| Étang de Soulcem | |
| Dam Crosses: | Rousseau de Mounicou |
| Res Name: | Étang de Soulcem |
| Location: | Vicdessos valley, Ariège, France |
| Operator: | Électricité de France |
| Dam Length: | 275m (902feet) |
| Dam Height: | 66.5m (218.2feet) |
| Plant Hydraulic Head: | 409m (1,342feet) (via chutes to the Soulcem hydro plant) |
| Dam Width Base: | 15m (49feet) |
| Construction Began: | 1980 |
| Opening: | 1983 |
| Res Capacity Total: | 29300000m2 |
| Res Catchment: | 44.3km2 |
| Res Surface: | 0.91km2 |
| Plant Annual Gen: | 62 GWh/year |
| Coordinates: | 42.6681°N 1.4467°W |
| Extra: | Average flow 7 m3/s Peak flow 85 m3/s Evacuation flow134 m3/s |
Étang de Soulcem is a large artificial lake in the Pyrenees mountains in Ariège, France. It is at an elevation of 1570 m and is used for hydroelectricity, generating 62 GWh/year. The lake, which has a surface area of 0.91 km2, was formed following the construction by Électricité de France of a dam across the northern end of the Vicdessos valley in 1980–1983.
The lake contains various fish including brown trout (S. trutta), Arctic char (S. alpinus), brook trout (S. fontinalis), and common minnow (P. phoxinus).