Llano Grande Lake

By: William MacWhorter

Type: General Entry

Published: March 1, 1995

Llano Grande Lake, two miles south of Weslaco in southeast Hidalgo County (at 26°07' N, 97°58' W), is part of the Rio Grande delta drainage system and lies within the Llano Grande Grant, which was conveyed by the Spanish government to Juan José Hinojosa, chief justice of Reynosa, Tamaulipas, in 1778. The lake, which is six miles long and 600 feet wide at its widest place, is supplied by Oso, Enguerrado, and Badena resacas, all of which enter from the west. Separate outflows from the eastern end of the lake form Arroyo Colorado and Lake Tampacuas, which flow into the Laguna Madre and the Gulf of Mexico.

The Salt Road from Rosario on the Rio Grande crossed Llano Grande Lake at El Salto, three miles north of the river, and continued northward another twenty-seven miles to lake Sal del Rey, the mineral rights of which were retained by the Spanish crown. The 1879 survey of the Llano Grande Grant shows ranchos Tenajo, Ranchito, and Ojo de Agua on the north bank of Llano Grande Lake. No trace of these ranches is found today.

Llano Grande Lake was formerly surrounded by thick vegetation. More than 200 species of trees, shrubs, cacti, vines, and grasses flourished there, watered by annual overflows of the Rio Grande. Only small areas of forest remained in 1991, as in the 1920s and 1930s vegetation was removed by landowners and by the International Boundary and Water Commission. Annual overflows are now prevented by upstream dams on the Rio Grande.

The Adams Unit of Las Palomas State Wildlife Refuge, the Mercedes Unit of Rio Grande Valley National Wildlife Refuge, and the Audubon Society's Los Rapidos Wildlife Sanctuary lie along the north shore of the lake. Each tract is richly forested in native trees and shrubs and inhabited by many species of reptiles, mammals, and birds, including the American alligator, ocelot, green jay, and chachalaca. Unusual plants include Sierra Madre torchwood, Texas sabal palm, Moctezuma cypress, brush holly, and devil's claw. Llano Grande Lake and its banks form a natural wildlife corridor connecting the Rio Grande with the Gulf of Mexico. In the context of rapid urbanization of the Rio Grande delta, the lake is very important to the survival of threatened wildlife species.

J. Lee and Lillian J. Stambaugh, The Lower Rio Grande Valley of Texas (San Antonio: Naylor, 1954).

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

William MacWhorter, “Llano Grande Lake,” Handbook of Texas Online, accessed June 26, 2022, https://www.tshaonline.org/handbook/entries/llano-grande-lake.

Published by the Texas State Historical Association.

March 1, 1995