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Watershed Planning photo identifier

Watershed Management

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

This page is being maintained as an archive of past information and will not be updated.

link to all WRIAs link to WRIA 24 link to WRIA 23 link to WRIA 14 link to WRIA 16 link to WRIA 21 Map of WRIA 22, Lower Chehalis











link to WRIA 11 link to WRIA 13 link to WRIA 14 link to WRIA 22 link to WRIA 24 link to WRIA 25 link to WRIA 26 link to all WRIAs Map of WRIA 23, Upper Chehalis











Grant funds expended and/or projected through June 2015



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.

Outside links, publications, studies, data


Please send additions or corrections to Chris Anderson, (360) 407-6634.




Plan Website - Chehalis Basin Partnership

WRIA 22 and 23 Status

  • Optional elements: Water quality, instream flows, habitat.
  • Currently in Phase 4: Implementation.