Legislation creating the MRGCD was passed in 1925. The District was created to drain the waterlogged Middle Rio Grande Valley and reclaim the land for agriculture and development. Construction began in 1930. It took nearly five years to dig and link 1,200 miles of drains, ditches and acequias; build El Vado Dam and construct four diversion dams on the Rio Grande. Millions of cubic yards of dirt were moved in the process. At the time of its construction, the District was hailed as the savior of the Middle Rio Grande Valley.
Why had the Valley become waterlogged? Because the bed of the Rio Grand became higher than the surrounding land and leaked water into that land. Here are historic photos detailing the District's construction.