Columbia River Instream Atlas Project - Final Report

The Columbia River Instream Atlas (CRIA) is a compilation of existing data products and best professional knowledge that provides tools (workbooks, maps, reports, GIS data) to aid in prioritizing stream reaches for flow restoration and augmentation. CRIA provides detailed information for 189 stream reaches in eight fish- and flow-critical watersheds in Eastern Washington: Okanogan, Methow, Wenatchee, Upper Yakima, Naches, Lower Yakima, Walla Walla, and Middle Snake Rivers.

As directed in 90.90 RCW, the Washington Department of Ecology Office of Columbia River (OCR) is developing a 2011 Columbia Basin Long-term Water Supply and Demand Forecast that includes information developed through CRIA. OCR will also use CRIA to aid project funding decisions and water rights determinations as called for in statute.

CRIA brings together data on fish status, distribution, and life history utilization with information on salmonid habitat and flow conditions. An important objective is to make salmonid species and habitat information available to the lay person through interactive map products.

Independent scores for fish status/utilization, habitat condition, and flow condition were generated for each stream reach. The three scoring elements were then combined, for display and interpretation purposes, into a triplet score characterizing each reach. In this way, a broader range of stream reach information is available to the user than would be available under a single-score system.

Using the tools created with this project, it is determined that great opportunity to improve salmonid production exists by pursuing water acquisitions in smaller, lower elevation streams with good to excellent habitat. However, streams with good to excellent habitat in higher elevations or less populous areas should not be overlooked, nor should lower mainstems through which most stocks/species must migrate. Any flow augmentation could be helpful in salmonid restoration efforts, especially in smaller systems that have limited flow, in over-appropriated basins, and/or in combination with other recovery measures.