The Archipel project can be described as a vast program of development of the many water Systems in the Montréal region. Beginning with the search for a solution to the problem of frequent flooding around Montréal, Archipel has evolved into a many phased and integrated project, affecting one way or the other sixty-five municipalities. Its implementation would imply a precise control of the level and flows of the waters of the archipelago and a major series of controls over the Lachine rapids which could yield a few hundred megawatts of hydro-electric power.