WRIA 1 Nooksack Watershed

The Nooksack River in June

The Nooksack River in Northwest Washington. Photo: WA Dept. of Ecology

This is a collection of water availability information for the Nooksack Watershed.


The Nooksack Watershed, also known as WRIA 1, is defined as the area that drains to the Nooksack River, but also includes the Sumas River. It is bounded by Bellingham Bay and the Strait of Georgia on the west and the Cascade Mountains on the east. It lies in the western portion of Whatcom County and small portions of Skagit County.

WRIA 1 Nooksack watershed

The Nooksack River Mainstem is fed by the North, Middle, and South Forks of the Nooksack River. The watershed includes various other streams such as the Lummi River, and Dakota, Fishtrap, Bertrand, TenMile, and Whatcom creeks.

Existing water rights

Water rights have been issued in the Nooksack Watershed for over 100 years, and as a result most water in the watershed is already legally spoken for or “appropriated.”

Instream flow rule

Instream flow rules are an element of water and river management that help maintain healthy ecosystems that support fish, communities, and economies. WRIA 1 has an Instream Flow Rule adopted to preserve the uses and values of individual rivers and streams within the WRIA. 

Go deeper

Find more information about water availability in WRIA 1 including acquiring water, finding existing water rights, and learning more about instream flow rules in our Water Availability Focus Sheet linked below.