In the early 1900s, after the construction of the Elephant Butte storage dam, planning began for a project to divert water from the Rio Grande to irrigate crops for 50 miles through the Mesilla Valley. In late winter of 1908, the Leasburg Diversion Dam was completed. This concrete dam held back the flow of the Rio Grande not to create a storage reservoir, but to divert water into a canal, from which ditches delivered water to the communities of Dona Ana, Las Cruces, and Mesilla. The dam was constructed of reinforced concrete with some hand-placed rubble. Peñasco Rock on the eastern shore was used as the cast end for the dam, while the western end was concrete, and the openings for the canal headgates were cut into solid rock.