Scholarly Work - Civil Engineering
Permanent URI for this collectionhttps://scholarworks.montana.edu/handle/1/3460
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Item Flow-Control Plates to Manage Denil Fishways in Irrigation Diversions for Upstream Passage of Arctic Grayling(U.S. Fish and Wildlife Service, 2023-06) Plymesser, Kathryn; Blue, Tyler; Kappenman, Kevin M.; Blank, Matthew; Cahoon, Joel; Dockery, DavidSmall-stream irrigation diversions are key elements of many on-farm irrigation systems but can act as barriers to aquatic species. Denil fishways have been installed at irrigation diversion structures throughout the Big Hole River watershed in Montana to provide upstream passage for a population of Arctic Grayling Thymallus arcticus. When stream flows are low and irrigation demand is high, irrigators look for ways to maintain adequate diversion, but doing so may reduce the effectiveness of the fishways. In response, agencies and irrigators have proposed flow-control plates placed at the upstream end of fishways. We conducted laboratory-based fishway efficiency experiments with Arctic Grayling placed in an open-channel flume fitted with a Denil fishway and three flow plates. Of the total 200 fish that we used, the fishway entrance attracted 154 fish and we counted these fish as participants. We operated the fishway under varying flow conditions using three flow-control plate treatments and a control to investigate 1) the extent to which each treatment reduced flow compared to the control, and 2) the extent to which each treatment impacted passage success of Arctic Grayling relative to the control. We measured passage success as the ratio of the number of fish that fully ascended the fishway treatment to the number of participant fish attracted to the fishway treatment. One of the three plates, the Denil slot treatment, showed no evidence of reducing either flow or passage success. Another plate, the standard treatment, showed no evidence of reducing flow but moderate evidence of reducing passage success (P = 0.03). The only treatment to significantly reduce water flow rate was the narrowed Denil slot treatment and there was no evidence this treatment reduced passage in comparison to the control. Over all trials, water flow rate through the Denil fishway had a strong positive influence on fish passage success.Item Swimming Performance of Rainbow Trout and Westslope Cutthroat Trout in an Open-Channel Flume(2020-06) Blank, Matt D.; Kappenman, Kevin M.; Plymesser, Kathryn; Banner, Katharine M.; Cahoon, JoelWe used an open-channel flume to characterize the swimming performance of Rainbow Trout Oncorhynchus mykiss and Westslope Cutthroat Trout Oncorhynchus clarki lewisi ranging nominally in fork length from 15 to 30 cm. With an open-channel flume, we observed volitional swim performance of wild-caught Rainbow Trout and Westslope Cutthroat Trout; the fish were not coerced, prodded, or spooked into action. We also observed the maximum short-duration swim speed of the fish, providing important effective leap or velocity challenge information for the design of intentional barriers. We conducted the experiment with a consistently low water velocity challenge and characterized swim speeds by using weighted least-squares regression, revealing no evidence of a difference in swim speeds between the two species. We estimated the overall average swim speed for Rainbow Trout to be 0.84 m/s (SE = 0.02), with a 95% confidence interval of 0.79–0.89 m/s, and that for Westslope Cutthroat Trout to be 0.84 m/s (SE = 0.03), with a 95% confidence interval of 0.78–0.90 m/s. The maximum swim speeds observed were 2.72 m/s for Rainbow Trout and 3.55 m/s for Westslope Cutthroat Trout. The project results provide new information on the swimming ability of wild Rainbow Trout and Westslope Cutthroat Trout that can be used to improve fish passage or barrier design.Item Hydraulic Analysis at the Interface of the Yellowstone River and the Huntley, Montana Irrigation Diversion Fish Bypass(Montana State University, 2021-11) Johnson, Andrew; Cahoon, Joel; Zale, Al; Plymesser, Katey; Blank, MatthewThe nature-like bypass channel built to allow fish to circumvent the Huntley Diversion Dam on the Yellowstone River was constructed in 2015. A project was commissioned in 2019 to determine the effectiveness of the bypass using hydraulic modeling and fish detection techniques. During the course of the study it was observed that there may be a localized zone of high water velocity at the interface between the upstream end of the bypass and the main channel of the river -an area just upstream of the low-head dam. The concern this raises is that some fish that successfully negotiate the bypass channel may be returned directly over the dam due a difficult hydraulic condition at the interface. That observation prompted a more focused hydraulic modeling exercise as reported herein. A detailed 2-D HEC-RAS model was developed to investigate the hydraulic conditions. The model predicts localized water velocities of up to 15 ft/sec. At low river flows there appears to be adequate pathways for fish to avoid this high velocity region, but as river flow increases so does the area in which the velocity is high. From these results it is likely that, during higher river flow periods, the bypass channel may be passable, but fish may struggle to re-enter the river channel successfully. Suggested physical alterations to the site to help overcome this range from the addition of large rip rap to rerouting the upstream end of the bypass channel. Acknowledgement