Bioretention was approved over six years ago by the Washington State Department of Ecology for use as a stormwater treatment facility. Yet King County lags behind in accepting it for use. Bioretention is a versatile stormwater management facility and the only known water quality treatment method to address 6PPD, a pollutant that research has linked … Continue reading Salmon Killing Chemicals Can Be Treated with Bioretention, but King County Says No