Department of Ecology Seeking Public Comment on Water Quality Changes

Posted

The Department of Ecology is seeking public comment on updates to state water quality standards that would set requirements for the levels of oxygen and fine sediment in streams and rivers.

According to Ecology, the changes are meant to help support salmon recovery, specifically salmon eggs and young fish.

“Salmon need cool, clean water to survive,” and Ecology press release said. “That includes enough oxygen and healthy habitat.”

When fine sediment settles on salmon spawning gravel, it can block water flow through the gravel which deprives fish eggs and larvae of oxygen. Currently, the state’s standards do not directly address fine sediment, so Ecology is proposing to clarify what fine sediment protection means.

The draft rule says water bodies “shall not contain fine sediment from anthropogenic sources at levels that cause adverse effects on aquatic life, their reproduction, or habitat.”



Fine sediment is defined as sediment smaller than 2 millimeters.

Changes to oxygen requirements Ecology is proposing include increase the required amount of oxygen in the water from 9.5 mg/L to 10 mg/L for salmon habitat. The draft also includes adding a dissolved oxygen and a dissolved oxygen saturation requirement of 90%, which could be used in lieu of the milligrams per liter measurement.

Dissolved oxygen saturation reflects how much oxygen the water can hold at a given temperature and pressure, and measuring it will help determine the cause of low dissolved oxygen, according to Ecology, “which is most often due to high water temperature and excess nutrients.”

“We need regulatory changes to support the investments tribal, state and local governments are making to restore Washington’s iconic salmon runs,” Ecology’s water quality program manager Vince McGowan said in a press release. “Ensuring salmon have enough oxygen and healthy spawning grounds is crucial to salmon recovery.”

People can provide comments on the draft rulemaking language online, at public hearings or by mail. The deadline for comments is Dec. 16. Public hearings will take place on Dec. 8 and 9 online, and written comments can be mailed to the Department of Ecology Water Quality Program c/o Susan Braley, P.O. BOX 47600 Olympia, WA 98504. Ecology plans to adopt the rules March 9.