That its water quality today is as good or better than at any other time in its history is due to a unique blend of scientific judgment and public action.
--John T. Lehman,
Division of Biological Sciences,
University of Michigan, Ann Arbor
In 1955, a postdoctoral researcher working with UW zoology professor W.Thomas Edmondson went sailing on Lake Washington and noticed a funny color. The lake water appeared cloudier than George Anderson had remembered from the days when he was a graduate student studying the lake.
Scientific investigation of Lake Washington had been attracting public attention in those days, especially with the release in 1955 of a Washington Pollution Control Commission bulletin, the first substantial report of the buildup of pollutants in the lake. The report cited the work of Anderson in 1954 and of Comita, 1953, both of whom had conducted graduate research at the UW with Edmondson. When the bulletin was released, the Seattle Times picked it up, with the July 11, 1955 headline "Lake's Play Use Periled by Pollution." Residents around the lake and spectators at the Gold Cup yacht races in August of that year noticed changes in the water quality, and again the Times took note with its August 11 article, "Algae Increase Noted in Lake Washington."
The sample that Anderson carried back to the lab in 1955 contained a type of alga that had not been encountered in the lake before: the cyanobacterium Oscillatoria rubescens--blue-green algae, the classic, tell-tale sign of lake deterioration. To Edmondson, it sounded the alarm that Lake Washington was headed for serious trouble.
Basic research conducted over the years by Edmondson and colleagues provided the foundation for understanding what was happening to Lake Washington and for outlining a remedy. Edmondson had recognized that whenever Oscillatoria appeared, deterioration of water quality would follow. It was a pattern that had been noticed in Western European lakes—lakes that had deteriorated after receiving treated discharges from surrounding population centers, just like Lake Washington. Those pollutants, especially the phosphates they contained, provided a feast for plant organisms in the lake. In a similar effect, lakes around Madison, Wisconsin, had bloomed with different types of blue-green algae.
Seattle had begun the practice of discharging raw sewage into Lake Washington around 1900. In 1926, the city began to create facilities to divert sewage from the lake to a treatment plant on the Duwamish River that discharged into Puget Sound. The last sewer outfall from the city of Seattle was removed from the lake by 1941. But thereafter, it was the growth of the suburbs, not the city, that contributed to the buildup of pollution in the lake. Ten sewage treatment plants were added at various locations around the lake over the period of 1941 to 1953. They had a combined daily effluent of 80 million liters (about 20 million gallons).
Quoted in a Seattle Times article on April 18, 1956 ("Lesson of Switzerland Lakes Brought Home to Seattle Area"), Edmondson explained the problems created by the buildup of pollutants, particularly the problems of enrichment with phosphorus. They serve as nutrients for the growth of plant life, which ultimately would make the water cloudy and smelly, and would interfere with other life.
In what may stand as a model for presenting scientific information to public policy-makers, Edmondson prepared a nine-page, simple summary, in question and answer format, for James Ellis, who was then chairman of Seattle's Metropolitan Problems Advisory Committee. The document listed answers to some 15 questions that would likely be asked in the course of the committee's work: How has Lake Washington changed? What will happen if fertilization continues? Why not poison the algae? Edmondson laid out a nutrient "budget" showing that the mass of algae varied in proportion to the amounts of fertilizing nutrients added to the lake, analyzing causes and effects, using clear reasoning and language without jargon. The information hit its mark.
The next step was to create an infrastructure to address the problem. The Washington State Legislature passed a bill enabling the creation of a metropolitan government, "Metro," with six functions: water supply, sewage and garbage disposal, transportation, comprehensive planning, and park administration. A public referendum to set the wheels in motion went on the ballot in March 1958, but was defeated the first time. A revised proposal, approved on September 9, 1958, won 58% of the vote in Seattle and 67% in the rest of King county.
The approved plan called for the creation of a major trunk sewer to divert all effluents from around the lake. The waste would be treated and discharged deep under Puget Sound, where the tidal action would dilute it and carry it away. It was considered the most costly pollution control effort in the nation at that time.
Three years after Edmondson had sounded the alarm, Metro was created, but it was another five years before the sewage treatment facility at West Point could swing into action. In the meantime, the lake quality took a nose-dive, just as Edmondson had predicted. The October 5, 1963 issue of the Post-Intelligencer called it "Lake Stinko."
As effluents were diverted from waste treatment plants, deterioration slowed, and then stopped by about 1964. By 1965, there were signs that perhaps the lake was on the mend: transparency had improved, as algae and phosphate concentrations dropped.
By 1971, the lake was more transparent than in 1950, and today it is twice as clear, a result that even Edmondson couldn't have predicted. The reason stems from a complex relationship between aquatic organisms. A water creature called Daphnia increased in numbers beginning in about 1976. And since Daphnia's favorite delicacies are small algae, as the numbers of Daphnia increased, the concentration of algae decreased and the lake water improved markedly in clarity.
Daphnia's main predator was a crustacean whose population had diminished in the mid-1960s, probably in response to a change in the fish population. After 1965, the main antagonist was Oscillatoria, which fouled Daphnia's feeding apparatus. By 1975, as pollutants--and Oscillatoria--diminished, Daphnia could thrive and graze on algae once again.
In retrospect, Edmondson observes that his research on lake ecology was the foundation on which later lake clean-up efforts were built: "My work on Lake Washington was designed as basic research aimed at increasing our understanding of the control of productivity and community structure in lakes, just because we want to know about those things. My applications to [the National Science Foundation] for grants never described the work as being done for the purpose of pollution control. However, the information that I was getting and the predictions I had to make for the design of the sampling programs were exactly what was needed to evaluate the practical problem. In other words this was an example in which the results of basic research could be put to immediate application"
It is perhaps ironic that basic research "starts from some interesting condition or observation of a natural phenomenon and has as its goal an explanation of that phenomenon; there is no more specific goal at the beginning," as Edmondson explains. A researcher may start from simple curiosity about the nature of the world and follow wherever that may lead. "Applied research cannot be done effectively without a background of information developed by basic research," he affirms.