TMDL image

Water Quality Improvement Projects (TMDLs)

Cowlitz County projects

The following table lists overview information and links to specific water quality improvement projects (including total maximum daily loads, or TMDLs) for this county. Please use links (where available) for more information on a project.

To get additional information about the water bodies in Skagit County please use the Water Quality Assessment Query Tool.


WRIAs in Cowlitz County

  • WRIA 23 - Upper Chehalis
  • WRIA 25 - Grays-Elochoman
  • WRIA 26 - Cowlitz
  • WRIA 27 - Lewis

Water-body Name Pollutants Status TMDL Leads
Chehalis River Basin Upper Chehalis River Watershed
  • Ammonia-N
  • BOD (5-day)
  • Dissolved Oxygen
  • Fecal Coliform
  • Temperature

Approved by EPA

Andrew Kolosseus


Last updated October 2016