This segment of the river forms the southern boundary of Big Bend National Park. The principal land use in the segment, in addition to the protected areas, is rangeland with some irrigated farmland. A concern identified in the analyses is for phosphorus. The watershed in Texas that drains to this segment can be characterized as semi-arid and sparsely populated. The major land use in the watershed is rangeland, and most income is from sheep, goat, and cattle production.
Concerns identified are for chloride, sulfates and total dissolved solids.
No possible concerns are identified. Oil and natural gas are produced in the area. The cities of Laredo, Eagle Pass, and Del Rio are the major metropolitan areas and are also ports of entry to Mexico. Possible concerns are nitrogen and phosphorus. Due to elevated levels of fecal coliform bacteria, contact recreation use is not supported.