Lake San Mauricio is an enlarged Pyrenean lake with a small dam located in the municipality of Espot, in the Aiguas Tortas and San Mauricio Lake National Park.

It is located at an altitude of 1910 meters, at the bottom of a glacial cirque.

It receives the waters of the Ratera, Portarró and Subenuix rivers and streams, while its emissary, the Escrita river, drains the Espot valley to the Noguera Pallaresa.

The lake is about 1,100 m long by about 200 wide, with a water volume of 2.6 hm ³, thanks to a dam built to increase its capacity.

Surrounded by black pine forests and a beautiful mountain landscape, is the hermitage of San Mauricio, an (abandoned) military refuge and a hydroelectric dam that follows the shore.

There is a 6 km long channel that brings water to a regulating reservoir; from there a 1 km long pipeline leads to the San Mauricio plant (together with the water from the Lladres plant), located near Spot de Dalt, on the right bank of the Escrita river.

The jump from the lake is 579 meters, the installed power of 15,543 kW and the production of 35.9 to 54 MWh.