 Moreover, the responsibility of water supply and sanitation was specifically designated to the federal government, a duty that was maintained for many decades post-revolution.In the second half of the 20th century, the Mexican water supply and sanitation sector has undergone several changes of organization to improve its performance.Since 1948, during the presidency of Miguel Alemán (1946-1952), responsibility for Mexican urban water supply systems was vested in the Ministry of Water Resources ("Secretaría de Recursos Hídricos" – SRH) under the federal government.