Étang de Soulcem, reservoir in France

Étang de Soulcem is a reservoir in the Vicdessos valley on the commune of Auzat, Haute-Ariège, held back at its northern end by a 275 m long earth-and-rockfill dam with a bituminous concrete upstream facing. The dam rises 66.50 m above the natural ground and 78 m above its foundations, and its crest sits at 1,581.50 m. The lake covers 0.90 km² and holds 29.30 hm³.

Électricité de France built the Pla de Soulcem dam between 1980 and 1983, flooding a plateau long used for pastoralism. Water drawn from the reservoir feeds the Soulcem power station near the hamlet of l'Artigue, commissioned in 1980, whose 409-metre drop produces 62 million kWh a year. The access road built for the dam also served a planned cross-border link with Andorra via the Port de Rat.

The name Soulcem comes from the plateau, the Pla de Soulcem, whose pastures were flooded when the reservoir filled. The dam road, built by Électricité de France, now carries the GRT62 long-distance footpath, which continues from the lake over the Spanish border at the Port de Bouet (2,509 m). Near the Labinas waterfall the GRT63 branches off toward Andorra and the Port de Rat (2,539 m).

The dam is reached from the village of Vicdessos by the D8 road, which follows the Mounicou stream south past the hamlet of Marc. The GRT62 long-distance trail takes the same route, then crosses into Spain at the 2,509 m Port de Bouet; the GRT63 branches off after the Labinas waterfall toward Andorra.

A notable feature is the large overflow spillway shaped like a tulip on the right bank that evacuates excess water during heavy rainfall. This safety structure demonstrates the engineering ingenuity used to manage massive water volumes and remains visible from across the lake.