The United States Section of the International Boundary & Water Commission (USIBWC) operates and maintains three flood control systems on the Rio Grande. Currently, the USIBWC is in the process of rehabilitating and/or improving deficient segments in its three Rio Grande Flood Control Systems. These flood control systems are: the Upper Rio Grande Flood Control System, Presidio Valley Flood Control System, and the Lower Rio Grande Flood Control System.
The Upper Rio Grande Flood Control System consists of 223 miles of flood control levee alongside 197 miles of the Rio Grande from Caballo, New Mexico to Little Box Canyon, Texas; located about 10 miles downstream of Fort Quitman, Texas. The Rio Grande runs 106 miles from Caballo to the downstream end of American Dam in El Paso, Texas, where it becomes the international boundary about 16 miles south from the New Mexico – Texas state line. This 106-mile stretch of the Rio Grande is referred to the old Canalization Project segment and is bounded by 130 miles of levees; 57 miles on its west side and 73 miles on its east. The Upper Rio Grande Flood Control System continues downstream for another 91 miles from El Paso to Little Box Canyon. This stretch of the Rio Grande is referred to as the old Rectification Project segment and is confined by approximately 93 miles of river and spur levees on the U.S. floodplain. The Upper Rio Grande Flood Control System protects approximately 1 million U.S. residents in the following metropolitan statistical areas: Las Cruces, New Mexico and El Paso, Texas.
The Presidio Valley Flood Control System is located upstream of Big Bend National Park in Texas. This flood control system consists of 15 miles of levee on U.S. floodplain that parallels the Rio Grande. The Rio Conchos, the main Mexican tributary from the state of Chihuahua, enters the Rio Grande at Presidio, where it increases normal flow by 10 to 20 times. The design flood for the Rio Grande is 3600 cfs above the confluence with the Rio Conchos and 42,000 cfs below. The Presidio Valley Flood Control System provides flood protection to roughly 52 square miles of urban and agricultural land in Presidio; a Texas town of nearly 5000 residents.
The Lower Rio Grande Flood Control System contains 270 miles of U.S. flood control levee along the Rio Grande, interior floodways, and the Arroyo Colorado in Texas. Flood control works along the Rio Grande include 102 miles of levees and floodplain from Peñitas, Texas to beyond Brownsville, Texas. The interior floodway, which starts 13 levee-miles downstream from Peñitas at Anzalduas Dam, is about 70 miles long and is bounded by 143 miles of levees; 68 miles on the right side and 75 miles on the left side. The Arroyo Colorado, a 53-mile natural channel that breaks-off the interior floodway, is confined by high ground and 25 miles of levee; 10.5 miles on the left side and 14.6 miles on the right side. The Lower Rio Grande Flood Control System provides protection to the following metropolitan statistical areas: Brownsville-Harlingen, Texas and McAllen-Edinburg-Mission, Texas. Approximately one million U.S. residents live in the Lower Rio Grande Valley. Due to its proximity to the Gulf of Mexico and related tropical weather systems, the Lower Rio Grande Valley is prone to hurricanes and annual flood events.
The ARRA provided the necessary resources to address a significant portion of high-priority levee segments within the Upper Rio Grande, Presidio Valley, and Lower Rio Grande Flood Control Systems in need of rehabilitation or improvement. As a result, the IBWC issued 16 contracts for construction of approximately 236.5 miles of infrastructure improvements to include levees, floodwalls, floodgates, and ancillary structures at crossings. A master schedule, providing the estimated timelines of the ARRA infrastructure improvements, may be accessed at the following link: ARRA Progress Schedule