On July 20, 1961, the Municipality of Metropolitan Seattle (Metro) marks the groundbreaking for its Renton Treatment Plant with a parade through the "Metro Subway" (a tunnel made from nine-foot-diameter sewer pipes). Scheduled for completion in 1965, the plant is part of a regional network of sewage-treatment plants and pipelines designed by the engineering firm Brown and Caldwell for the Seattle metropolitan area. It will serve the eastern and southern portions of the Metro service area, taking treated and untreated sewage out of Lake Washington, Lake Sammamish, and the Green River. After receiving secondary treatment, the liquid effluent will be discharged into the Green River, just above the Duwamish River confluence. Solids will be piped to the West Point Treatment Plant for discharge into Puget Sound. In the 1980s the plant will be expanded and its liquid effluent diverted to a pipeline to discharge it into Puget Sound at Duwamish Head to protect the river's water quality, which will improve almost immediately. The sludge will then be handled onsite, rather than sending it to West Point.
Comprehensive Sewerage Plan
For decades sewage and industrial wastes threatened the health of King County's waterways, but a plethora of jurisdictions, including cities and sewer districts, could not find a way to coordinate their efforts to manage wastewater. Public apathy also made it difficult to deal with the issue. Waterways, like much of the environment, were not valued for their ecological systems or as community amenities as much they were seen as resources that could be used to serve commercial and industrial functions.
After World War II, when conditions had deteriorated significantly due to population growth and unfettered industrial and sewage discharges, public attitudes and government regulations began to set higher expectations for waterway protection. All levels of government started to work on improving the situation. In King County, this led to the formation of the Metropolitan Problems Advisory Committee. The committee, made up of citizens from across the county and led by Jim Ellis (b. 1921), presented a plan for addressing the wastewater problem regionally. The committee helped draft state legislation to enable the formation of metropolitan municipal corporations to address issues such as sewage disposal or comprehensive planning.
The bill was passed by the legislature in 1957 and the following year a measure for the formation of the Municipality of Metropolitan Seattle (Metro) to deal with the sewage-disposal problem was put before the voters. It took two tries before voters approved Metro in September 1958. The agency had its first meeting in October and adopted Brown and Caldwell's comprehensive sewerage plan in April 1959.
The plan called for two main treatment plants, one at West Point in Magnolia (then the site of the U.S. Army's Fort Lawton, later the city's Discovery Park) and one at Renton, and a handful of smaller ones to serve topographically isolated areas. A network of sewer lines served neighborhoods and fed into interceptor pipelines, the larger pipes that carried sewage to trunk lines, the very large pipes that carried wastewater to treatment plants.
The west and north sides of Lake Washington, extending to the county line, and a small portion of Snohomish County would drain to the North Trunk line and out to West Point. The east side of Lake Washington and the Green River Valley would be served by the Renton Treatment Plant, where sewage would receive secondary treatment because of regulations for effluent discharged into rivers rather than saltwater. The liquid effluent, with almost all solids removed and having been disinfected with chlorine, would be released into the Duwamish River and the sludge sent to West Point for discharge into Puget Sound until 1970, when a biosolids recycling program started.
Renton Treatment Plant
Renton was chosen for the treatment-plant site because of its location at the divide between the Lake Washington basin and the Green River basin. Before humans interfered with the region's hydrology, Lake Washington drained to the south, via the Black and Duwamish rivers. The Green River Valley drains to the north and becomes the Duwamish just past Renton. Water could drain to the treatment plant there easily and then discharge into the Green-Duwamish River and be carried to Puget Sound, where it would be diluted and dispersed.
Metro acquired a tract of land previously owned by the Great Northern Railway and the Earlington Golf Course. The golf course, established in 1913 by the Town and Country Club, became a public course in 1961 and continued to operate until 1981. The plant only occupied its unused driving range, so it did not interfere with the course itself.
Once a permit was granted by the state Pollution Control Commission (precursor to the Department of Ecology), work could move forward. The start of work on the first treatment plant and first large project undertaken by Metro was marked with quite an event. Staff members organized a day of activities on July 20, 1961, to highlight the enormous scale of the facility and its network of pipelines and to emphasize the forward-looking aspects of the project.
For the Welfare of the Youngsters
The festivities included officials from King County and regional cities, kids from the 14 towns to be incorporated into the sewerage plan, and a drive through the "Metro Subway." The mayors of the 14 cities involved in Metro rode to the event through a tunnel made of nine-foot sewer pipes that were on site in preparation for installation. The children, from those towns' Boy Scouts, Girls Scouts, and Campfire Girls groups, formed human pyramids and other feats in the pipes. There is no mention of the public attending the event in the archived records, nor in The Seattle Times coverage of the event. It appears to have been carried out largely for the benefit of government officials and the press.
The first car through the "subway" tunnel carried speakers for the event: Frank Aliment, mayor of Renton; C. Carey Donworth, chair of the Metro Council; Seattle Mayor Gordon S. Clinton (1920-2011); Byron Baggaley (1911-1997), mayor of Kirkland and representative of smaller cities on the Metro Council; and County Commissioner Ed Munro (1905-1987). Each gave short remarks on the importance of Metro's work. In a press release, Donworth was quoted as saying "the youngsters are being included in the program as a reminder that Metro's true goal is not measured in sewer lines and treatment plants but in providing clean, safe recreational waters for the children and adults of the community" ("Metro Ground-Breaking").
In a memorandum to participants, Bob Hillis, public-information director for Metro, wrote, "The purpose of the youth group demonstrations is three-fold: (a) to provide interesting general and local pictures; (b) to illustrate the huge size of the nine-foot pipe; and most important: (c) to remind all the people seeing the newspaper and television coverage that the welfare of the youngsters is the important purpose of the Metro program" (Memorandum). Though the newspaper does not report on this, the records say the plan was to have one of the girls participating in the pipeline antics do the actual groundbreaking by operating the controls of a clamshell bucket.
The most successful group of scouts or Campfire Girls was to take home a new 50-star American flag as a prize. Hawaii had just recently been added to the union, so the new flags were quite a novelty.
The Renton Treatment Plant, also known as the East Division Reclamation Plant (and later as the South Treatment Plant) would be dedicated almost exactly four years later, on July 22, 1965. It treated an average of 24 million gallons per day of wastewater. It neared its capacity of 144 million gallons per day in the late 1970s and work began to expand the plant. At that point, the treated effluent was having a significant impact on the river, forming up to 25 percent of the river's flow during the dry summer months, and it was diverted to Puget Sound via a pipeline to Duwamish Head (the northern tip of West Seattle) that was completed in March 1987.