Chapter Three

Lake Washington Case Study

John T. Lehman, Professor in the Department of Ecology and Evolutionary Biology, University of Michigan 

3.4   "Seattle began discharging raw sewage into Lake Washington at the start of the twentieth century.  The large (86.5 km²) and deep basin became the repository of street and septic discharges as the city expanded eastward from Puget Sound.  In 1926, however, Seattle created a bond issue for a series of intercepting and trunk sewers to divert sewage from Lake Washington to a treatment plant on the Duwamish River that discharged directly into Puget Sound.    By 1941, the last sewer outfall into Lake Washington from Seattle had been removed.

3.5   Thereafter, water quality in the lake reflected development not of Seattle, but of its suburbs. Between 1941 and 1953, ten sewage treatment plants began operating at points around the lake, with a combined daily effluent of 80 million liters. Alternative discharge options were not as readily available to the small municipalities as they had been to Seattle. By 1953, James Ellis, a lawyer whose clients included some of the sewer districts around Lake Washington, sought diversion of sewage from Bellevue, but could not get the cooperation of neighboring districts for the necessary routing. He therefore spoke to the Seattle-King County Municipal League, proposing a system of metropolitan organization that could oversee such regional issues.

3.6   While these first steps were being discussed in the political arena, scientific investigations of Lake Washington attracted public notice with release of Technical Bulletin 18 of the Washington Pollution Control Commission, An Investigation of Pollution Effects in Lake Washington (1952-1953) (Peterson, 1955). This was the first substantial report of nutrient enrichment of the lake. It cited the work and data of Anderson (1954) and Comita (1953), who had conducted their doctoral studies under the guidance of W. T. Edmondson of the University of Washington. The Seattle Times trumpeted the report with its July 11, 1955, article, "Lake's Play Use Periled by Pollution." The Times returned to the issue a month later, when it reported the complaints of lakeshore residents and spectators at the Gold Cup yacht races (August 11, "Algae Increase Noted in Lake Washington"). Sanitation authorities doubted that the problems stemmed from the increased entry of effluent into the lake. They blamed sunshine, weather, and water conditions for the changes. It turned out, however, that the conditions of the lake that day triggered a new dimension of scientific curiosity in Edmondson's laboratory. Anderson had returned from the lake with a water sample containing an alga never encountered during his doctoral investigations of the lake: the blue-green alga (cyanobacterium) Oscillatoria rubescens."

3.7   "To Edmondson, the appearance of Oscillatoria signaled that the lake was deteriorating in classical fashion. The large, deep lakes of Western Europe, particularly Lake Zurich, had been similarly enriched with high nutrient effluents decades earlier, and water quality had declined. A series of lakes near Madison, Wisconsin, had received treated discharges from that municipality and had deteriorated. Accounts of these cases were in the scientific literature (Hasler, 1947), and Edmondson was struck by the fact that the name Oscillatoria appeared in each account in connection with the earliest stages of decline. For Lake Washington, previous data were available for comparison from 1933 (Scheffer and Robinson 1939) and from 1949-1950 (Comita and Anderson, 1959). The doctoral studies of Anderson and Comita and the earlier investigation from 1933 provided a baseline by which to judge changes (Edmondson et al, 1956). The main change in the watershed had been the increased load of nutrients from secondary-treatment waste discharge. Edmondson shared his observations in the October 13, 1955, University of Washington Daily ("Edmondson Announces Pollution May Ruin Lake"), recounting the appearance of Oscillatoria and its likely meaning. He defined his own interest as observing and analyzing the transitional nature of the lake and adding to the research done in Germany and Switzerland.

3.8   By 1956, the stage was set for developments that would bring civic leaders and scientists together. The scientists took the first step. Edmondson and two University of Washington engineering faculty members, R. O. Sylvester and R.H. Bogan, published a popular-science article in the university's journal The Trend in Engineering, "A New Critical Phase of the Lake Washington Pollution Problem" (Sylvester et al, 1956). The article told the history of sewage treatment for the area, described the problems posed by nutrient enrichment, and proposed three procedures for solution: comprehensive regional administration and planning, complete elimination of sewage discharge into Lake Washington, and research on the relationships among temperature, nutrients, and algal growth. It provided a concise layman's explanation of nutrient enrichment and its effects, including the appearance of O. rubescens, and it focused particularly on enrichment with the mineral nutrient phosphorus and the difficulty of removing it from sewage. The Seattle Times publicized the article with the headline (April 18, 1956), "Lesson of Switzerland Lakes Brought Home to Seattle Area." By October, Edmondson and a new postdoctoral associate, J. Shapiro, had received funds from the National Institutes of Health to study water chemistry and photosynthesis by algae in Lake Washington."

3.9   "In December 1956, Edmondson wrote a letter to James Ellis that marked his first involvement in the public action. James Ellis had been appointed chairman of Seattle's newly established Metropolitan Problems Advisory Committee by Mayor Gordon Clinton, and Edmondson wanted to ensure that Ellis and the committee understood that even well-treated sewage contained enough nutrients to stimulate the growth of plants in the lake. Lake Washington was already showing signs of the same series of changes toward deterioration as had been observed elsewhere.   As his initial letter had produced a cordial and positive response from Ellis, Edmondson sent him, on February 13, 1957, a nine-page summary of the effect of drainage and effluent entry into Lake Washington. The letter was phrased as a question-and-answer document and included references to theprofessional literature. Edmondson listed answers to 15 questions that he thought Ellis might be asked in connection with his work on the advisory committee—such questions as: How has Lake Washington changed? What will happen if fertilization continues? Why not poison the algae? Edmondson included a rudimentary nutrient budget for the lake constructed from available data, and he developed his case that the mass of algae present varied in strict proportion to the amounts of fertilizing nutrients added to the water. The letter included a mass of limnological cause-and-effect reasoning phrased in jargonless, objective tones. Ellis responded enthusiastically within the week, requesting copies of the letter for distribution to interested groups.

3.10   The initiative passed back to the political arena for the remainder of 1957. The immediate obstacle was the absence of provisions whereby municipalities could combine some of their government functions in comprehensive regional matters. Moreover, the notion faced opposition from some, on the grounds that it smacked of "big government."  The next step required action at the state level.

3.11   That aim was met when the Washington state legislature passed a bill permitting the establishment of a metropolitan government ("Metro") with specified functions (Ch. 217, Laws of 1957). The floor manager in the House had been Daniel J. Evans, a first-term representative, former King County engineer, and future governor. The act permitted the formation of a metropolitan government with any or all of six functions: water supply, sewage and garbage disposal, transportation, comprehensive planning, and park administration. Establishment of a Metro would require passage of a public referendum."

3.12   "The first effort to win public acceptance for spending money to clean up the lake occurred in March 1958, when a proposal to establish a Metro charged with sewage disposal, transportation, and comprehensive planning was placed on the ballot. The proposal won 54.4% of the vote, but was defeated through a complicated system of weighting votes separately in Seattle and the rest of King County. Many people outside Seattle believed that the plan was an effort to tax them for the expenses of the city. Ellis and his committee revised the scope of their plan, targeting only water pollution control and reflecting the urgency posed by the deteriorating state of Lake Washington. A revised proposal, with the single function of sewage disposal, was approved on September 9, 1958, winning 58% of the vote in Seattle and 67% in the rest of the county.

3.13   Lake Washington obviously had become a focus of regional concern among the numerous communities that populated its shores. The water and beaches served for recreation, and the lake itself was deemed of aesthetic value. A genuine sense of pride and responsibility is evident in the political arguments that surrounded the issue. Citizens were asked to undertake, at the expense of about $2 per month for each household served, a public project of sewage diversion that was at the time the most costly pollution control effort in the nation. The plan called for construction of a massive trunk sewer to divert all effluent from around the lake, to treat it, and to discharge it at great depth in Puget Sound. Tidal flushing guaranteed that objectionable quantities of nutrients would not accumulate in the estuary.

3.14   Edmondson played no part in the partisan politics, but his scientific knowledge and judgment were a deciding asset in the Metro campaign. By supplying facts and generally making himself available to answer questions from the mass media or private citizens, he provided the authority that backed the movement with facts and logic. Ellis praised Edmondson's stand years afterward for providing the facts needed to quiet the critics. When he spoke, Ellis reported, "he made us feel that the Lord God was standing right behind us on this one" (Chasan, 1971, p. 11). Privately and professionally, Edmondson reported the Lake Washington case as an experiment in lake fertilization. His scientific publications during this period traced the departure of chemical and biological conditions from the historical conditions and attempted to discern the general quantitative relationships between nutrient additions and primary productivity in lakes."

3.15   "Edmondson had been able to predict in his letter to Ellis of February 1957 a serious and rapid decline in water quality.

3.16   He wrote: "Within a few years we can expect to have serious scum and odor nuisances.  Judging by the speed with which the process has gone in other lakes, I would expect distinct trouble here within five years, although isolated occurrences might come earlier."

3.17   The important elements of his predictions that gave heart to the proponents of the diversion plan were that Edmondson thought that the lake had not yet been irreversibly damaged and that diversion would lead to a decrease in the abundance of blue-green algae. These were the plants that clouded the fertilized water, rafted to shore, and decomposed or otherwise fouled the lake. His predictions were based on fundamental principles of mass balance, stoichiometry [measuring the quantitative relationships among substances as they participate in chemical reactions], and an opinion that, to a large degree, changes in lake conditions are reversible when factors forcing the changes are reversed.

3.18  The specific basis for quantitative predictions was a conceptual and graphic model that related changes in lake properties from known initial conditions to changes in nutrients (Edmondson, 1979). The model assumed a limited return of nutrients from sediment deposits on the basis of chemical conditions in the lake and work done decades earlier in Germany and England (Mortimer, 1941, 1942; Ohle, 1934). Finally, it required knowledge of the lake's water budget, to permit calculation of a rate of dilution. From these basic facts and hypotheses, it was possible to project not only the speed of deterioration, but also the rate of recovery with different diversion schemes.

3.19 Years later, the same ideas were used by other limnologists to construct mathematical models of lake conditions in response to nutrient income and hydrology (Piontelli and Tonolli, 1964; Vollenweider, 1969, 1975, 1976); and the principles remain guiding tenets of modern lake management (Chapra and Reckhow, 1983; Reckhow, 1979). From a strictly scientific viewpoint, the exercise encouraged thought about nutrient budgets and helped to integrate studies of lakes with their watersheds. Equally important, the scientific studies helped to elaborate the quantitative links between nutrients and productivity."

3.20   "Many limnologists of the early twentieth century had been trained in the shadow of Forbes's (1925) philosophical essay "The Lake as a Microcosm" and had confined their investigations within lakeshore boundaries. Forbes himself took a much broader view of lakes and their watersheds than the title suggests, but most limnologists at the time began and ended their studies at the shoreline. Edmondson, however, had visited Wisconsin as a graduate student while C. N. Sawyer was laboring to construct the first budgets of fertilization for the lakes at Madison (Sawyer, 1947). The perspective he gained was holistic and comprehensive. The new view might better be termed "the lake in an ecosystem." Groundbreaking ceremonies for the new project were held in July 1961. Meanwhile, the lake deteriorated according to predictions. On July 3, 1962, the Seattle Post-Intelligencer reported "Lake Washington Brown— That's Algae, Not Mud and It'll Be There For the Next 10 Years." Visibility in lake water had declined from 4 m in 1950 to less than 1 m by 1962. The first diversions were slated for the next year, and, on the basis of the timetable for later diversions, Edmondson estimated that the lake would revert to its condition of 1949 by about 5 years after completion of the project. By October 5, 1963, the Post- Intelligencer had dubbed Lake Washington "Lake Stinko," with nuisance conditions at their peak just before effluent diversion.

3.21   The rest of the public record is a series of congratulatory editorials and progress reports in city and suburban newspapers. One by one, waste treatment plants around the lake had their effluent diverted. The first diversion was in 1963, and the last was in 1968. The trend of deterioration stopped in 1964; conditions that summer were no worse than in 1963. By 1965, it was apparent that water transparency, algal abundance, and phosphate concentrations were improving. On November 19, 1965, Edmondson predicted in his address to Sigma Xi, the scientific research society, that the lake would return to its pre-1950s condition within 6 years and that it would be possible to see the bottom as deep as 6 m. In the previous summer, he had made the same prediction to K. Wuhrmann, a sceptical colleague from Zurich. At meetings of the International Association for Theoretical and Applied Limnology, Wuhrmann had argued that sediment release of phosphorus would extend the recovery for decades. The scientists disagreed about one of the principal hypotheses that Edmondson had used for his quantitative predictions.

3.22   Phosphorus arrives at the sediments in the form of detrital material that decomposes more slowly than it becomes buried. Thus, the water only a few millimeters below the surface would contain great reservoirs of phosphate ions that owed their presence to the rich conditions of eutrophication. If the ions diffused through porous and unconsolidated sediment back into the water, they could renew productivity from that "internal" source."

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