Our crews are on the job 24/7, 365 days a year to ensure the region’s wastewater treatment service – and that remains true as we move into the rainy season. Workers are ready to respond around the clock and work hard to be well-prepared for stormy weather or an emergency.
To make sure we’re ready for what wet weather can bring, we have inspected and replaced equipment, updated control systems, and increased training in a continual effort to make sewer operations more resilient during storms.
Operation crews have conducted annual wet weather refresher training, mechanical and electrical teams have inspected the pumps at offsite stations, and the instrumentation and electrical teams have fine-tuned alarm systems.
All 47 pump stations throughout the wastewater service area have been inspected, and back-up power generators have been tested, fueled, and are ready to provide power in case of an outage. Instrumentation upgrades and pump rebuilds were made at key pump stations to ensure performance and capacity.
Throughout the year, our staff trains for on-call readiness for wet weather that can sometimes stress the wastewater system. Within Seattle city limits, the system is a combined one, where stormwater drains carry water to the West Point Treatment Plant to be processed with wastewater from households and businesses. That means when it rains, as much as 80% of the flow passing through the plant can be stormwater.
King County has made significant upgrades at West Point, including increased plant safety system testing, additional staffing, updating protocols, and regular training on how to respond in emergency situations.
Older equipment has been replaced to increase reliability of operations during high flows. Hydraulic power systems have been installed to improve reliability and resiliency of backup operations. Crews installed a system that keeps short power sags from affecting pump operation and has a new system to automatically switch power sources.
Work continues on a battery uninterruptible power supply project to provide West Point with more reliable power. We also continue to work with Seattle City Light (SCL) to improve the power quality delivered to West Point and have implemented an interim solution that has proven to reduce the impact of power sags that can cause equipment shutdown. SCL has isolated a power transformer so it feeds the plant exclusively, protecting the plant from power disturbances that could occur on other portions of the SCL power system.
In addition to those power projects, over the next 10 years, King County will invest more than $660 million at West Point to protect worker and public safety, the environment, and ratepayer investments through improving system reliability and increasing efficiency.
King County has made tremendous investments in wet weather infrastructure in recent years and continues to invest in wet weather treatment stations. Ongoing and newly completed projects will help control the overflow of stormwater and sewage during heavy rains. King County operates four wet weather treatment stations and is building one in Georgetown that is expected to come online in 2022.