King County’s new Vashon treatment plant clears way for valuable shellfish harvests

Thanks to upgrades at King County's Vashon Island treatment plant and construction of the plant's outfall in deeper water, about 160 acres of valuable geoduck clams could now be available for harvest.

The Washington State Department of Health has reclassified commercial shellfish growing beds in the area from "prohibited" to "approved."

The change in designation takes effect immediately, and clears the way for commercial geoduck harvesting to begin later this month.

"The new Vashon Island wastewater treatment plant is not only safeguarding the health of hundreds of Island residents, but it's also making a positive difference in the environment," said King County Executive Ron Sims.

"Protecting public health and improving environmental conditions are King County's most important core values," Sims said.

The new treatment plant came online this spring and is performing exceptionally well.

Improvements to the plant included nearly doubling the length of the outfall pipe, where highly treated wastewater is discharged into Puget Sound. Previously located approximately 1,350 feet offshore, the new outfall is located 2,800 feet offshore, where currents quickly dilute the treated wastewater.

The plant serves about 700 customers. A third of these are commercial or industrial, the rest are residential.

The outfall construction also presented an opportunity to remove 5.3 acres of derelict fishing nets in Colvos Passage, which posed safety risks to divers and marine life.

More information on the Vashon treatment plant is available at http://dnr.metrokc.gov/wtd/vashon/.

People enjoy clean water and a healthy environment because of King County's wastewater treatment program. The county's Wastewater Treatment Division protects public health and water quality by serving 17 cities, 17 local sewer districts and more than 1.4 million residents in King, Snohomish and Pierce counties. Formerly called Metro, the regional clean-water agency now operated by King County has been preventing water pollution for more than 40 years.