Yakima River RM 153
Off-channel habitat availability is reduced throughout the length of the Yakima River due to diking, road and railroad construction, floodplain gravel mining, and development. In the late 1990s, an enhancement project near Ellensburg (between Yakima River Miles 153 and 154) allowed Yakima River fish to access a 0.6 mile left bank side channel and the lower 8 miles of the Wilson Creek system as off-channel habitat. The project installed a river-spanning rock structure to divert flow into the side channel. The structure was damaged by a combination of factors, and currently requires annual maintenance in order to divert flow. Fish are stranded in the side channel when Yakima River flows drop due to reservoir management. The Bull Canal Company diverts Yakima River water from the side channel. When flow is insufficient in the side channel, they rely on their Wilson Creek water allocation instead. This can significantly decrease flow in Wilson Creek, reducing the quality and quantity of off-channel habitat in this system as well.
Mid-Columbia Fisheries proposes to create a final design for a restoration action to reduce fish mortality in the side channel, increase availability of Yakima River water for Bull Canal Company, and increase availability of off channel habitat. Mid-Columbia Fisheries will assess existing conditions, perform an alternatives analysis, model hydraulic function, perform cultural resource surveys, and produce a final design to SRFB. Designing an appropriate alternative will replace the need for annual maintenance of the rock structure, reduce fish stranding and mortality, and increase water availability for the benefit of irrigators. The selected alternative will improve habitat quality in 8 miles of lower Wilson Creek and reduce fish mortality in the side channel. It will benefit Chinook and Coho salmon, steelhead, Rainbow Trout, and Cutthroat Trout.