Gold Hill Irrigation District Improves Fish Passage At Dam On Rogue River
The Gold Hill Irrigation District operates a diversion dam on the Rogue River near the town of Gold Hill. The diversion dam and canal, which supplies the community with irrigation water, had been virtually unchanged since 1916. Design flaws meant that many migratory fish were diverted along with the irrigation water, ending up in an irrigation canal where they were easy prey for bird and mammal predators.
In partnership with Freeways for Fish, the Gold Hill Irrigation District undertook a major upgrade and restoration project that improved safety for migrating fish at the site. Together, we
- Decreased the amount of water and the number of fish diverted out of the Rogue River without affecting the District’s water right
- Returned diverted fish to the Rogue River quickly by replacing an open ditch with a pipe, eliminating the risk of predation in the canal environment
- Removed a canal overflow area that attracted adult fish away from the Rogue River
Each spring for millennia, downstream-migrating young salmon, steelhead, and Pacific lamprey have been traveling from the upper parts of the Rogue Basin all the way to the Pacific Ocean. In the last few decades, however, many wound up diverted along with irrigation water at the Gold Hill Irrigation District’s diversion structure. For nearly a century, these diverted fish spent days – or weeks – in a ¼-mile long irrigation canal before they could return to the mainstem of the Rogue River.
The water in the irrigation canal was warm and shallow, creating stressful conditions for fish and high rates of predation by birds and mammals. Downstream from the dam, another canal spillway attracted migrating fish away from the river and into a shallow, debris-filled dead end. Away from the protection of the deep, cool Rogue River, these adult fish were also easy prey for large predators.
In August 2014, the Gold Hill Irrigation District initiated construction to replace the open irrigation ditch with a closed pipe. The project has since decreased the number of fish that are diverted into the district’s facilities, moving any fish that do get diverted back into the Rogue River quickly, and eliminating the attraction of the canal bypass area. These improvements have increased the survival of young salmon on their way to the ocean, as well as the number of spawning fish that reach the upper Rogue each year.