Hemphill Diversion Structure Fish Passage Project
HEMPHILL DIVERSION FISH PASSAGE PROJECT - Construction in Progress:
First water flows through the new Hemphill fish passage
Ready for salmon and steelhead
(November 15, 2022) The recent rains have brought the Auburn Ravine to life, and the Nevada Irrigation District (NID) has announced the new Hemphill fish passage is now flowing water.
The District’s fish passage construction will open up about six miles of habitat to migrating and resident fish on the Auburn Ravine, northeast of Lincoln.
Salmon and steelhead swim up the ravine every fall and winter. After the recent rains, the flows are 150 cubic feet per second (cfs) through the new passage. That is enough for fish to navigate upstream.
NID’s recent project replaced the Hemphill Diversion Structure that dates back to the 1930s. Since the District purchased the facility in 1933, the eight-foot-tall concrete structure has diverted water from Auburn Ravine into the Hemphill Canal, located south of the ravine, for delivery to NID raw water customers.
The diversion structure, which was a barrier to fish, has been replaced with a system that will allow fish to migrate upstream while also allowing water delivery to customers via the Hemphill Canal.
The District’s passage features a roughen-rock ramp that will allow fish movement in both low- and high-flow conditions. In addition, improvements to the Hemphill Canal include a screen to prevent fish entrapment.
“NID is proud to complete this important project, which will make a difference in the ecosystem and help promote vital species to our region,” said General Manager Jennifer Hanson. “It is a fine example of the District’s commitment to watershed stewardship.”
Of note, NID also completed a fish passage project in 2012 at its Lincoln Gauging Station near the Lincoln Dog Park west of Lincoln Boulevard.
Watch the first flows! Click here to see a short video.