Water Quality Improvement Projects (TMDLs) > WRIA 27 > East Fork Lewis River Area Multi-parameter Project

Water Quality Improvement Project
East Fork Lewis River Area:
Multi-parameter

Introduction

The East Fork Lewis River sub-basin is located in Clark and Skamania Counties, in the southwest corner of the state. It subbasin drains 212 square miles, of which the lower 167 square miles are within Clark County. The upper part of the subbasin is in Skamania County, in the Gifford Pinchot National Forest.  Clark County owns over 700 acres (2.6 square miles) of riparian land throughout much of the lower East Fork Lewis River valley.

The sub-basin includes a couple of small towns, but the majority of the watershed consists of small-acreage private properties. Clark County owns a significant amount of riparian area throughout much of the lower East Fork Lewis River valley, with much of that in large parcels of designated park land.

Water quality issues

The East Fork Lewis River and its tributaries are listed on the 303(d) list of impaired water bodies for high instream temperatures and fecal coliform bacteria problems. Waterbodies placed on the 303(d) list require the preparation of a Total Maximum Daily Load (TMDL) to identify and quantify sources of the impairments and to recommend implementation strategies for reducing point and nonpoint source loads.

Why this matters

Fecal coliform bacteria from human and animal waste can make people sick. Bacteria can get into our waters from untreated or partially treated discharges from wastewater treatment plants, from improperly functioning septic systems, and from livestock, pets and wildlife.

People can help keep bacteria out of the water. Bag and trash dog poop. Check your on-site sewage system to make sure it is maintained and working properly. Fence livestock out of streams and use manure management practices that protect water quality.

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

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

Status of the project

The portion of the East Fork Lewis River subbasin located within Clark County comprises the study area for this TMDL. A TMDL for the remainder of the subbasin, in Skamania County, is being developed in the Gifford Pinchot National Forest study by Ecology. The East Fork Lewis River subbasin has been extensively studied by many groups because of its importance for fish resources and its high potential for salmon recovery.

Project timeline:

• The East Fork Lewis River was selected for a TMDL study in late 2004.
• A peer-reviewed study Quality Assurance Project Plan was completed in May 2005.
• The TMDL advisory group kick-off meeting was held in April 2006.
• Climate, streamflow, ground water, in-stream temperature, percent effective shade, and fecal coliform data were collected between May 2005 and November 2006.
• Ecology described data collection methods and presented data summaries at a March 2007 stakeholder meeting.
• Even before initiation of the TMDL, stakeholders began implementing clean-up activities in the East Fork Lewis River watershed. Using an Ecology grant. Clark Public Utilities completed a riparian restoration project on Lockwood Creek in summer 2008. See Technical Information page for the final project report.
• During the summer of 2008, Ecology analyzed and modeled the fecal coliform data in preparation for developing fecal coliform load allocations in the watershed.
• In March 2009, Ecology presented an overview of the monitoring and modeling results to stakeholders.
• From 2009 through 2011, Ecology will analyze and model temperature data, develop fecal coliform and temperature load allocations, and draft the study report.
• In early 2012, Ecology will begin holding Advisory Committee meetings to determine the control measures that will be incorporated in the water cleanup plan.

Related information

WRIA 27: Lewis Watershed Information (Environmental Assessment Program web site)
www.ecy.wa.gov/apps/watersheds/wriapages/27.html

Technical information

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