Publication Summary

Increased water temperature is one of the leading water-quality problems in Washington. Federal law requires states to identify and clean up the bodies of water that do not meet water-quality standards. With local assistance, the Washington State Department of Ecology (Ecology) will be developing water cleanup plans, also known as Total Maximum Daily Load (TMDL) plans to address the temperature problems.

Increased water temperature is one of the leading water-quality problems in Washington. Federal law requires states to identify and clean up the bodies of water that do not meet water-quality standards. With local assistance, the Washington State Department of Ecology (Ecology) will be developing water cleanup plans, also known as Total Maximum Daily Load (TMDL) plans to address the temperature problems.

This summer, between July 29 and August 15, Ecology will measure stream temperatures in several rivers and streams in the Walla Walla watershed using thermal infrared imaging. The survey area includes the Touchet River from the mouth to just above the city of Dayton and portions of the North Fork Touchet, South Fork Touchet, and Wolf Creek. Yellowhawk Creek and Upper Mill Creek may also be surveyed.

Ecology will contract with Watershed Sciences LLC to fly approximately 100 miles of streams in the watershed by helicopter. The helicopters will be mounted with Thermal Infrared Radiometry (TIR) equipment. This imaging method has also been called Forward Looking Infrared Radiometry (FLIR). The equipment will take infrared photographs of the rivers to provide a visual image of each river′s surface temperatures. Ecology is also placing temperature gauges in the rivers to confirm flight data with field readings. The helicopters will fly no lower than 1,000 feet (the length of about three football fields) and will work between 2 and 5 p.m., when daytime temperatures are highest.