) were found near Kennewick, Washington. The discovery rekindled debate in the scientific community over the origins of human habitation in North America and sparked a protracted controversy over whether the scientific or Native American community was entitled to possess and/or study the remains.


title: Columbia River

text: Many different Native Americans and First Nations peoples have a historical and continuing presence on the Columbia. South of the Canada–US border, the Colville, Spokane, Coeur d'Alene, Yakama, Nez Perce, Cayuse, Palus, Umatilla, Cowlitz, and the Confederated Tribes of Warm Springs live along the US stretch. Along the upper Snake River and Salmon River, the Shoshone Bannock tribes are present. The Sinixt or Lakes people lived on the lower stretch of the Canadian portion, while above that the Shuswap people (Secwepemc in their own language) reckon the whole of the upper Columbia east to the Rockies as part of their territory. The Canadian portion of the Columbia Basin outlines the traditional homelands of the Canadian Kootenay–Ktunaxa.


title: Columbia River

text: The Chinook tribe, which is not federally recognized, who live near the lower Columbia River, call it ' or ' in the Upper Chinook (Kiksht) language, and it is "Nch’i-Wàna" or "Nchi wana" to the Sahaptin (Ichishkíin Sɨ́nwit)-speaking peoples of its middle course in present-day Washington. The river is known as "" by the Sinixt people, who live in the area of the Arrow Lakes in the river's upper reaches in Canada. All three terms essentially mean "the big river".


title: Columbia River

text: Oral histories describe the formation and destruction of the Bridge of the Gods, a land bridge that connected the Oregon and Washington sides of the river in the Columbia River Gorge. The bridge, which aligns with geological records of the Bonneville Slide, was described in some stories as the result of a battle between gods, represented by Mount Adams and Mount Hood, in their competition for the affection of a goddess, represented by Mount St. Helens. Native American stories about the bridge differ in their details but agree in general that the bridge permitted increased interaction between tribes on the north and south sides of the river.


title: Columbia River

text: Horses, originally acquired from Spanish New Mexico, spread widely via native trade networks, reaching the Shoshone of the Snake River Plain by 1700. The Nez Perce, Cayuse, and Flathead people acquired their first horses around 1730. Along with horses came aspects of the emerging plains culture, such as equestrian and horse training skills, greatly increased mobility, hunting efficiency, trade over long distances, intensified warfare, the linking of wealth and prestige to horses and war, and the rise of large and powerful tribal confederacies. The Nez Perce and Cayuse kept large herds and made annual long-distance trips to the Great Plains for bison hunting, adopted the plains culture to a significant degree, and became the main conduit through which horses and the plains culture diffused into the Columbia River region. Other peoples acquired horses and aspects of the plains culture unevenly. The Yakama, Umatilla, Palus, Spokane, and Coeur d'Alene maintained sizable herds of horses and adopted some of the plains cultural characteristics, but fishing and fish-related economies remained important. Less affected groups included the Molala, Klickitat, Wenatchi, Okanagan, and Sinkiuse-Columbia peoples, who owned small numbers of horses and adopted few plains culture features. Some groups remained essentially unaffected, such as the Sanpoil and Nespelem people, whose culture remained centered on fishing.


title: Columbia River

text: Natives of the region encountered foreigners at several times and places during the 18th and 19th centuries. European and American vessels explored the coastal area around the mouth of the river in the late 18th century, trading with local natives. The contact would prove devastating to the Indian tribes; a large portion of their population was wiped out by a smallpox epidemic. Canadian explorer Alexander Mackenzie crossed what is now interior British Columbia in 1793. From 1805 to 1807, the Lewis and Clark Expedition entered the Oregon Country along the Clearwater and Snake rivers, and encountered numerous small settlements of natives. Their records recount tales of hospitable traders who were not above stealing small items from the visitors. They also noted brass teakettles, a British musket, and other artifacts that had been obtained in trade with coastal tribes. From the earliest contact with westerners, the natives of the mid- and lower Columbia were not tribal, but instead congregated in social units no larger than a village, and more often at a family level; these units would shift with the season as people moved about, following the salmon catch up and down the river's tributaries.


title: Columbia River

text: Sparked by the 1847 Whitman Massacre, a number of violent battles were fought between American settlers and the region's natives. The subsequent Indian Wars, especially the Yakima War, decimated the native population and removed much land from native control. As years progressed, the right of natives to fish along the Columbia became the central issue of contention with the states, commercial fishers, and private property owners. The US Supreme Court upheld fishing rights in landmark cases in 1905 and 1918, as well as the 1974 case "United States v. Washington", commonly called the Boldt Decision.


title: Columbia River

text: Fish were central to the culture of the region's natives, both as sustenance and as part of their religious beliefs. Natives drew fish from the Columbia at several major sites, which also served as trading posts. Celilo Falls, located east of the modern city of The Dalles, was a vital hub for trade and the interaction of different cultural groups, being used for fishing and trading for 11,000 years. Prior to contact with westerners, villages along this stretch may have at times had a population as great as 10,000. The site drew traders from as far away as the Great Plains.


title: Columbia River

text: The Cascades Rapids of the Columbia River Gorge, and Kettle Falls and Priest Rapids in eastern Washington, were also major fishing and trading sites.


title: Columbia River

text: In prehistoric times the Columbia's salmon and steelhead runs numbered an estimated annual average of 10 to 16 million fish. In comparison, the largest run since 1938 was in 1986, with 3.2 million fish entering the Columbia. The annual catch by natives has been estimated at . The most important and productive native fishing site was located at Celilo Falls, which was perhaps the most productive inland fishing site in North America. The falls were located at the border between Chinookan- and Sahaptian-speaking peoples and served as the center of an extensive trading network across the Pacific Plateau. Celilo was the oldest continuously inhabited community on the North American continent.


title: Columbia River

text: Salmon canneries established by white settlers beginning in 1866 had a strong negative impact on the salmon population, and in 1908 US President Theodore Roosevelt observed that the salmon runs were but a fraction of what they had been 25 years prior.


title: Columbia River

text: As river development continued in the 20th century, each of these major fishing sites was flooded by a dam, beginning with Cascades Rapids in 1938. The development was accompanied by extensive negotiations between natives and US government agencies. The Confederated Tribes of Warm Springs, a coalition of various tribes, adopted a constitution and incorporated after the 1938 completion of the Bonneville Dam flooded Cascades Rapids; Still, in the 1930s, there were natives who lived along the river and fished year round, moving along with the fish's migration patterns throughout the seasons. The Yakama were slower to do so, organizing a formal government in 1944. In the 21st century, the Yakama, Nez Perce, Umatilla, and Warm Springs tribes all have treaty fishing rights along the Columbia and its tributaries.


title: Columbia River

text: In 1957 Celilo Falls was submerged by the construction of The Dalles Dam, and the native fishing community was displaced. The affected tribes received a $26.8 million settlement for the loss of Celilo and other fishing sites submerged by The Dalles Dam. The Confederated Tribes of Warm Springs used part of its $4 million settlement to establish the Kah-Nee-Ta resort south of Mount Hood.


title: Columbia River

text: Some historians believe that Japanese or Chinese vessels blown off course reached the Northwest Coast long before Europeans—possibly as early as 219 BCE. Historian Derek Hayes claims that "It is a near certainty that Japanese or Chinese people arrived on the northwest coast long before any European." It is unknown whether they landed near the Columbia. Evidence exists that Spanish castaways reached the shore in 1679 and traded with the Clatsop; if these were the first Europeans to see the Columbia, they failed to send word home to Spain.


title: Columbia River

text: In the 18th century, there was strong interest in discovering a Northwest Passage that would permit navigation between the Atlantic (or inland North America) and the Pacific Ocean. Many ships in the area, especially those under Spanish and British command, searched the northwest coast for a large river that might connect to Hudson Bay or the Missouri River. The first documented European discovery of the Columbia River was that of Bruno de Heceta, who in 1775 sighted the river's mouth. On the advice of his officers, he did not explore it, as he was short-staffed and the current was strong. He considered it a bay, and called it "Ensenada de Asunción" ("Assumption Cove"). Later Spanish maps, based on his sighting, showed a river, labeled "Río de San Roque" ("The Saint Roch River"), or an entrance, called "Entrada de Hezeta", named for Bruno de Hezeta, who sailed the region. Following Hezeta's reports, British maritime fur trader Captain John Meares searched for the river in 1788 but concluded that it did not exist. He named Cape Disappointment for the non-existent river, not realizing the cape marks the northern edge of the river's mouth.


title: Columbia River

text: What happened next would form the basis for decades of both cooperation and dispute between British and American exploration of, and ownership claim to, the region. Royal Navy commander George Vancouver sailed past the mouth in April 1792 and observed a change in the water's color, but he accepted Meares' report and continued on his journey northward. Later that month, Vancouver encountered the American captain Robert Gray at the Strait of Juan de Fuca. Gray reported that he had seen the entrance to the Columbia and had spent nine days trying but failing to enter.


title: Columbia River

text: On May 12, 1792, Gray returned south and crossed the Columbia Bar, becoming the first known explorer of European descent to enter the river. Gray's fur trading mission had been financed by Boston merchants, who outfitted him with a private vessel named "Columbia Rediviva"; he named the river after the ship on May 18. Gray spent nine days trading near the mouth of the Columbia, then left without having gone beyond upstream. The farthest point reached was Grays Bay at the mouth of Grays River. Gray's discovery of the Columbia River was later used by the United States to support its claim to the Oregon Country, which was also claimed by Russia, Great Britain, Spain and other nations.


title: Columbia River

text: In October 1792, Vancouver sent Lieutenant William Robert Broughton, his second-in-command, up the river. Broughton got as far as the Sandy River at the western end of the Columbia River Gorge, about upstream, sighting and naming Mount Hood. Broughton formally claimed the river, its drainage basin, and the nearby coast for Britain. In contrast, Gray had not made any formal claims on behalf of the United States.


title: Columbia River

text: Because the Columbia was at the same latitude as the headwaters of the Missouri River, there was some speculation that Gray and Vancouver had discovered the long-sought Northwest Passage. A 1798 British map showed a dotted line connecting the Columbia with the Missouri. When the American explorers Meriwether Lewis and William Clark charted the vast, unmapped lands of the American West in their overland expedition (1803–1805), they found no passage between the rivers. After crossing the Rocky Mountains, Lewis and Clark built dugout canoes and paddled down the Snake River, reaching the Columbia near the present-day Tri-Cities, Washington. They explored a few miles upriver, as far as Bateman Island, before heading down the Columbia, concluding their journey at the river's mouth and establishing Fort Clatsop, a short-lived establishment that was occupied for less than three months.


title: Columbia River

text: Canadian explorer David Thompson, of the North West Company, spent the winter of 1807–08 at Kootanae House near the source of the Columbia at present-day Invermere, British Columbia. Over the next few years he explored much of the river and its northern tributaries. In 1811 he traveled down the Columbia to the Pacific Ocean, arriving at the mouth just after John Jacob Astor's Pacific Fur Company had founded Astoria. On his return to the north, Thompson explored the one remaining part of the river he had not yet seen, becoming the first Euro-descended person to travel the entire length of the river.


title: Columbia River

text: In 1825, the Hudson's Bay Company (HBC) established Fort Vancouver on the bank of the Columbia, in what is now Vancouver, Washington, as the headquarters of the company's Columbia District, which encompassed everything west of the Rocky Mountains, north of California, and south of Russian-claimed Alaska. Chief Factor John McLoughlin, a physician who had been in the fur trade since 1804, was appointed superintendent of the Columbia District. The HBC reoriented its Columbia District operations toward the Pacific Ocean via the Columbia, which became the region's main trunk route. In the early 1840s Americans began to colonize the Oregon country in large numbers via the Oregon Trail, despite the HBC's efforts to discourage American settlement in the region. For many the final leg of the journey involved travel down the lower Columbia River to Fort Vancouver. This part of the Oregon Trail, the treacherous stretch from The Dalles to below the Cascades, could not be traversed by horses or wagons (only watercraft, at great risk). This prompted the 1846 construction of the Barlow Road.


title: Columbia River

text: In the Treaty of 1818 the United States and Britain agreed that both nations were to enjoy equal rights in Oregon Country for 10 years. By 1828, when the so-called "joint occupation" was renewed for an indefinite period, it seemed probable that the lower Columbia River would in time become the border between the two nations. For years the Hudson's Bay Company successfully maintained control of the Columbia River and American attempts to gain a foothold were fended off. In the 1830s, American religious missions were established at several locations in the lower Columbia River region. In the 1840s a mass migration of American settlers undermined British control. The Hudson's Bay Company tried to maintain dominance by shifting from the fur trade, which was in decline, to exporting other goods such as salmon and lumber. Colonization schemes were attempted, but failed to match the scale of American settlement. Americans generally settled south of the Columbia, mainly in the Willamette Valley. The Hudson's Bay Company tried to establish settlements north of the river, but nearly all the British colonists moved south to the Willamette Valley. The hope that the British colonists might dilute the American presence in the valley failed in the face of the overwhelming number of American settlers. These developments rekindled the issue of "joint occupation" and the boundary dispute. While some British interests, especially the Hudson's Bay Company, fought for a boundary along the Columbia River, the Oregon Treaty of 1846 set the boundary at the 49th parallel. As part of the treaty, the British retained all areas north of the line while the U.S. acquired the south. The Columbia River became much of the border between the U.S. territories of Oregon and Washington. Oregon became a U.S. state in 1859, while Washington later entered into the Union in 1889.


title: Columbia River

text: By the turn of the 20th century, the difficulty of navigating the Columbia was seen as an impediment to the economic development of the Inland Empire region east of the Cascades. The dredging and dam building that followed would permanently alter the river, disrupting its natural flow but also providing electricity, irrigation, navigability and other benefits to the region.


title: Columbia River

text: American captain Robert Gray and British captain George Vancouver, who explored the river in 1792, proved that it was possible to cross the Columbia Bar. Many of the challenges associated with that feat remain today; even with modern engineering alterations to the mouth of the river, the strong currents and shifting sandbar make it dangerous to pass between the river and the Pacific Ocean.


title: Columbia River

text: The use of steamboats along the river, beginning with the British "Beaver" in 1836 and followed by American vessels in 1850, contributed to the rapid settlement and economic development of the region. Steamboats operated in several distinct stretches of the river: on its lower reaches, from the Pacific Ocean to Cascades Rapids; from the Cascades to the Dalles-Celilo Falls; from Celilo to Priests Rapids; on the Wenatchee Reach of eastern Washington; on British Columbia's Arrow Lakes; and on tributaries like the Willamette, the Snake and Kootenay Lake. The boats, initially powered by burning wood, carried passengers and freight throughout the region for many years. Early railroads served to connect steamboat lines interrupted by waterfalls on the river's lower reaches. In the 1880s, railroads maintained by companies such as the Oregon Railroad and Navigation Company began to supplement steamboat operations as the major transportation links along the river.


title: Columbia River

text: As early as 1881, industrialists proposed altering the natural channel of the Columbia to improve navigation. Changes to the river over the years have included the construction of jetties at the river's mouth, dredging, and the construction of canals and navigation locks. Today, ocean freighters can travel upriver as far as Portland and Vancouver, and barges can reach as far inland as Lewiston, Idaho.


title: Columbia River

text: The shifting Columbia Bar makes passage between the river and the Pacific Ocean difficult and dangerous, and numerous rapids along the river hinder navigation. "Pacific Graveyard," a 1964 book by James A. Gibbs, describes the many shipwrecks near the mouth of the Columbia. Jetties, first constructed in 1886, extend the river's channel into the ocean. Strong currents and the shifting sandbar remain a threat to ships entering the river and necessitate continuous maintenance of the jetties.


title: Columbia River

text: In 1891, the Columbia was dredged to enhance shipping. The channel between the ocean and Portland and Vancouver was deepened from to . "The Columbian" called for the channel to be deepened to as early as 1905, but that depth was not attained until 1976.


title: Columbia River

text: Cascade Locks and Canal were first constructed in 1896 around the Cascades Rapids, enabling boats to travel safely through the Columbia River Gorge. The Celilo Canal, bypassing Celilo Falls, opened to river traffic in 1915. In the mid-20th century, the construction of dams along the length of the river submerged the rapids beneath a series of reservoirs. An extensive system of locks allowed ships and barges to pass easily from one reservoir to the next. A navigation channel reaching to Lewiston, Idaho, along the Columbia and Snake rivers, was completed in 1975. Among the main commodities are wheat and other grains, mainly for export. As of 2016, the Columbia ranked third, behind the Mississippi and Paraná rivers, among the world's largest export corridors for grain.


title: Columbia River

text: The 1980 eruption of Mount St. Helens caused mudslides in the area, which reduced the Columbia's depth by for a stretch, disrupting Portland's economy.


title: Columbia River

text: Efforts to maintain and improve the navigation channel have continued to the present day. In 1990 a new round of studies examined the possibility of further dredging on the lower Columbia. The plans were controversial from the start because of economic and environmental concerns.


title: Columbia River

text: In 1999, Congress authorized deepening the channel between Portland and Astoria from , which will make it possible for large container and grain ships to reach Portland and Vancouver. The project has met opposition because of concerns about stirring up toxic sediment on the riverbed. Portland-based Northwest Environmental Advocates brought a lawsuit against the Army Corps of Engineers, but it was rejected by the Ninth U.S. Circuit Court of Appeals in August 2006. The project includes measures to mitigate environmental damage; for instance, the US Army Corps of Engineers must restore 12 times the area of wetland damaged by the project. In early 2006, the Corps spilled of hydraulic oil into the Columbia, drawing further criticism from environmental organizations.


title: Columbia River

text: Work on the project began in 2005 and concluded in 2010. The project's cost is estimated at $150 million. The federal government is paying 65 percent, Oregon and Washington are paying $27 million each, and six local ports are also contributing to the cost.


title: Columbia River

text: In 1902, the United States Bureau of Reclamation was established to aid in the economic development of arid western states. One of its major undertakings was building Grand Coulee Dam to provide irrigation for the of the Columbia Basin Project in central Washington. With the onset of World War II, the focus of dam construction shifted to production of hydroelectricity. Irrigation efforts resumed after the war.


title: Columbia River

text: River development occurred within the structure of the 1909 International Boundary Waters Treaty between the US and Canada. The United States Congress passed the Rivers and Harbors Act of 1925, which directed the Army Corps of Engineers and the Federal Power Commission to explore the development of the nation's rivers. This prompted agencies to conduct the first formal financial analysis of hydroelectric development; the reports produced by various agencies were presented in House Document 308. Those reports, and subsequent related reports, are referred to as 308 Reports.


title: Columbia River

text: In the late 1920s, political forces in the Northwestern United States generally favored private development of hydroelectric dams along the Columbia. But the overwhelming victories of gubernatorial candidate George W. Joseph in the 1930 Republican primary, and later his law partner Julius Meier, were understood to demonstrate strong public support for public ownership of dams. In 1933, President Franklin D. Roosevelt signed a bill that enabled the construction of the Bonneville and Grand Coulee dams as public works projects. The legislation was attributed to the efforts of Oregon Senator Charles McNary, Washington Senator Clarence Dill, and Oregon Congressman Charles Martin, among others.


title: Columbia River

text: In 1948, floods swept through the Columbia watershed, destroying Vanport, then the second largest city in Oregon, and impacting cities as far north as Trail, British Columbia. The flooding prompted the United States Congress to pass the Flood Control Act of 1950, authorizing the federal development of additional dams and other flood control mechanisms. By that time local communities had become wary of federal hydroelectric projects, and sought local control of new developments; a public utility district in Grant County, Washington, ultimately began construction of the dam at Priest Rapids.


title: Columbia River

text: In the 1960s, the United States and Canada signed the Columbia River Treaty, which focused on flood control and the maximization of downstream power generation. Canada agreed to build dams and provide reservoir storage, and the United States agreed to deliver to Canada one-half of the increase in US downstream power benefits as estimated five years in advance. Canada's obligation was met by building three dams (two on the Columbia, and one on the Duncan River), the last of which was completed in 1973.


title: Columbia River

text: Today the main stem of the Columbia River has 14 dams, of which three are in Canada and 11 in the US. Four mainstem dams and four lower Snake River dams contain navigation locks to allow ship and barge passage from the ocean as far as Lewiston, Idaho. The river system as a whole has more than 400 dams for hydroelectricity and irrigation. The dams address a variety of demands, including flood control, navigation, stream flow regulation, storage and delivery of stored waters, reclamation of public lands and Indian reservations, and the generation of hydroelectric power.


title: Columbia River

text: The larger U.S. dams are owned and operated by the federal government (some by the Army Corps of Engineers and some by the Bureau of Reclamation), while the smaller dams are operated by public utility districts, and private power companies. The federally operated system is known as the Federal Columbia River Power System, which includes 31 dams on the Columbia and its tributaries. The system has altered the seasonal flow of the river in order to meet higher electricity demands during the winter. At the beginning of the 20th century, roughly 75 percent of the Columbia's flow occurred in the summer, between April and September. By 1980, the summer proportion had been lowered to about 50 percent, essentially eliminating the seasonal pattern.


title: Columbia River

text: The installation of dams dramatically altered the landscape and ecosystem of the river. At one time, the Columbia was one of the top salmon-producing river systems in the world. Previously active fishing sites, such as Celilo Falls in the eastern Columbia River Gorge, have exhibited a sharp decline in fishing along the Columbia in the last century, and salmon populations have been dramatically reduced. Fish ladders have been installed at some dam sites to help the fish journey to spawning waters. Chief Joseph Dam has no fish ladders and completely blocks fish migration to the upper half of the Columbia River system.


title: Columbia River

text: The Bureau of Reclamation's Columbia Basin Project focused on the generally dry region of central Washington known as the Columbia Basin, which features rich loess soil. Several groups developed competing proposals, and in 1933, President Franklin D. Roosevelt authorized the Columbia Basin Project. The Grand Coulee Dam was the project's central component; upon completion, it pumped water up from the Columbia to fill the formerly dry Grand Coulee, forming Banks Lake. By 1935, the intended height of the dam was increased from a range between to , a height that would extend the lake impounded by the dam all the way to the Canada–US border; the project had grown from a local New Deal relief measure to a major national project.


title: Columbia River

text: The project's initial purpose was irrigation, but the onset of World War II created a high demand for electricity, mainly for aluminum production and for the development of nuclear weapons at the Hanford Site. Irrigation began in 1951. The project provides water to more than of fertile but arid land in central Washington, transforming the region into a major agricultural center. Important crops include orchard fruit, potatoes, alfalfa, mint, beans, beets, and wine grapes.


title: Columbia River

text: Since 1750, the Columbia has experienced six multi-year droughts. The longest, lasting 12 years in the mid‑19th century, reduced the river's flow to 20 percent below average. Scientists have expressed concern that a similar drought would have grave consequences in a region so dependent on the Columbia. In 1992–1993, a lesser drought affected farmers, hydroelectric power producers, shippers, and wildlife managers.


title: Columbia River

text: Many farmers in central Washington build dams on their property for irrigation and to control frost on their crops. The Washington Department of Ecology, using new techniques involving aerial photographs, estimated there may be as many as a hundred such dams in the area, most of which are illegal. Six such dams have failed in recent years, causing hundreds of thousands of dollars of damage to crops and public roads. Fourteen farms in the area have gone through the permitting process to build such dams legally.


title: Columbia River

text: The Columbia's heavy flow and large elevation drop over a short distance, , give it tremendous capacity for hydroelectricity generation. In comparison, the Mississippi drops less than . The Columbia alone possesses one-third of the United States's hydroelectric potential. In 2012, the river and its tributaries accounted for 29 GW of hydroelectric generating capacity, contributing 44 percent of the total hydroelectric generation in the nation.


title: Columbia River

text: The largest of the 150 hydroelectric projects, the Grand Coulee Dam and the Chief Joseph Dam, are also the largest in the United States. As of 2017, Grand Coulee is the fifth largest hydroelectric plant in the world.


title: Columbia River

text: Inexpensive hydropower supported the location of a large aluminum industry in the region, because its reduction from bauxite requires large amounts of electricity. Until 2000, the Northwestern United States produced up to 17 percent of the world's aluminum and 40 percent of the aluminum produced in the United States. The commoditization of power in the early 21st century, coupled with drought that reduced the generation capacity of the river, damaged the industry and by 2001, Columbia River aluminum producers had idled 80 percent of its production capacity. By 2003, the entire United States produced only 15 percent of the world's aluminum, and many smelters along the Columbia had gone dormant or out of business.


title: Columbia River

text: Power remains relatively inexpensive along the Columbia, and since the mid-2000 several global enterprises have moved server farm operations into the area to avail themselves of cheap power. Downriver of Grand Coulee, each dam's reservoir is closely regulated by the Bonneville Power Administration (BPA), the U.S. Army Corps of Engineers, and various Washington public utility districts to ensure flow, flood control, and power generation objectives are met. Increasingly, hydro-power operations are required to meet standards under the US Endangered Species Act and other agreements to manage operations to minimize impacts on salmon and other fish, and some conservation and fishing groups support removing four dams on the lower Snake River, the largest tributary of the Columbia.


title: Columbia River

text: In 1941, the BPA hired Oklahoma folksinger Woody Guthrie to write songs for a documentary film promoting the benefits of hydropower. In the month he spent traveling the region Guthrie wrote 26 songs, which have become an important part of the cultural history of the region.


title: Columbia River

text: The Columbia supports several species of anadromous fish that migrate between the Pacific Ocean and fresh water tributaries of the river. Sockeye salmon, Coho and Chinook (also known as "king") salmon, and steelhead, all of the genus "Oncorhynchus", are ocean fish that migrate up the rivers at the end of their life cycles to spawn. White sturgeon, which take 15 to 25 years to mature, typically migrate between the ocean and the upstream habitat several times during their lives.


title: Columbia River

text: Salmon populations declined dramatically after the establishment of canneries in 1867. In 1879 it was reported that 545,450 salmon, with an average weight of were caught (in a recent season) and mainly canned for export to England. A can weighing could be sold for 8d or 9d. By 1908, there was widespread concern about the decline of salmon and sturgeon. In that year, the people of Oregon passed two laws under their newly instituted program of citizens' initiatives limiting fishing on the Columbia and other rivers. Then in 1948, another initiative banned the use of seine nets (devices already used by Native Americans, and refined by later settlers) altogether.


title: Columbia River

text: Dams interrupt the migration of anadromous fish. Salmon and steelhead return to the streams in which they were born to spawn; where dams prevent their return, entire populations of salmon die. Some of the Columbia and Snake River dams employ fish ladders, which are effective to varying degrees at allowing these fish to travel upstream. Another problem exists for the juvenile salmon headed downstream to the ocean. Previously, this journey would have taken two to three weeks. With river currents slowed by the dams, and the Columbia converted from wild river to a series of slackwater pools, the journey can take several months, which increases the mortality rate. In some cases, the Army Corps of Engineers transports juvenile fish downstream by truck or river barge. The Chief Joseph Dam and several dams on the Columbia's tributaries entirely block migration, and there are no migrating fish on the river above these dams. Sturgeon have different migration habits and can survive without ever visiting the ocean. In many upstream areas cut off from the ocean by dams, sturgeon simply live upstream of the dam.


title: Columbia River

text: Not all fish have suffered from the modifications to the river; the northern pikeminnow (formerly known as the "squawfish") thrives in the warmer, slower water created by the dams. Research in the mid-1980s found that juvenile salmon were suffering substantially from the predatory pikeminnow, and in 1990, in the interest of protecting salmon, a "bounty" program was established to reward anglers for catching pikeminnow.


title: Columbia River

text: In 1994, the salmon catch was smaller than usual in the rivers of Oregon, Washington, and British Columbia, causing concern among commercial fishermen, government agencies, and tribal leaders. US government intervention, to which the states of Alaska, Idaho, and Oregon objected, included an 11-day closure of an Alaska fishery. In April 1994 the Pacific Fisheries Management Council unanimously approved the strictest regulations in 18 years, banning all commercial salmon fishing for that year from Cape Falcon north to the Canada–US border. In the winter of 1994, the return of coho salmon far exceeded expectations, which was attributed in part to the fishing ban.


title: Columbia River

text: Also in 1994, United States Secretary of the Interior Bruce Babbitt first proposed the removal of several Pacific Northwest dams because of their impact on salmon spawning. The Northwest Power Planning Council approved a plan that provided more water for fish and less for electricity, irrigation, and transportation. Environmental advocates have called for the removal of certain dams in the Columbia system in the years since. Of the 227 major dams in the Columbia River drainage basin, the four Washington dams on the lower Snake River are often identified for removal, for example in an ongoing lawsuit concerning a Bush administration plan for salmon recovery. These dams and reservoirs limit the recovery of upriver salmon runs to Idaho's Salmon and Clearwater rivers. Historically, the Snake produced over 1.5 million spring and summer Chinook salmon, a number that has dwindled to several thousand in recent years. Idaho Power Company's Hells Canyon dams have no fish ladders (and do not pass juvenile salmon downstream), and thus allow no steelhead or salmon to migrate above Hells Canyon. In 2007, the destruction of the Marmot Dam on the Sandy River was the first dam removal in the system. Other Columbia Basin dams that have been removed include Condit Dam on Washington's White Salmon River, and the Milltown Dam on the Clark Fork in Montana.


title: Columbia River

text: In southeastern Washington, a stretch of the river passes through the Hanford Site, established in 1943 as part of the Manhattan Project. The site served as a plutonium production complex, with nine nuclear reactors and related facilities along the banks of the river. From 1944 to 1971, pump systems drew cooling water from the river and, after treating this water for use by the reactors, returned it to the river. Before being released back into the river, the used water was held in large tanks known as retention basins for up to six hours. Longer-lived isotopes were not affected by this retention, and several terabecquerels entered the river every day. By 1957, the eight plutonium production reactors at Hanford dumped a daily average of 50,000 curies of radioactive material into the Columbia. These releases were kept secret by the federal government until the release of declassified documents in the late 1980s. Radiation was measured downstream as far west as the Washington and Oregon coasts.


title: Columbia River

text: The nuclear reactors were decommissioned at the end of the Cold War, and the Hanford site is the focus of one of the world's largest environmental cleanup, managed by the Department of Energy under the oversight of the Washington Department of Ecology and the Environmental Protection Agency. Nearby aquifers contain an estimated 270 billion US gallons (1 billion m) of groundwater contaminated by high-level nuclear waste that has leaked out of Hanford's underground storage tanks. , 1 million US gallons (3,785 m) of highly radioactive waste is traveling through groundwater toward the Columbia River. This waste is expected to reach the river in 12 to 50 years if cleanup does not proceed on schedule.


title: Columbia River

text: In addition to concerns about nuclear waste, numerous other pollutants are found in the river. These include chemical pesticides, bacteria, arsenic, dioxins, and polychlorinated biphenyls (PCB).


title: Columbia River

text: Studies have also found significant levels of toxins in fish and the waters they inhabit within the basin. Accumulation of toxins in fish threatens the survival of fish species, and human consumption of these fish can lead to health problems. Water quality is also an important factor in the survival of other wildlife and plants that grow in the Columbia River drainage basin. The states, Indian tribes, and federal government are all engaged in efforts to restore and improve the water, land, and air quality of the Columbia River drainage basin and have committed to work together to enhance and accomplish critical ecosystem restoration efforts. A number of cleanup efforts are currently underway, including Superfund projects at Portland Harbor, Hanford, and Lake Roosevelt.


title: Columbia River

text: Timber industry activity further contaminates river water, for example in the increased sediment runoff that results from clearcuts. The Northwest Forest Plan, a piece of federal legislation from 1994, mandated that timber companies consider the environmental impacts of their practices on rivers like the Columbia.


title: Columbia River

text: On July 1, 2003, Christopher Swain of Portland, Oregon, became the first person to swim the Columbia River's entire length, in an effort to raise public awareness about the river's environmental health.


title: Columbia River

text: Both natural and anthropogenic processes are involved in the cycling of nutrients in the Columbia River basin. Natural processes in the system include estuarine mixing of fresh and ocean waters, and climate variability patterns such as the Pacific Decadal Oscillation and the El Nino Southern Oscillation (both climatic cycles that affect the amount of regional snowpack and river discharge). Natural sources of nutrients in the Columbia River include weathering, leaf litter, salmon carcasses, runoff from its tributaries, and ocean estuary exchange. Major anthropogenic impacts to nutrients in the basin are due to fertilizers from agriculture, sewage systems, logging, and the construction of dams.


title: Columbia River

text: Nutrients dynamics vary in the river basin from the headwaters to the main river and dams, to finally reaching the Columbia River estuary and ocean. Upstream in the headwaters, salmon runs are the main source of nutrients. Dams along the river impact nutrient cycling by increasing residence time of nutrients, and reducing the transport of silicate to the estuary, which directly impacts diatoms, a type of phytoplankton. The dams are also a barrier to salmon migration, and can increase the amount of methane locally produced. The Columbia River estuary exports high rates of nutrients into the Pacific Ocean; with the exception of nitrogen, which is delivered into the estuary by ocean upwelling sources.


title: Columbia River

text: Most of the Columbia's drainage basin (which, at , is about the size of France) lies roughly between the Rocky Mountains on the east and the Cascade Mountains on the west. In the United States and Canada the term watershed is often used to mean drainage basin. The term "Columbia Basin" is used to refer not only to the entire drainage basin but also to subsets of the river's full watershed, such as the relatively flat and unforested area in eastern Washington bounded by the Cascades, the Rocky Mountains, and the Blue Mountains. Within the watershed are diverse landforms including mountains, arid plateaus, river valleys, rolling uplands, and deep gorges. Grand Teton National Park lies in the watershed, as well as parts of Yellowstone National Park, Glacier National Park, Mount Rainier National Park, and North Cascades National Park. Canadian National Parks in the watershed include Kootenay National Park, Yoho National Park, Glacier National Park, and Mount Revelstoke National Park. Hells Canyon, the deepest gorge in North America, and the Columbia Gorge are in the watershed. Vegetation varies widely, ranging from western hemlock and western redcedar in the moist regions to sagebrush in the arid regions. The watershed provides habitat for 609 known fish and wildlife species, including the bull trout, bald eagle, gray wolf, grizzly bear, and Canada lynx.


title: Columbia River

text: The World Wide Fund for Nature (WWF) divides the waters of the Columbia and its tributaries into three freshwater ecoregions, naming them Columbia Glaciated, Columbia Unglaciated, and Upper Snake. The Columbia Glaciated ecoregion, making up about a third of the total watershed, lies in the north and was covered with ice sheets during the Pleistocene. The ecoregion includes the mainstem Columbia north of the Snake River and tributaries such as the Yakima, Okanagan, Pend Oreille, Clark Fork, and Kootenay rivers. The effects of glaciation include a number of large lakes and a relatively low diversity of freshwater fish. The Upper Snake ecoregion is defined as the Snake River watershed above Shoshone Falls, which totally blocks fish migration. This region has 14 species of fish, many of which are endemic. The Columbia Unglaciated ecoregion makes up the rest of the watershed. It includes the mainstem Columbia below the Snake River and tributaries such as the Salmon, John Day, Deschutes, and lower Snake Rivers. Of the three ecoregions it is the richest in terms of freshwater species diversity. There are 35 species of fish, of which four are endemic. There are also high levels of mollusk endemism.


title: Columbia River

text: In 2016, over eight million people lived within the Columbia's drainage basin. Of this total about 3.5 million people lived in Oregon, 2.1 million in Washington, 1.7 million in Idaho, half a million in British Columbia, and 0.4 million in Montana. Population in the watershed has been rising for many decades and is projected to rise to about 10 million by 2030. The highest population densities are found west of the Cascade Mountains along the I-5 corridor, especially in the Portland-Vancouver urban area. High densities are also found around Spokane, Washington, and Boise, Idaho. Although much of the watershed is rural and sparsely populated, areas with recreational and scenic values are growing rapidly. The central Oregon county of Deschutes is the fastest-growing in the state. Populations have also been growing just east of the Cascades in central Washington around the city of Yakima and the Tri-Cities area. Projections for the coming decades assume growth throughout the watershed, including the interior. The Canadian part of the Okanagan subbasin is also growing rapidly.


title: Columbia River

text: Climate varies greatly from place to place within the watershed. Elevation ranges from sea level at the river mouth to more than in the mountains, and temperatures vary with elevation. The highest peak is Mount Rainier, at . High elevations have cold winters and short cool summers; interior regions are subject to great temperature variability and severe droughts. Over some of the watershed, especially west of the Cascade Mountains, precipitation maximums occur in winter, when Pacific storms come ashore. Atmospheric conditions block the flow of moisture in summer, which is generally dry except for occasional thunderstorms in the interior. In some of the eastern parts of the watershed, especially shrub-steppe regions with Continental climate patterns, precipitation maximums occur in early summer. Annual precipitation varies from more than a year in the Cascades to less than in the interior. Much of the watershed gets less than a year.


title: Columbia River

text: Several major North American drainage basins and many minor ones share a common border with the Columbia River's drainage basin. To the east, in northern Wyoming and Montana, the Continental Divide separates the Columbia watershed from the Mississippi-Missouri watershed, which empties into the Gulf of Mexico. To the northeast, mostly along the southern border between British Columbia and Alberta, the Continental Divide separates the Columbia watershed from the Nelson-Lake Winnipeg-Saskatchewan watershed, which empties into Hudson Bay. The Mississippi and Nelson watersheds are separated by the Laurentian Divide, which meets the Continental Divide at Triple Divide Peak near the headwaters of the Columbia's Flathead River tributary. This point marks the meeting of three of North America's main drainage patterns, to the Pacific Ocean, to Hudson Bay, and to the Atlantic Ocean via the Gulf of Mexico.