Derby Dam

Derby Diversion Dam
Aerial view of the dam
LocationStorey / Washoe counties, Nevada
Nearest cityFernley, Nevada
Coordinates39°35′9″N 119°26′49″W / 39.58583°N 119.44694°W / 39.58583; -119.44694
Built1903
MPSNewlands Reclamation TR (AD)
NRHP reference No.78001727
MARKERS No.43
Added to NRHPApril 26, 1978

Derby Dam is a diversion dam built from 1903 to 1905 on the Truckee River, located about 20 miles (32 km) east of Reno in Storey and Washoe counties in Nevada, United States. It diverts water into the Truckee Canal that would otherwise enter Pyramid Lake. The canal feeds Lake Lahontan reservoir in the Carson River watershed, where it is used for irrigation.

It was the first project of the newly organized U.S. Reclamation Service (known today as the U.S. Bureau of Reclamation), organized by the Reclamation Act of 1902.

As a result of the diversion, Winnemucca Lake lost inflow and dried up, and Pyramid Lake lost more than 80 feet (24 m) in elevation, resulting in the near-extinction of the Lahontan cutthroat trout.

The dam is operated by the Truckee-Carson Irrigation District. It was named after the Derby Southern Pacific Railroad station.