Rio Grande


New Mexico became the 47th U.S. state in 1912.  It is located at a longitude of 103°W to 109°W and a latitude of 31° 20’N to 37°N. 

Geographically it is the fifth largest state yet it has the least amount of surface water of all 50 states, as a percentage of its land mass (0.2%).  If you want to know how “wet” your state is, click here

The two largest rivers are the Rio Grande and Pecos.  The Pecos is actually a tributary of the Rio Grande.

The state’s population is approximately 2 million people, with about 900,000 people living in the Albuquerque metropolitan area.

RiverXchange classes in New Mexico currently come from Albuquerque, Rio Rancho and outlying areas of Bernalillo and Sandoval Counties.  Albuquerque is in the center of the state.  Rio Rancho is adjacent to/northwest of Albuquerque.   Santa Fe (the state capital) is about 65 miles north of both cities.  These communities are located at altitudes of 5000-7500′ above sea level.

The Rocky Mountains begin in British Columbia (Canada) and end in New Mexico.  The 50 highest peaks in New Mexico are all over 11,000 feet in elevation, with Wheeler Peak (near Taos, in northern NM) being the highest peak at 13,161 feet.

The Continental Divide runs through the entire length of New Mexico, closely following the path of the Rio Grande.  The Divide represents a major U.S. division of watersheds: all precipitation that falls to the west of the Divide eventually makes its way to the Pacific Ocean, while precipitation that falls to the east of the Divide makes its way to the Atlantic Ocean.

The diverse geology of the state provides terrain that includes six of the seven “life zones.”  A life zone is a belt of vegetation and animal life that appears with increases in altitude and increases in latitude.  With such a variation in landscapes, the animal and plant species also represent a vast range like no other on the planet.  To learn more about life zones in New Mexico, click here.  

The Rio Grande did not carve its own valley; rather, the valley appeared first and the river followed.  This “rift valley” was created when the earth’s crust separated due to faulting and other earth movements caused by the North American and Pacific plates scraping against each other millions of years ago.


The high desert climate is classified as arid to semi-arid, with lots of sunshine and very low humidity.  Average precipitation in Albuquerque is about 9″ per year, and the state average is about 14″.  Albuquerque receives 9-10″ of snow annually, while higher elevations/northern mountains get up to 100″ annually.  Most precipitation falls as rain during the summer months.

Much of New Mexico is located in the Upper Chihuahuan Desert, which is colder than the Sonoran desert in Arizona.  The saguaro cactus — a symbol of the wild west — is rarely found in New Mexico due to prolonged freezing temperatures.  Well-known native plants include yucca, cholla cactus, prickly pear cactus, piñon pine, juniper, cottonwood (in riparian areas), and Ponderosa pine (in higher elevations).  Click here to learn more about New Mexico’s native plants.

Many people would be surprised to learn that the number of days above 90 degrees and below 32 degrees in Albuquerque is about the same as in the Washington, D.C. area!

Rio Grande

Río Grande is Spanish for “Big River.” (Río means “river” in Spanish, so there is no need to say Rio Grande River.)  Nearly all New Mexico mountain ranges, rivers, streams and towns have Spanish language or native language names, reflecting the influence of two very different cultures that have had a major impact on the history and development of the state.  Examples of water/geology-related Spanish language words that have been adopted into contemporary New Mexican culture include playa (dry lake), arroyo (dry river, creek or stream bed), mesa (elevated area of land with a flat top (table) and sides), bosque (riparian forest), acequia (community-based irrigation; also referred to as ditch irrigation) and mayordomo (ditch boss).  New Mexico’s community acequias are the oldest water management institutions in the U.S. of European origin.  To learn more about New Mexico’s acequia culture, click here.

The Rio Grande’s length is approximately 1,885 miles, starting in southern Colorado and ending in a sandy delta at the Gulf of Mexico.  It is the fourth longest river system in North America and forms the border between the U.S. and Mexico.  It is called the Río Bravo del Norte or Río Bravo in Mexico.  Principal tributaries are the Pecos, Devils, Conejos, Chama and Puerco rivers in the United States, and the Conchos, Salado and San Juan in Mexico.  In the Middle Rio Grande (home to Rio Rancho and Albuquerque), the largest tributary to the Rio Grande is Albuquerque’s Southside Water Reclamation Plant!

Today, there are sections of the river that run dry, and the Rio Grande does not always reach the Gulf of Mexico.  This is due to intense human development and agricultural water use upstream in Colorado, New Mexico and Texas.

Statewide, municipalities get about 90% of their drinking water from the ground (aquifer).  The Rio Grande provides about 56% of the water needed agriculture in the Rio Grande Basin.  The remaining water comes from the ground.  For more information about New Mexico’s water use, click here.

Fecal coliform/e.coli (from human and animal waste), endangered species, overpumping of groundwater, and increased demands on the Rio Grande for municipal drinking water are growing threats.  From a hydrological point of view, surface water and groundwater are almost always connected.  This is why overpumping of one eventually affects the other, and why pollution of one eventually affects the other.  To learn more about the surface water-groundwater connection, click here.

The Rio Grande and its unique riparian area provide critical habitat for many animals including migrating birds between Mexico and Canada.  In the Middle Rio Grande, the two endangered species of particular concern are the Southwestern willow flycatcher and the Rio Grande silvery minnow.  To learn about all of New Mexico’s endangered species, click here.

Return to the top of this page