The Henry’s Fork Foundation (HFF), Conant Creek Canal Company, and Fremont-Madison Irrigation District are partnering on a project that was awarded $1.1 million from the USBR WaterSMART Water and Energy Efficiency Grant Program in 2022. The project aims to conserve water, and improve efficiency and precision of delivery to water users in eastern Idaho.
The project will line 5.7 miles of Conant Creek Canal with high-density polyethylene liner, add head gate remote control for more precise management, change the point of diversion, and use flow meters to monitor water conserved. This project, in conjunction with on-the-farm Natural Resource Conservation Service (NRCS) water savings projects being simultaneously implemented on land under the Conant Creek Canal Company, is estimated to eliminate 2,850 ac-ft/year in canal seepage and increase flows in Conant Creek by 13 cfs (~ 39% increase during irrigation season); improving aquatic conditions for cold-water species in both Conant Creek, Fall River, and the Henry’s Fork River.
A portion of the water conserved will be used as a buffer to avoid interruptions in irrigation supply in low water years, and the remainder will stay in Conant Creek. From a fisheries perspective, the water conserved by this project will increase flows in Conant Creek and Fall River during irrigation season, which will help reduce solar loading, effectively decreasing water temperatures in these reaches. Additionally, water conserved will increase storage water in Island Park Reservoir in late summer and early fall. As the crux of the Henry’s Fork fisheries, Island Park Reservoir water supply can make a significant difference for fishery health and the fishing experience.
Increasing storage water in Island Park Reservoir in the late summer and early fall will help support the health of the reservoir, and will provide a supply of cool, oxygenated water to the reach of the Henry’s Fork below the reservoir as well as thermal refuge for cold-water aquatic species.
This project is anticipated to begin in Fall 2022 and be completed by Spring 2023. Conant Creek is located roughly 5 miles southeast of Ashton and originates in the Teton Mountain Range near the Idaho-Wyoming border where it flows roughly 31 miles west before flowing into Fall River.
The Henry’s Fork Foundation will build on its field measurements of the Conant Creek Canal system by researching and selecting a site to install a sonde with probes installed to record pressure (depth), temperature, dissolved oxygen, conductivity, chlorophyll, and blue-green algae. The sonde will be located between the Conant Creek Canal diversion and the canal spillback site six miles downstream. After selecting the site, HFF staff will use an ADCP (acoustic doppler current profiler) to take up to seven stream flow measurements each year and use the information to build a stream flow rating curve for the site. Building on the monitoring and information base, a temperature and pressure logger will also be installed very near the mouth of Conant Creek on Fall River. A rating curve utilizing the same ADCP process will be established at this site. Canal flow measurements utilizing the ADCP unit will also be obtained each time the HFF staff collect stream flow measurements on Conant Creek. This schedule will start in 2022 and continue through the life of the program for a minimum of five additional years although the stage recorders within the canal diversion and spillback will eventually take the place of ADCP measurements for the canal.
Stay tuned for more updates on this project.