The power plant portion of the dam is 332.5 m (1,091 ft) long and the tidal basin measures 22.5 km2 (9 sq mi).

An early attempt to build a tidal power plant was made at Aber Wrac'h in the Finistère in 1925, but due to insufficient finance, it was abandoned in 1930.

The idea of constructing a tidal power plant on the Rance dates to Gerard Boisnoer in 1921.

Charles de Gaulle, then President of France, inaugurated the plant on 26 November of the same year.

By definition, tides still flow in the estuary and the operator, EDF, endeavours to adjust their level to minimize the biological impact.

A lock for navigation at the west end of the dam allows the passage of 1,600-tonne vessels between the English Channel and the Rance.

The Rance estuary is the first part of the inland waterway from the English Channel to the Bay of Biscay via the Canal d'Ille-et-Rance and the river Vilaine.