King County’s biosolids management program earns highest national ranking

King County’s Wastewater Treatment Division recently earned the National Biosolids Partnership’s prestigious Platinum Level status for its biosolids environmental management system (EMS) program.

Biosolids are the nutrient-rich organic byproduct of the wastewater process that the county recycles as a soil amendment.

King County’s EMS program documents, monitors and optimizes the management of wastewater solids and biosolids to meet or exceed regulations that protect public health and the environment.  

King County is one of only 12 public agencies in the nation to attain the Platinum Level status, which represents the highest achievement of biosolids management and environmental stewardship.

“Attaining Platinum Level status is a significant accomplishment, but more than that, it’s a vote of confidence in our program and the high quality of biosolids we produce,” said King County Executive Ron Sims. “This program also helps King County manage its wastewater byproducts in a way that also supports our overall environmental protection efforts.”

Demand for King County’s biosolids has increased, particularly among farmers who grow wheat and canola using biosolids to improve soil quality and add important nutrients, in addition to boosting soil water-holding capacity and reducing topsoil runoff.

Sims acknowledged the role of King County partners who use biosolids in the program’s overall success. These partners include the Boulder Park Soil Improvement Project in Douglas County; Natural Selection Farms in Yakima County; Hancock Forest Management, Inc. in King County; the state Department of Natural Resources, RAMCO, which applies biosolids to the Hancock Snoqualmie Forest and on various state forestlands; and GroCo, which has been using King County’s biosolids since the 1970s to produce a popular Class A compost.

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.