| Ullúm Dam | |
| Name Official: | Quebrada de Ullúm Dam |
| Location Map: | Argentina |
| Coordinates: | -31.4748°N -68.6498°W |
| Country: | Argentina |
| Location: | San Juan, Ullúm Department, Province of San Juan |
| Purpose: | Power, water supply |
| Status: | O |
| Construction Began: | 1969 |
| Opening: | 1980 |
| Dam Type: | Embankment, earth and rock-fill |
| Dam Crosses: | San Juan River |
| Dam Length: | 300m (1,000feet) |
| Dam Height: | 53m (174feet) |
| Res Capacity Total: | 440000000m2 |
| Res Surface: | 32km2 |
| Plant Commission: | 1981 |
| Plant Turbines: | 1 x 45 MW Kaplan-type |
| Plant Capacity: | 45 MW |
The Quebrada de Ullúm Dam, or simply Ullúm Dam, is an embankment dam on the San Juan River, just west of San Juan in Ullúm Department of the Province of San Juan, Argentina. It is located at the gorge of the Quebrada de Ullum, upstream from the provincial capital San Juan, and creates a reservoir with an area of, a volume of, and average and maximum depths of 15and, respectively. The reservoir feeds a hydroelectric power station with an installed power capacity of .[1]
The region is arid, with mean annual rainfall below, and is traversed by the rivers, San Juan and Jáchal. The dam is employed to regulate the flow to irrigate about of the Tulum Valley for agriculture, which is the basis of the economy of San Juan. It also allows for recreational and tourist activities.
Work on the dam began in 1969, and the facility was inaugurated on December 3, 1980.