Dry Falls Dam, Embankment dam in Grant County, United States

Dry Falls Dam is a rock-faced earthfill dam spanning the midsection of Grand Coulee near Coulee City. It holds back Banks Lake, a 27-mile equalizing reservoir filled by water pumped from the Columbia River through the Feeder Canal. The dam has an impervious central core, semi-pervious layers compacted in one-foot lifts, and rock fill laid in three-foot layers.

The project emerged in the 1940s as part of a broader water management initiative for the Columbia Basin region. The dam was built to meet irrigation demands for agricultural expansion across central Washington.

The dam's original name, South Coulee Dam, was changed to Dry Falls Dam, echoing the nearby Dry Falls of the Grand Coulee. The Main Canal headworks near Coulee City were later expanded with six pump/generating units, and the canal was widened from 50 to 80 feet.

The dam is most accessible from land-based vantage points that provide views of the structure. Visitors should note this is an active work area where access may be restricted to certain zones.

The dam was first called South Coulee Dam; the contract awarded to Roy L. Blair and Company and James Crick and Sons came to $2,771,887, and work started in mid-July 1946. A concrete cutoff wall, 5 to 10 feet high, runs along the dam's length to stop seepage under it.