| Cotter Dam | |
|---|---|
 Cotter Dam, 2013 | |
  Location of the Cotter Dam in the ACT | |
| Location | Australian Capital Territory, Australia |
| Coordinates | 35°19′10″S 148°56′19″E / 35.31955°S 148.93853°E |
| Purpose | Potable water supply |
| Status | Operational |
| Opening date | 1912; 2013 |
| Owner(s) | Icon Water |
| Dam and spillways | |
| Type of dam | Gravity dam |
| Impounds | Cotter River |
| Height | 87 m (285 ft) |
| Length | 330 m (1,080 ft) |
| Elevation at crest | 550.8 m (1,807 ft) AHD |
| Dam volume | 380×103 m3 (13×106 cu ft) |
| Spillways | 1 |
| Spillway type | Uncontrolled |
| Spillway capacity | 5,670 m3/s (200,000 cu ft/s) |
| Reservoir | |
| Creates | Cotter Reservoir |
| Total capacity | 78 GL (1.7×1010 imp gal; 2.1×1010 US gal) |
| Catchment area | 192.387 km2 (74.281 sq mi) + 287.688 km2 (111.077 sq mi) in Corin and Bendora Dam Catchments |
| Surface area | 285 ha (700 acres) |
| Website www.iconwater.com.au/cotterdam | |
The Cotter Dam is a concrete gravity and rockfill embankment dam across the Cotter River, located in the Australian Capital Territory, Australia. Both the dam and river are named after early settler in the area Garrett Cotter. The impounded Cotter Reservoir is a supply source of potable water for the city of Canberra and its environs.