At approximately 2 a.m. on February 9, 2017, an equipment shutdown at Seattle’s West Point wastewater treatment plant forced the facility to dump millions of gallons of untreated sewage into the Puget Sound to prevent backflow from destroying more equipment. The wastewater – 10 to 20 percent of which was untreated sewage – was pumped into the Puget Sound at a rate of 440 million gallons every 24 hours through an outflow located about three-quarters of a mile offshore.
Staff at the plant responded quickly to the equipment failure but were unable to restart the 2,250-horsepower motors on the pumps. As a result, water levels in the plant began to rise, prompting staff to stop pumps bringing incoming flow in order to protect the plant. This led to an upstream buildup of sewage which triggered the opening of an emergency bypass gate designed to redirect sewage to the outflow in the Puget Sound. Despite efforts to save the plant “Cavernous rooms filled with pumps and other equipment were flooded to the ceiling and steeped in muck.” King County has a $250 million insurance policy which is expected to cover the cost of all repairs for the 50-year-old water treatment plant. While the exact cause of the failure remains unknown, it occurred during heavy rains and high tide.
Following the spill, the plant has been operating at half capacity. Therefore, during heavy rains, the plant is forced to dump wastewater into the Puget Sound at a rate of up to 50 million gallons per day and divert another 150 million gallons to other treatment plants in the system. Additionally, beaches in Discovery Park, Golden Gardens, Indianola Park, and Fay Bainbridge Park remain closed due to possible water contamination with no planned date for reopening. Just over a week after the spill, the Puget Sound faced another sewage spill when a downed utility poll knocked out power to the 63rd Avenue Wastewater Pump Station near Alki on February 17. Power was quickly restored but not before 300,000 gallons of stormwater and sewage spilled into the Puget Sound.
Sources and Further Reading:
- ‘Major Emergency’ Dumps Millions of Gallons of Raw Sewage into Puget Sound – Komo News
- Officials Say Damage to Sewage Plant in Discovery Park is Catastrophic – The Seattle Times
- ‘Emergency’ at Seattle Wastewater Plant Dumping Raw Sewage into Puget Sound – King5
- Crippled Treatment Plant Continues to Dump Raw Sewage into Puget Sound – The Seattle Times
- Beaches Closed after Leak Dumps Untreated Sewage into Puget Sound – Kiro 7
- Another Sewage Spill Fouls Puget Sound, This Time in West Seattle – The Seattle Times
- Power Outage Causes Pump Station to Dump 300,000 of Sewage and Stormwater into Puget Sound – Komo News