Merrick-McLaughlin Whitewater Design Group Design Enhancements Aiding in Recovery of Endangered Native Fish

Colorado – September 13, 2012 – At a recent ribbon cutting ceremony, Merrick-McLaughlin Whitewater Design Group (M-MWDG) was recognized after having provided hydraulic engineering expertise for design of the first known combined state-of-the-art fish passage and recreational whitewater facility in the U.S. The project is located adjacent to an existing diversion dam on the Gunnison River near Delta, Colorado.

Scope of work includes removal of a vertical drop at the dam and design and installation of hydraulically connected but independent channels to enable both fish passage and boat passage. The fish passage facility design allows native Colorado endangered fish the ability to negotiate the diversion dam, thus promoting recovery of these species. The boat passage channel provides a high performance recreational experience for river enthusiasts and boaters.

Owned by the Hartland Irrigation Company, the existing dam was constructed in 1881 as a 6-foot high vertical structure to divert water to their canal. As originally constructed, the vertical dam did not allow upstream and downstream movement of fish while also preventing upstream and downstream navigation by boaters. The irrigation company and the Painted Sky Resource Conservation & Development Council, Inc. (District) wanted these issues resolved and selected M-MWDG to provide engineering services to accomplish this mission.

The project includes an innovative multi-slot baffled fishway that orients weak swimming fish upstream and is hydraulically efficient in allowing passage of target species in a much shorter and less costly channel. This design also reduces debris accumulation and is a much lower hazard to boaters and river enthusiasts. The fish passage facility extends the upstream range of the Colorado native endangered fish by approximately 15 miles which re-establishes and maintains the endangered fish population and, overall, improves the ecosystem health of the river.

M-MWDG served as engineering consultant and provided multi-dimensional computer modeling, hydraulic analysis, alternative evaluation, design engineering, plan preparation, cost estimating, and construction phase support for the project, while working closely with the United State Fish and Wildlife Service (USFWS). The newly combined fish and boat passage facility result in positive social, economic and sustainable design benefits for the State of Colorado.

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