Seth D. Breeding

DELTA LAKE. Delta Lake, in the Nueces-Rio Grande basin four miles north of Monte Alto and twenty-four miles northeast of McAllen in Hidalgo County (at 26°25' N, 97°56' W), was previously called Monte Alto Reservoir and has also been called Mesteñas Reservoir and Willacy Reservoir. It is an off-channel storage reservoir to the Rio Grande. The project, constructed in 1939, is owned and operated by the Hidalgo-Willacy Counties Water Control and Improvement District No. 1. It has a capacity of 25,000 acre-feet and a surface area of 2,371 acres at the elevation of 56½ feet above mean sea level and consists of two units. Water is diverted from the Rio Grande in Cameron County by a gravity canal system. From this main canal water is diverted to another canal, known as Mesteñas Canal, for distribution to land during the irrigation season or to a pumping plant that lifts surplus water to the reservoir for storage. When needed for irrigation, the water is released and flows back to the Mesteñas Canal for distribution. Until the late 1970s the lakes formed by the reservoir were used as recreational facilities by area residents. After the water was discovered to be contaminated by an excess of microorganisms, it was closed to swimmers, and the park no longer attracted visitors.

Image Use Disclaimer

All copyrighted materials included within the Handbook of Texas Online are in accordance with Title 17 U.S.C. Section 107 related to Copyright and “Fair Use” for Non-Profit educational institutions, which permits the Texas State Historical Association (TSHA), to utilize copyrighted materials to further scholarship, education, and inform the public. The TSHA makes every effort to conform to the principles of fair use and to comply with copyright law.

For more information go to:

If you wish to use copyrighted material from this site for purposes of your own that go beyond fair use, you must obtain permission from the copyright owner.


The following, adapted from the Chicago Manual of Style, 15th edition, is the preferred citation for this article.

Handbook of Texas Online, Seth D. Breeding, "DELTA LAKE," accessed July 19, 2019,

Uploaded on June 12, 2010. Published by the Texas State Historical Association.

Get this week's most popular Handbook of Texas articles delivered straight to your inbox