Rio Grande dams and diversions are structures that store water along the Rio Grande or its tributaries, or that divert water for use in irrigation. The first diversions were made by the Pueblo Indians over 1,000 years ago.More permanent diversions were built by the Spanish in New Mexico to feed acequias, or shared irrigation canals.The first dam to impound the Rio Grande was the Rio Grande Dam, completed in 1914, followed by the Elephant Butte Dam, completed in 1916.