The Rio Grande rises from south-central Colorado and flows to the Gulf of Mexico, acting in part as the border between Mexico and the United States. Its length is 1,896 miles – 3,051 km – and is the fourth longest river system in North America. Since the mid–20th century, heavy water consumption of farms and cities as well as several large dams has left only 20 percent of its natural discharge to flow to the Gulf. Also, the heavily irrigated lower Rio Grande Valley near the river’s mouth is an important agricultural region. The watershed covers 182,200 square miles – 472,000 km2.
Geography the Rio Grande begins it journey in the western part of Colorado’s Rio Grande National Forest and it is formed by several streams at the base of Canby Mountain. From there, it flows through the San Luis Valley and Albuquerque, New Mexico. Below El Paso, Texas it serves as part of the border between the United States and Mexico.
The Rio Grande Flows for much of its Length at High Elevation
Navigation was active during much of the 19th century with over 200 steamboats operating between Brownsville and Rio Grande City, Texas. Currently, it is navigable only with small boats; its average depth is ten feet.