Willamette Basin Total Maximum Daily Loads (TMDLs) -
The Solution

Decades of work and millions of dollars of investment by the State, industry, and cities has reversed some of the worst damage to the Willamette River. Cities and industries began treating wastewater in the 1950s, and treatment has improved steadily since. Flood control reservoirs built by the federal government have increased summer flow, providing waste dilution during this critical period. Today the river is cleaner and healthier than it once was for people and fish. However, there is still much work to be done.

The Oregon Plan is a commitment from Oregons citizens, businesses, agencies and governments to work together to ensure our children will inherit healthy watersheds. The Oregon Plan is people working locally; watershed councils coordinating the work; local landowners and governments initiating new ways of doing things; funding and expertise from state, tribal and federal agencies, and businesses and industries; and implementing existing laws and regulations. Most of all, it is a spirit of volunteerism and stewardship characteristic of Oregon and Oregonians.

Efforts to restore the watershed involve everyone in the watershed. Actions include planting vegetation to reduce erosion and keep water cool; changing habits at home, at work, and at play to prevent or reduce pollutants entering waterways; improving fish passage and opening habitat that was blocked by past practices; and reducing erosion and sediment entering streams. For more information on how to help, view Preventing Surface Water Runoff.

Mercury is another key issue that people can learn more about to reduce its impairment on the environment. DEQ is actively involved in a study to reduce mercury pollution in the Willamette.

TMDLs and Water Quality Management Plans

Oregon is required to establish Total Maximum Daily Loads (TMDLs) for streams segments which do not meet water quality standards. The TMDL identifies the level of pollutants that a water body can absorb and still meet water quality standards. TMDLs take into account pollution from all sources, including discharges from industry and sewage treatment facilities; runoff from farms, forests and urban areas; and natural sources. TMDLs also include a safety margin to account for uncertainty.

This information is then used to determine what changes must take place to achieve water quality standards. The TMDL will be used to determine whether changes are needed for wastewater discharge permits for industries and sewage treatment facilities. Water quality management plans (WQMP) are also developed based on the TMDLs. These plans document the ways that local landowners, agencies, forest and agricultural land managers (including federal agencies), DEQ and others will implement a specific TMDL and work to improve water quality.

More information on the Willamette

• Related Links
• Map: TMDL Development Status for 303(d) Listed Waters PDF
• The Willamette River TMDLs Council
• Willamette Basin TMDLs Fact Sheets and Overview Maps
• June 2004 Assessment and Opportunity Analysis PDF