The San Luis Valley is a region in south-central Colorado with a small portion overlapping into New Mexico. The valley is approximately 122 miles (196 km) long and 74 miles (119 km) wide, extending from the Continental Divide on the northwest rim into New Mexico on the south. It contains 6 counties and portions of 3 others. It is an extensive high-elevation depositional basin of approximately 8,000 square miles (21,000 km2) with an average elevation of 7,664 feet (2,336 m) above sea level. The valley is a section of the Rio Grande Rift and is drained to the south by the Rio Grande, which rises in the San Juan Mountains to the west of the valley and flows south into New Mexico. The San Luis Valley has a cold desert climate but has substantial water resources from the Rio Grande and groundwater.
The Rio Grande in the United States or the Río Bravo in Mexico, also known as P’osoge in Tewa and Tó Ba’áadi in Navajo, is one of the principal rivers in the southwestern United States and in northern Mexico. The length of the Rio Grande is 1,896 miles (3,051 km), making it the 4th longest river in the United States and in North America by main stem. It originates in south-central Colorado, in the United States, and flows to the Gulf of Mexico. The Rio Grande drainage basin (watershed) has an area of 182,200 square miles (472,000 km2); however, the endorheic basins that are adjacent to and within the greater drainage basin of the Rio Grande increase the total drainage-basin area to 336,000 square miles (870,000 km2).
Conejos County is a county located in the U.S. state of Colorado. As of the 2020 census, the population was 7,461. The county seat is the unincorporated community of Conejos.
Founded in 1851, the Town of Manassa is a Statutory Town and is the most populous municipality in Conejos County, Colorado, United States. The town's population was 947 at the 2020 United States Census.
The Gila River is a 649-mile-long (1,044 km) tributary of the Colorado River flowing through New Mexico and Arizona in the United States. The river drains an arid watershed of nearly 60,000 square miles (160,000 km2) that lies mostly within the U.S., but also extends into northern Sonora, Mexico.
The San Juan River is a major tributary of the Colorado River in the Southwestern United States, providing the chief drainage for the Four Corners region of Colorado, New Mexico, Utah, and Arizona. Originating as snowmelt in the San Juan Mountains of Colorado, it flows 383 miles (616 km) through the deserts of northern New Mexico and southeastern Utah to join the Colorado River at Glen Canyon.
The Conejos River is a tributary of the Rio Grande, approximately 92.5 miles (148.9 km) long, in south-central Colorado in the United States. It drains a scenic area of the eastern San Juan Mountains west of the San Luis Valley.
The Rio Chama, a major tributary river of the Rio Grande, is located in the U.S. states of Colorado and New Mexico. The river is about 130 miles (210 km) long altogether. From its source to El Vado Dam its length is about 50 miles (80 km), from El Vado Dam to Abiquiu Dam is about 51 miles (82 km), and from Abiquiu Dam to its confluence with the Rio Grande is about 34 miles (55 km).
Rio Grande National Forest is a 1.86 million-acre (7,530 km2) U.S. National Forest located in southwestern Colorado. The forest encompasses the San Luis Valley, which is the world's largest agricultural alpine valley, as well as one of the world's largest high deserts located around mountains. The Rio Grande rises in the forest, and the Continental Divide runs along most of its western border. The forest lies in parts of nine counties. In descending order of land area within the forest they are Saguache, Mineral, Conejos, Rio Grande, Hinsdale, San Juan, Alamosa, Archuleta, and Custer counties. Forest headquarters are currently located in Monte Vista, Colorado, but plan to move to Del Norte. There are local ranger district offices in Del Norte, La Jara, and Saguache.
La Manga Pass, elevation 10,230 ft (3,120 m), is a mountain pass in the San Juan Mountains of Colorado. The pass is situated in Rio Grande National Forest.
The Rio Puerco is a tributary of the Rio Grande in the U.S. state of New Mexico. From its source on the west side of the Nacimiento Mountains, it flows about 230 miles (370 km), generally south to join the Rio Grande about 20 miles (32 km) south of Belen and about 50 miles (80 km) south of Albuquerque. Its drainage basin is about 7,350 square miles (19,000 km2) large, of which probably about 1,130 square miles (2,900 km2) are noncontributing.
With a total area of 121,590 square miles (314,900 km2), New Mexico is the fifth-largest state, after Alaska, Texas, California, and Montana. Its eastern border lies along 103°W longitude with the state of Oklahoma, and 2.2 miles west of 103°W longitude with Texas. On the southern border, Texas makes up the eastern two-thirds, while the Mexican states of Chihuahua and Sonora make up the western third, with Chihuahua making up about 90% of that. The western border with Arizona runs along the 109° 03'W longitude. The southwestern corner of the state is known as the Bootheel. The 37°N parallel forms the northern boundary with Colorado. The states of New Mexico, Colorado, Arizona, and Utah come together at the Four Corners in New Mexico's northwestern corner. Its surface water area is about 292 square miles (760 km2).
The Jemez River is a tributary of the Rio Grande in eastern Sandoval County, New Mexico, United States.
Navajo River is a 54-mile-long (87 km) tributary of the San Juan River. It flows from a source in the South San Juan Wilderness of Conejos County, Colorado southwest past Chromo, Colorado. The river dips into New Mexico, passing just north of Dulce before heading northwest to a confluence with the San Juan in Archuleta County, Colorado. A large portion of its water is diverted across the Continental Divide to the Rio Grande basin as part of the San Juan–Chama Project.
Platoro Dam is a dam in Conejos County, Colorado.
Rio San Antonio is a tributary of the Conejos River in northern New Mexico and southern Colorado. Via the Conejos River, it is part of the upper Rio Grande system. The river is used extensively for irrigation in its lower course through the southern San Luis Valley.
The San Luis Hills are a group of small mountain ranges in Conejos and Costilla counties in the San Luis Valley in southern Colorado. The individual mountain ranges that make up the San Luis Hills include the Fairy Hills, the Brownie Hills, the Piñon Hills, and the South Piñon Hills. The San Luis Hills' highest point is Flat Top, elevation 9,206 feet
