Hartland Dam/Gunnison River Enhancements Aid in the Recovery of Endangered Native Fish and Provide
The McLaughlin Whitewater Design Group (MWDG – a division of Merrick and Company) is one of six firms to receive the 2013 Engineering Excellence Awards from the American Council of Engineering Companies, Colorado for the “Hartland Dam Fish & Boat Passage Facilities in Delta, Colorado.” These awards ‘acknowledge the significant role ACEC/CO member firms represent in creating safe, sustainable infrastructure that enhances quality of life in Colorado and across the globe.’
MWDG provided hydraulic engineering expertise for the design of the first combined fish passage and recreational whitewater facility that utilizes state-of-the-art fish passage elements developed by the Bureau of Reclamation. The fish passage facility provides native Colorado, endangered fish the ability to negotiate around the diversion dam, thus promoting the recovery of the species. Half of the existing dam was replaced with three integrated passages, two roughened fish passages and one boat passage, that re-connects fish to 15 miles of river previously obstructed by the Hartland Dam and allows river recreationalists to float downstream from upper reaches, through the dam, to the town of Delta.
Once the river was diverted it became clear that the portion of the dam to remain was in disrepair and needed to be modified to ensure reliable diversion of water into the Hartland Ditch. Sloped grouted boulders were placed at the face of the dam for stabilization and to reduce the hazard created by a reverse roller hydraulic. An integrated low hazard passage route for kayakers and rafters provides continuous resting pools for fish and interconnection between the two different types of fish passages and increase attraction flows. The complex hydraulic analysis needed to balance flow between these three distinct yet continuously integrated passage routes was accomplished using 2-dimensional hydraulic modeling which modeled over 110 individual articulated boulders. Field testing verified that this “roughened channel passage” met the strict criteria of limiting velocities to 4 feet/second while maintaining 2 feet of depth – impressive criteria for any formal fish passage considering the slope of 3.5%.
By restoring the river for fish, increasing river recreation, reducing existing hazards and ensuring a reliable water diversion this project exemplifies achievement of a many goals simultaneously – the future of river projects.
To read more about the award given to MWDG and other engineering firms in Colorado this year, click here.
