Willamette Basin Total Maximum Daily Loads (TMDLs) -
Technical Data

• Temperature Guidance
• Heat Source

Water Quality Studies

The Oregon Department of Environmental Quality began investigating the status of the health of the Willamette River in the early 1990's.

  Reports on the results of five years of study:

• Characterization of Bacteria Concentrations at Water Recreation Sites in the Middle Willamette River, July 1999 PDF
  • Appendicies PDF
• Characterization of Skeletal Deformities in Three Species of Juvenile Fish From the Willamette River Basin, February 2000 PDF
• Bioassay for Fish Embryo Development, September 2000 PDF 4.9mb
• Human Health Risk Assessment of Chemical Contaminants in Four Fish Species, November 2000 PDF 2.2mb
  • Appendicies PDF

This investigation prompted Governor Kitzhaber in 1996 to convene a valley-wide "Willamette River Basin Task Force" to analyze the results of DEQ's Willamette Study. In December of 1997, the Governor's Willamette Task Force produced it's List of Recommendations to preserve and protect the river.

• Willamette River Water Quality Study Background
• Water Quality Reports List 1992-1995
• Willamette River Basin Task Force Recommendations Executive Summary

Willamette Basin Mercury Studies

• Quality Assurance Project Plan for the Willamette Basin Mercury Study
• Mercury Food Web Model PDF