The body of water is located in the municipality of Vagli Sotto in the province of Lucca and was formed artificially with the damming of the Edron stream in 1947 by SELT Valdarno (now Enel s.p.a.) and the construction of a hydroelectric dam designed by Count Eng. Ignazio Prinetti Castelletti as recalled by an inscription fixed to the wall between the steps on the western bank. In 1948 the works on the dam were completed with the subsequent raising to 92 meters. The rising waters of the lake submerged some villages among which the main one was Fabbriche di Careggine, a small village of blacksmiths from Brescia, founded in the 13th century, which re-emerges every time the lake is emptied. The lake contains approximately 35 million cubic meters of water and is emptied exceptionally if maintenance is necessary. It has happened four times: in 1958, 1974, 1983 and 1994. The new emptying was expected for 2024, but due to the water needs caused by recent droughts, it was decided to postpone the emptying to 2026 (unless it becomes necessary to postpone it again). The wait for the new emptying is linked to the tourist attraction offered by the re-emergence of the village of Fabbriche di Careggine, whose structure (including the beautiful church of San Teodoro) is still substantially intact under the waters of the lake.