Map Of The Rio Grande River Valley In New Mexico And Colorado Library Of Congress TexasNew Mexico Border to Presidio(Not mapped)258 miles The Rio Grande, from El Paso downstream to Presidio, is virtually a dry riverbed because of extensive irrigation in New Mexico However, the river becomes a permanent stream once again when the Rio Concho enters the streambed from Mexico, just upstream from PresidioOjinaga Rio Grande River The Rio Grande River is a principal river in North America that forms part of the United StatesMexico border and serves as the border between Texas and four Mexican states of Tamaulipas, Coahuila, Nuevo Leon, and Chihuahua In Mexico, the river goes by the name Rio Bravo del NorteThe Rio Grande is 3,051 kilometers long from its source at the Is the rio grande river dangerous