Waterways prepared a design alternative analysis for discussion with the JCWC and the landowner with the preferred design alternative consisting of complete dam removal and converting the gravity system to a pumped diversion with fish screen. A rock weir grade control structure was designed immediately upstream of the water intake pipe to help promote scour, and a downstream roughened channel was designed to backwater flow sufficiently for the diversion system. The location of the former dam was replaced with a roughened channel to prevent migration of channel head cuts. Construction of this project was completed in Summer 2020.
Kelley Creek Fish Passage Improvement Project
Client: Johnson Creek Watershed Council
Kelley Creek is a moderate gradient tributary to Johnson Creek that flows from south to north near the boundary between Clackamas and Multnomah Counties. The channel is incised and has been impacted by past land uses which have most likely straightened and ditched the channel to accommodate crossings and local and regional roads, limit flooding, and utilize adjacent areas, including historic floodplain, for agricultural use. Waterways was hired by the Johnson Creek Watershed Council (JCWC) to develop designs and help oversee construction of a fish passage project over an existing dam along Kelley Creek. The project site is located on an approximately 16- acre property that has been owned and managed for multiple generations. The property is primarily residential though the owner does graze cattle and the owner holds a water right for an off-channel pond that is primarily a landscape feature though historically it may have been used to store water for irrigation. Prior to project implementation, water entered the pond through a gravity fed system that consists of the approximately five-foot high diversion dam and intake pipe. This dam presented a total fish passage barrier for all fish species.