Draining of the Lake
Lac de Guerlédan
The Lac de Guerlédan is West of Mûr de Bretagne, and is Brittany’s largest lake.
Where to find the Lac de Guerlédan
The Lac de Guerlédan is South of the RN164 between Mûr de Bretagne and Gouarec.
The Lac de Guerlédan is visible from space
The lake’s main village is Beau Rivage on the North bank, with its restaurants, bars and hotel.
South of the lake is the forest of Quénécan, which covers about 11 square miles, within which lies the Anse de Sordan with its restaurant/bar.
In the heart of the forest are Les Forges des Salles, an important site for iron and steel making in the 18th and 19th centuries. Visitors can see the workers’ cottages, the manager’s house and the forges in this self-contained village that once had 150 inhabitants.
At the far west of the lake are the attractive remains of the 12th-century Cistercian Abbaye de Bon Repos (good rest).
At the Western end of the lake is the barrage/dam itself and below that the town of St. Aignan. Here you can find a mini model of the dam, built as a practice exercise, which is used to power St. Aignan. More information about the dams and the lake can be found at the Museum of Electricity, here.
The 7 miles (12km)-long Lac de Guerlédan was created in the 1920s at the same time as the dam which measures 147ft (45m) high by 675ft (206m) long, and which provides hydro-electricity for the surrounding region. The Barrage de Guerlédan took 7 years to build and was finally completed in 1930. The lake has been drained several times in the past - in 1951, 1966, 1975 and, most recently, 1985 - in order, then, as now, to maintain the dam in tiptop condition.
They will be starting to drain the lake for 6 weeks from April, 2015, and then, after about 6 months of work, they will spend another 6 weeks, around October/November, filling it up again.
Etymology of 'Guerlédan'
'Gwern', noun, a rivulet, marsh or site of a fountain. 'ledan', adjective, broad or large. So the area was apparently named for the river Blavet.