Its construction created a prime fishing, boating and sailing destination, a national park with great walking trails and hunting areas, and a water reservoir that has been utilized for consumption and irrigation purposes, but most importantly, the construction of Amistad Dam created a manmade barrier to control the potentially deadly waters of the Rio Grande River. This week, Amistad Dam just turned 50 years old.
The dam is the largest of the storage dams and reservoirs built on the international reach of the Rio Grande River. It was dedicated on Sept. 8, 1969 by United States President Richard M. Nixon and Mexico President Gustavo Diaz Ordaz.
The primary purpose for which Amistad Dam was constructed is flood control and water storage for the benefit of the United States and Mexico, according to the International Boundary and Water Commission.
The dam is 6.1 miles long, stands 254 feet above the riverbed and consists of a concrete gravity spillway section within the river canyon flanked by earth embankments.
The dam has 16 spillway gates capable of releasing 1.5 million cubic feet per second. It is operated and maintained jointly by the United States and Mexico sections of the International Boundary and Water Commission.
The reservoir impounded by the dam extends up the Rio Grande River approximately 75 miles, has a surface area of 65,000 acres and a volume of 3.12 million acre feet at conservation elevation of 1117.00 feet above mean sea level.
The dam’s purpose is to mitigate the effects of flood and the loss of life and property below the dam; water conservation by making water available during times of drought, and power generation by driving hydroelectric power plants on both the U.S. and the Mexico sides.
The dam was conceived after the flood of 1954 caused by Hurricane Alice. The storm developed in the Gulf of Mexico, near Brownsville, made landfall within 24 hours of formation and went up the Rio Grande to stall over the Langtry and Del Rio area.
Rains near Langtry resulted in 27.10 in of rain at Pandale, causing the greatest rise on the Rio Grande since 1865, newspaper records show.
The river rose 30-60 feet at Eagle Pass and Laredo. An 86-foot wall of water rushed down the Pecos River washing out a bridge that normally sat 50 feet above the river. The international bridge at Laredo was also washed out.
The dam was constructed in accordance with the guidelines of the Water Treaty of 1944.
On July 7, 1960, U.S. Congress authorized funds for the project which was approved by President Dwight D. Eisenhower, and on Oct. 24 that same year Eisenhower and Mexican President Adolfo López Mateos met to celebrate the agreement.
The meeting began a long-standing tradition called Fiesta de Amistad, which is celebrated every year by representatives of both countries on or around Oct. 24.
Amistad Dam was built at the confluence of the Rio Grande and the Devils rivers, down the stream from the Pecos River. The dam serves as collection point for all three rivers’ flow.
The International Boundary and Water Commission will be holding a 50th anniversary celebration ceremony on the dam this Thursday, starting at 9 a.m.
The Amistad Dam Road at the United States Port of Entry near Del Rio will be closed all day Sept. 11-12 to prepare for the ceremony, the commission announced.
The ceremony is open to the public. The commission is advising those attending the ceremony to park at the Amistad Dam Field Office, 670 Texas Spur 349, and take the shuttle to the event at the center of the dam.