Flood control measures on Mill Creek include a concrete channel that extends over two miles through the city of Walla Walla. The Mill Creek Barrier Assessment completed in 2009 identified and described barriers for Endangered Species Act (ESA) listed steelhead and bull trout and for reintroduced spring Chinook. Returning adults encounter flow dependent depth and velocity barriers, and a lack of resting opportunities. Juvenile fish encounter low spring flows, and high water temperatures in late spring. Often by mid-May, adults and juveniles become trapped in the flood control channel where they experience lethal temperatures. Many of these passage issues are considered imminent threats in the Snake River Salmon Recovery Plan. The Mill Creek channel upstream of the flood control project is a critical and under-utilized area for spawning and rearing of ESA listed species. Restoring fish passage through the concrete channel allowing access to upper Mill Creek provides an important recovery opportunity for ESA listed fish, as well as good habitat for other native fish and reintroduced spring Chinook. This project will extend the fish passage treatment approximately 919 feet, starting adjacent to McKinley Street east to the upstream end of the concrete channel. After cpmpletion, the upper mile of the two-mile channel will have improved passage.