Washington State Department of Ecology

Chehalis Basin Partnership - Lower Chehalis/Upper Chehalis (WRIAs 22/23)

WRIA 22

WRIA 23

Grants awarded through June 2010

$1,939,039

Projected grants July 2010 - June 2011

$62,500

Background

The boards of commissioners from Grays Harbor, Lewis, Mason, and Thurston counties adopted the Chehalis Watershed Plan in May 2004. The planning group started their Phase 4 implementation work in October 2005, and approved their detailed implementation plan in October 2006. Key recommendations in the implementation plan include developing a water data management system, increasing compliance efforts toward illegal water users, and adding incentives for water conservation and reclamation.

The Chehalis Basin Partnership started a Geographic Information System Clearinghouse through Grays Harbor College. The system integrates water quality and other natural resource data and information for the entire watershed. An expanded water quality monitoring program was launched with funds appropriated by the Legislature. The Confederated Tribes of the Chehalis Reservation currently monitors 93 sites throughout the basin, and Grays Harbor College manages and analyzes the data. The Chehalis Basin Partnership has established a yearly watershed festival, mapped water rights in the Skookumchuck sub-basin, and is working towards a hydrologic model of the entire watershed.

Instream flow status

Instream flows were set in 1976 (Chapter 173-522 WAC).

The Chehalis Basin Partnership reviewed existing instream flows. Their findings, based on technical studies and existing data, were that low-flow conditions may be a concern in many streams and rivers in the Chehalis Basin. Data show that stream flows are not met many days from July through October. The partnership recommended retaining current instream flows and regular monitoring stream flows. At this time, Ecology does not intend to propose amendments to the existing flow rule.