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Lower Rio Grande Flood Control System

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.

LRGFCP Brochure

Hydraulic Model of the Rio Grande and Floodways within the LRGFCP