Tri-State Steelheaders used this funding to remove an unused dam in the upper Mill Creek watershed east of Walla Walla, Washington to improve fish passage. In the early 1900s, a concrete diversion dam was built on Mill Creek, near Kooskooskie, for the city's water system. Changes to that system have left the dam unused for over forty years. The dam and adjacent property are now under private ownership. The Kooskooskie Dam was a passage barrier to juveniles and some adults of species that include ESA-listed steelhead and bull trout. The dam prevented free passage to 32 miles of high quality spawning and rearing habitat in the upper Mill Creek watershed. The Washington State Conservation Commission (2001) noted that upper Mill Creek is one of the few remaining refuges for summer steelhead and bull trout in the Walla Walla basin, and identified Kooskooskie Dam as an obstruction on this reach of Mill Creek. The Mill Creek Technical Work Group identified the dam as an impediment to fish production in the Mill Creek basin. Removal of the dam eliminated height and velocity barriers, increasing the availability of the upper Mill Creek watershed to spawning and rearing by steelhead, bull trout, reintroduced spring Chinook, and non-salmonid fish species that provide food for salmonids.