Lac d'Izourt, French lake

Lac d'Izourt is an artificial reservoir in the high Vicdessos valley, on the commune of Auzat in Ariège. Its dam is a gravity structure of masonry and cyclopean concrete on a granite base, 42 m high with a 162 m crest and a 30 m base. The lake lies at 1,652 m on the Artiès stream.

The valley once held natural lakes formed after the last Ice Age, but a dam was built from 1937 to 1940 to store water for hydroelectric power plants. On March 24, 1939, a catastrophic windstorm struck the construction site, killing 31 workers and leaving deep scars in local memory.

The lake is reachable by foot from the village of Auzat after a walk of several kilometers, with the path passing through forest and open terrain. The route is relatively flat with gentle climbs and can be managed with basic footwear, allowing roughly three to four hours for a round trip.

The dam is a gravity structure of masonry and cyclopean concrete on a granite base, 42 m high with a 162 m crest. Italian workers from the Alps, housed in stone barracks on the right bank just downstream, left traces still visible today. The 1939 storm was long officially called an avalanche; recent memory work established that the barracks collapsed under the weight of exceptional snow.