The Lac de Rillé was created in 1976/77 by constructing an earth dam on the River Lathan at Gué Morin near Breil in Maine et Loire. The lake stretches from Rillé in Indre et Loire to Breil and is bisected by a 'digue' forming two 'separate' lakes. The top part is known as the Lac de PIncemaille (literally 'pinched waist') and has a leisure beach, camping site and holiday cabins at what is known as 'Huttopia'; the lower part is preserved as a nature reserve (classified as one of Europe's key sites for wild life in the 'Natura 2000' series) and a special site for birds by the LPO, ('Ligue pour la Protection des Oiseaux). The main part of the lake is also a great attraction for fishermen and is well stocked with carp, 'silure' (huge catfish) and various other coarse fish. There are numerous species of birds, from herons to rare migratory birds, and ospreys have visited the lake in some summers.
The main purpose of the lake is for irrigation and when the lake is full at the end of winter, the River Lathan feeds irrigation schemes in the Loire Valley for horticulture and agriculture.