Water Quality Improvement Projects (TMDLs) > Yakima Watershed Area Projects > Upper Yakima River Area Multi-parameter Project

Water Quality Improvement Project
Upper Yakima River Area:
Multi-parameter

Water quality issues

Water quality testing found toxic chemicals in the water of the Yakima River and some of its tributaries. Most of these chemicals are banned pesticides or PCBs (polychlorinated biphenyls) that are no longer used.

Past studies show that some of these chemicals get into the water when contaminated soil erodes and enters the water.  Some of these chemicals were also found in fish living in the Yakima River and some of its tributaries.

The upper Yakima River is also on the 303(d) list for water temperature. Monitoring done near Cle Elum and near the Wenatchee National Forest revealed water temperatures that did not meet state water quality standards. (See study map.)

Why this matters

Suspended solids impair fish and aquatic insect respiration. Particles can also settle and clog spawning gravel or suffocate fish eggs.  Suspended sediments can also carry organochlorine pesticides into the water.

The Department of Ecology (Ecology) believes the control of suspended sediment generation and transport during the irrigation season will result in far-reaching water quality and fish habitat improvements in the Yakima Basin.

Water temperature influences what types of organisms can live in a water body. Cooler water can hold more dissolved oxygen that fish and other aquatic life need to breathe. Warmer water holds less dissolved oxygen. Many fish need cold, clean water to survive.

One way to cool water temperature is to shade the water body by adding or retaining streamside vegetation.

Toxic chemicals, which are persistent chemicals in the environment, are a growing concern for the state. They can contaminate the food (fish, shellfish, etc.) that people may eat.  In the Yakima River valley, these chemicals are mostly from agricultural pesticides and industrial pollution. They can be found in our air, water, soil, and wildlife. And, they are showing up in people's bodies, which may lead to health problems.

Turbidity reduces the amount of light penetration in the water, and can interfere with natural productivity in the river. Turbidity also makes it more difficult for fish to move, avoid predators and find food.

Status of the project

Suspended sediment and turbidity

Ecology, along with local interest groups, developed a total maximum daily load (TMDL) report.  The report contained a summary of the results of water quality studies in the upper Yakima watershed, and an implementation strategy that discussed the goals, objectives, and strategies to implement cleanup recommendations in the study.  The TMDL was approved by EPA in September 2002.

Ecology then developed a more detailed implementation plan which laid out the actions needed to address the pollution issues and achieve target loads prescribed in the TMDL.  Ecology sent a copy to EPA in 2003.  A first round of effectiveness monitoring was completed in 2006/07.  The monitoring results showed that TMDL implementation has been successful so far.  Local activities to reduce suspended sediment activities resulted in lower total suspended sediment (TSS) and turbidity values in 2006, compared to 1999. Full compliance with the TMDL is expected to be achieved by 2011.

Temperature

A quality assurance project plan (QAPP) was completed for the project in 2005.  The QAPP describes how the technical study will be conducted to determine the extent of the water temperature issue in the upper Yakima river area. The project is on hold due to staffing issues.

Toxics

Farmers and other land users in the watershed implemented existing TMDLs that may help some of the water quality problems. The Roza Sunnyside Board of Joint Control and Kittitas County Water Purveyors adopted water quality policies that reduce the amount of polluted runoff entering into tributaries of the Yakima River. Many agricultural operations adopted practices that prevent or reduce their impact to streams. Monitoring of DDT, dieldrin, and other chlorinated pesticides continues to measure the progress of other water quality improvement project work to bring the watershed into compliance with state water quality standards.

Ecology conducted a study on water quality conditions in the Yakima River watershed in 2006. Although additional sources of toxic contamination to the surface waters were found, changes in agricultural practices have reduced the amount of pollution coming from irrigation runoff. While some Yakima River fish still have pesticides in their flesh, the levels are much improved (reduced) compared to previous years. This reduction in pesticide levels in fish tissue allowed the Washington Department of Health to drop their advisory on DDT in lower Yakima River fish.

Technical information

Suspended sediment and turbidity

Upper Yakima River Basin Suspended Sediment, Turbidity and Organochlorine Pesticide TMDL Submittal Report (Ecology publication)
www.ecy.wa.gov/biblio/0210047.html

Upper Yakima River Basin Suspended Sediment, Turbidity and Organochlorine Pesticide TMDL – Detailed Implementation Plan (Ecology publication)
www.ecy.wa.gov/biblio/0310058.html

Quality Assurance Project Plan: Suspended Sediment and Turbidity Total Maximum Daily Load Effectiveness-Monitoring Project in the Upper Yakima River Basin April to October 2006 (Ecology Publication)
www.ecy.wa.gov/biblio/0910034.html

Yakima River Basin Suspended Sediment, Turbidity and Organochlorine Pesticide Total Maximum Daily Load Study: Water Quality Effectiveness Monitoring Report (Ecology Publication)
www.ecy.wa.gov/biblio/0910045.html

Temperature

Quality Assurance Project Plan: Upper Yakima Basin Temperature Total Maximum Daily Load Study (Ecology publication)
www.ecy.wa.gov/biblio/0503111.html

Toxics

Quality Assurance Project Plan - Chlorinated Pesticides, PCBs, and Dioxins in Yakima River Fish - 2006: Assessing Progress Toward TMDL Targets and Updating the Fish Consumption Advisory (Ecology Publication)
www.ecy.wa.gov/biblio/0603111.html

Concentrations of 303(d) Listed Metals in the Upper Yakima River (Ecology publication)
www.ecy.wa.gov/biblio/0003024.html

Verifying 303(d) DDT/DDE and Dieldrin Listings for the Upper Yakima River (Ecology publication)
www.ecy.wa.gov/biblio/0003023.html

Upper Yakima River Basin Suspended Sediment and Organochlorine Pesticide Total Maximum Daily Load Evaluation (Ecology publication)
www.ecy.wa.gov/biblio/0203012.html

Chlorinated Pesticides, PCBs, and Dioxins in Yakima River Fish in 2006:  Data Summary and Comparison to Human Health Criteria (Ecology Publication)
www.ecy.wa.gov/biblio/0703036.html

Quality Assurance Project Plan- Yakima River Chlorinated Pesticides, PCBs, Suspended Sediment, and Turbidity Total Maximum Daily Load Study (Ecology Publication)
www.ecy.wa.gov/biblio/0703107.html

Yakima River Pesticides and PCBs Total Maximum Daily Load: Volume 1: Water Quality Study Findings (Ecology Publication)
www.ecy.wa.gov/biblio/1003018.html

Related information

Suspended sediment and turbidity

Focus on Upper Yakima Basin - Restoration plan targets sediments (Ecology publication)
www.ecy.wa.gov/biblio/0110003.html

Temperature

Focus on Water Temperature in the Upper Yakima River Basin (Ecology publication)
www.ecy.wa.gov/biblio/0710008.html

Wenatchee National Forest Water Temperature Total Maximum Daily Load: Technical Report (Ecology publication)
www.ecy.wa.gov/biblio/0310063.html

Toxics

New information available on toxic chemicals in Yakima River (Ecology news release)
www.ecy.wa.gov/news/2010news/2010-088.html

Yakima River Watershed Toxics Study (Ecology Publication)
www.ecy.wa.gov/biblio/0610069.html

Frequently Asked Questions: Yakima River Watershed Toxics Study: Progress Update (Ecology Publication)
www.ecy.wa.gov/biblio/0910088.html

Fish Consumption Advisories for Yakima River (WA Department of Health)
www.doh.wa.gov/ehp/oehas/fish/fishadvisories.htm#yakimariver

WRIA 39: Upper Yakima Watershed Information (Environmental Assessment Program web site)
www.ecy.wa.gov/apps/watersheds/wriapages/39.html

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