After digging a little further in to Seattle’s sewage and stormwater systems, I will never see a stream of water running down the street in the same way. I have always wondered, where does that go? We have an old set of pipes beneath the city that carry stormwater from our streets and roofs, and sewage from our homes and businesses. About two thirds of the pipes in the city of Seattle combine both sewage and stormwater for an efficient flow to the West Point Treatment Plant. At this point, I am sure anyone reading this is already bored, but stormwater and even sewage can be an interesting design topic! Just as the Yosemite Falls can inspire and delight, urban design concerning water can also incite delight, and a sense of responsibility.
What better way to disconnect people from natural systems then to hide them underground. Our wastewater infrastructure is a system of the past, a pragmatic approach to dealing with waste and runoff instead of envisioning opportunity. The image above is Sydney Park in Australia. This design has the capacity to collect 200 million gallons of stormwater, filter it, and recirculate it during dry months to maintain an active water feature in a beautiful park/bike-ped transit corridor. 200 million gallons is a lot of water.
The failure of West Point Treatment Plant on February 9th resulted in 300 million gallons of untreated wastewater being dumped in to the Puget Sound. Typically, the plant does a great job in cleaning our wastewater up to 95% cleanliness before discharging in to the Puget Sound. However, in some years depending on the consistency in rainfall, Seattle’s underground pipes can discharge tens to hundreds of millions of gallons per year of combined wastewater due to overflow. This wastewater never makes it to the treatment plant, and instead carries toxic chemicals, fossil fuels, bacteria, metals, and pesticides straight in to where our families swim and boat in the summer time, and where our salmon struggle to re-spawn and contribute to the wonderful biodiversity of the Pacific Northwest which we all care about.
Seattle can do better. Seattle needs to do better. The city and county have released a plan to protect our water ways, yet their approaches are couched in the antiquated thinking that disconnected us from natural processes in the first place. Underground storage tanks and street sweepers that pick up debris are about the most uninspiring solution a city’s leaders could think of. Dealing with blackwater is different than dealing just with stormwater, but performative wetlands and ecological science technologies are financially and socially feasible and arguably more efficient and inexpensive!
Those folks down under understand that taking something as mundane as stormwater and blending it with social and environmental positive impacts, can foster respect and appreciation for the natural world in which we live.