South Skagit Bay assessment

There are many freshwater streams and creeks that drain into South Skagit Bay, where shellfish farming takes place. Since 2017, Ecology has worked to discover where and why some of these creeks are sending high levels of bacteria into South Skagit Bay. We do this work to keep shellfish safe for people to eat, and to ensure  water is safe for people to swim and boat in.

Several shellfish beds in South Skagit Bay were downgraded to “threatened” in 2017 by the Washington Department of Health (Health). Some of the beds have elevated bacteria levels, which means people who eat shellfish have an increased risk of illness.

To improve water quality in South Skagit Bay, both Ecology and Health's Shellfish Division identified South Skagit Bay as a priority area for outreach and technical assistance. Taking action now to reduce pollution sources to the bay will help keep people safe, keep shellfish beds open, and ensure harvests from the bay are safe for people to eat.

Common sources of bacteria include pet waste, leaking septic systems, livestock manure, and wildlife.

Map of Sampling Locations

Visit the full interactive map for all of the features and to get our data. Visit the WSDA interactive map for data collected by all of our partners.

Identifying pollution sources 

To help the local community identify where and how to reduce bacteria levels, we are monitoring the Big Ditch/Maddox Slough and "Old Stillaguamish" watersheds in South Skagit Bay. To improve water quality, Ecology is focusing on four major elements:

We want to work with you

High bacteria levels in water can cause shellfish bed closures because people can get sick from eating contaminated shellfish. If bacteria levels worsen in South Skagit Bay, up to 2,260 acres of shellfish beds could be closed to harvesting.  We look forward to working with you to prevent a closure of shellfish beds in South Skagit Bay and ensuring access to safe and clean local waters for your family and generations to come.