Rainy Storms Pump Sewage Into Puget Sound
Combined sewer overflow (CSO) photo courtesy of Seattle Public Utilities
It’s raining in Seattle. (Surprise!) In fact, it’s pouring. Forecasters are predicting up to 2 inches of rain today, and it won’t be stopping anytime soon. So where does all that water go?
Big storms like these increase the chances of sewage overflowing into Puget Sound, thanks to Seattle’s combined sewer system. According to Seattle Public Utilities, about two-thirds of the city uses combined or partially combined sewer system, meaning that both stormwater from the streets and wastewater from our homes go through the same pipes. On a normal day, the combined water goes to a treatment plant to be cleaned of pollutants and waste. But during heavy rains, the increase in stormwater can cause the combined sewer system to overflow, and the excess water gets dumped into Puget Sound. These combined sewer overflows (CSOs) contain both street runoff (90%) and raw sewage (10%). In 2011, SPU reported 666 million gallons of untreated CSO water from Seattle was released into Puget Sound. That’s a lot of pollution.
To mitigate this problem, the City of Seattle is building large water tanks to hold excess water during storms. After each storm ends, the tanks slowly drain to send water to a treatment facility. At the Murray Pump Station in West Seattle, the design process for a new water tank is already underway. The Murray station normally discharges 5 million gallons of untreated CSO water per year, but with the new 1 million gallon tank that number should decrease dramatically.
Community mural painting party at Lowman Beach Park
At Nature Consortium, we’re really excited for the new tank to be built. It’s one more step towards cleaning up our beloved Northwest environment. But construction can be an eyesore in a residential community like West Seattle. To help prepare the community for the three years of construction ahead, we worked with Seattle Public Utilities and local neighbors to create a 16-panel mural to surround the construction site.
After a great community mural painting party back in July, the new mural is up and adds a burst of color to the otherwise drab construction site. It’s just one way that Nature Consortium and the City of Seattle combine art with environmental action.
Learn More
– Murray CSO control project
– City of Seattle sewage overflow prevention
– How you can help (via Seattle Times)
– CSO control program 2011 report
– Take Winter By Storm weather preparedness
– Adopt a storm drain
[…] Lubbock is the dwelling site of eleven water towers. They stand ignored everyday. Obtain further adv…ance to run all the systems in society, these water tanks were built. One of the tanks was an external freestanding pipe that was no longer used. The really big ones that glisten in the sun and blink with red warning lights to the aircraft, at night are about the only ones in Lubbock which directly affect the city. The pressure in the distribution pipes should be maintained at a steady level and this is a role performed by the water tanks. Lubbock's water treatment supervisor shared that each of these water tanks is able to store a million gallons of water. The level of water is maintained through controls at the main office of the Municipal Water Plant. Lubbock has a number of reservoirs located all around the city and water channels are used to distribute water throughout the city. Before these water towers were introduced, Lubbock got by with the use of vertical standpipes. It still holds water so it won't blow down in strong winds says. More information on the topic of water tanks is located at underground water tanks. The role of maintaining pressure in the water lines was given to the water towers instead of the standpipes. The old tanks which no longer serve a particular purpose would be demolished and its individual parts would be sold as scrap metal. One of the old water tanks has been turned into one that stores treated water to fuel the main station's boiler rooms and airconditioning systems. The interior of the tanks are lubricated with protective grease. The development of rust is an issue with these tanks that is why an electrical field is preserved in the water. The water tanks are looked after by an out of state firm contracted by the city of Lubbock. All three of these tanks are checked periodically for any sign of failing equipment or deterioration then repaired accordingly. Eruption of the tanks is not likely. The excess water just flows out an overflow outlet on the side of the tank, down a pipe and into the ground. In the control room, a signal lights when the water pressure in the tank is excessive and if the demand for water is lacking. They immediately cut back the pumps at the pumping station in that area. These gigantic towers, whether proven useful or not, serves to provide Lubbock a view different from the boring plains and numerous telephone poles. A number of these tanks have been present ever since the city was born. The water system's function is greatly affected by these water tanks as they are responsible for supplying the population with water. Whether an obsolete steam engine or a thirsty employee, each tank offers the water needed to survive. […]