Supplement Analysis for the Watershed Management Program EIS (DOE/EIS-0265/SA-67)

BPA is proposing to provide cost share for a program that will protect ESA-listed salmonid species in the Walla Walla River Basin through the installation of Washington Department of Fish and Wildlife (WDFW) and National Marine Fisheries Service (NMFS) approved fish screens on up to 197 irrigation diversions in the basin. ESA-listed steelhead and bull trout are presently at risk in the Walla Walla Basin as the result of a combination of factors that primarily involve insufficient flow, extensive habitat degradation, and mortality from surface water diversions. Unscreened or improperly screened diversions can damage fish scaling and induce stress, both of which can be lethal. They are also known to cause migration delays and increased predation; impinge fish against screen surfaces; or, in cases where screen mesh size is too large, allow juvenile fish to be drawn directly into functioning irrigation systems resulting in direct mortality. The goal of this project is to eliminate imminent mortality risks to ESA-listed fish arising from inadequate irrigation diversions in the Walla Walla Basin by upgrading screens to current state and federal juvenile fish screen standards. This Supplement Analysis covers only those screen upgrades and/or installations that will meet the NMFS no effect standardmore » (NMFS, January 16, 2001). All other screen upgrades and/or installations in the Walla Walla River Basin associated with this project will require additional NEPA analysis and documentation prior to implementation.« less