The Walla Walla and Snake Rivers are important natural resources for the surrounding communities and serve both the economic and recreational needs of the people in the area. They are important habitats for native fish such as Chinook salmon and rainbow trout and are also both tributaries to the Columbia River.
Due to historically poor water quality, the Washington Department of Ecology (DOE), under Chapter 173-532 of the Washington Administrative Code (WAC), established the Walla Walla Watershed Management Partnership, a group consisting of local stakeholders (such as local tribal governments, city and county governments, and local conservation districts) interested in improving the water quality of the Walla Walla River, who would, in turn, implement the Walla Walla Watershed Initiative.
The Partnership incorporates local management with state oversight to provide a primary governance structure that will protect both local and statewide interests. The goal of their initiative is to improve water quality and to increase water flows to suitable levels for fish while at the same time providing flexibility for all water users. Since the inception of this program, water quality has improved somewhat and flows have increased but much work still needs to be done.
In the past, there was widespread contamination of the Snake River by agricultural pesticides and potential chlorinated dioxin/furan contamination from the Potlatch pulp mill in Idaho (see indicator 3.1.4 for additional information). Since then, however, the water quality has improved significantly and those contaminants have decreased. Currently, the Snake River is managed under Chapter 173-564 of the WAC. The main goal of the management program for the Snake River includes improving water flow to levels adequate for chinook and sockeye salmon runs.
To be effective stewards of the Walla Walla and Snake Rivers, community members must work collaboratively to continue to improve water flow, remove pollutants, prevent further contamination, and establish protections ensuring the rivers' enjoyment by generations to come. Additionally, these things must be done to ensure a healthy ecosystem in which native plants and animals - that depend on these rivers - can thrive. Monitoring water quality is necessary to accomplish those goals as it gives an annual report card of the quality of the waters in the two rivers, thereby "grading" any efforts aimed at improving the rivers' health.
About the Water Quality Index (WQI): The WQI is a complex measure of quality in Washington State's surface bodies of water and ranges from 1 to 100, with 100 representing excellent water quality. Based on components such as temperature, pH levels, fecal coliform bacteria, and dissolved oxygen, the WQI expresses results relative to levels required to maintain uses based on criteria specified in WAC 173-201A. For nutrient and sediment measures, where standards are not specific, results are expressed relative to expected conditions in a given eco-region. Multiple components, monitored monthly, are combined, and results aggregated overtime to produce a single score for each sample station.
This indicator measures the Overall Water Quality (WQI) of the Walla Walla River and the Snake River. According to the Washington State Department of Ecology, the water quality measuring station on the Walla Walla River is located “approximately three river miles upstream from U.S. Hwy. 12” while the Snake River is measured near Pasco “on U.S. Hwy. 12 near Burbank at Hood Park.”