Rio Grande

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Rio Grande
Río Bravo del Norte, Tooh Baʼáadii(in Navajo), Kótsoi (in Jicarilla Apache)
Rio Grande in Big Bend NP.jpg
The Rio Grande at Big Bend National Park,
on the Mexico–U.S. border
Map of the Rio Grande drainage basin
Country United States, Mexico
State Colorado, New Mexico, Texas, Chihuahua, Coahuila, Nuevo León, Tamaulipas
Physical characteristics
SourceCanby Mountain, Continental Divide
  location San Juan Mountains, Rio Grande National Forest, [1] Colorado, United States
  coordinates 37°47′52″N107°32′18″W / 37.79778°N 107.53833°W / 37.79778; -107.53833 [2]
  elevation12,000 ft (3,700 m) [1]
Mouth Gulf of Mexico
Cameron County, Texas; Matamoros, Tamaulipas
25°57′22″N97°8′43″W / 25.95611°N 97.14528°W / 25.95611; -97.14528 Coordinates: 25°57′22″N97°8′43″W / 25.95611°N 97.14528°W / 25.95611; -97.14528 [2]
0 ft (0 m)
Length1,896 mi (3,051 km) [1]
Basin size182,200 sq mi (472,000 km2) [3]
  location Eagle Pass, Texas/Piedras Negras, Coahuila [4]
  average2,403 cu ft/s (68.0 m3/s) [4]
  minimum24 cu ft/s (0.68 m3/s)
  maximum964,000 cu ft/s (27,300 m3/s)
Basin features
  left Red River, Rio Hondo, Rio Pueblo de Taos, Embudo River, Santa Fe River, Galisteo Creek, Alamito Creek, Terlingua Creek, Pecos River, Devils River
  right Conejos River, Rio Chama, Jemez River, Rio Puerco, Rio Conchos, Rio Salado, Rio Alamo, San Juan River

The Rio Grande ( /ˈrˈɡrænd/ or /ˈrˈɡrɑːnd/ ; [5] [6] [7] Spanish : Río Bravo del Norte, Spanish pronunciation:  [ˈri.o ˈβɾaβo ðel ˈnoɾte] ( Loudspeaker.svg listen ) or simply Río Bravo) is one of the principal rivers (along with the Colorado River) in the southwest United States and northern Mexico. The Rio Grande begins in south-central Colorado in the United States and flows to the Gulf of Mexico. [8] After passing through the length of New Mexico along the way, it forms part of the Mexico–United States border. According to the International Boundary and Water Commission, its total length was 1,896 miles (3,051 km) in the late 1980s, though course shifts occasionally result in length changes. Depending on how it is measured, the Rio Grande is either the fourth- or fifth-longest river system in North America. [1]


The river serves as part of the natural border between the U.S. state of Texas and the Mexican states of Chihuahua, Coahuila, Nuevo León, and Tamaulipas. A very short stretch of the river serves as part of the boundary between the U.S. states of Texas and New Mexico. Since the mid–20th century, heavy water consumption by farms and cities along with many large diversion dams on the river has left only 20% of its natural discharge to flow to the Gulf. Near the river's mouth, the heavily irrigated lower Rio Grande Valley is an important agricultural region.

The Rio Grande's watershed covers 182,200 square miles (472,000 km2). [3] Many endorheic basins are situated within, or adjacent to, the Rio Grande's basin, and these are sometimes included in the river basin's total area, increasing its size to about 336,000 square miles (870,000 km2). [9]


Island within the Rio Grande from the North Valley in Albuquerque, New Mexico Rio Grande-2.jpg
Island within the Rio Grande from the North Valley in Albuquerque, New Mexico

The Rio Grande rises in the western part of the Rio Grande National Forest in the U.S. state of Colorado. The river is formed by the joining of several streams at the base of Canby Mountain in the San Juan Mountains, just east of the Continental Divide. From there, it flows through the San Luis Valley, then south into the Middle Rio Grande Valley in New Mexico, passing through the Rio Grande Gorge near Taos, then toward Española, and picking up additional water from the San Juan-Chama Diversion Project from the Rio Chama. It then continues on a southerly route through the desert cities of Albuquerque and Las Cruces to El Paso, Texas, and Ciudad Juárez, Chihuahua. In the Albuquerque area, the river flows past a number of historic Pueblo villages, including Sandia Pueblo and Isleta Pueblo. Below El Paso, it serves as part of the border between the United States and Mexico.

The official river border measurement ranges from 889 miles (1,431 km) to 1,248 miles (2,008 km), depending on how the river is measured. [1] A major tributary, the Rio Conchos, enters at Ojinaga, Chihuahua, below El Paso, and supplies most of the water in the border segment. Other tributaries include the Pecos and the smaller Devils, which join the Rio Grande on the site of Amistad Dam. Despite its name and length, the Rio Grande is not navigable by ocean-going ships, nor do smaller passenger boats or cargo barges use it as a route. It is barely navigable at all, except by small boats in a few places; at its deepest point, the river's depth is 60 feet (18 m). [10]

The Rio Grande rises in high mountains and flows for much of its length at high elevation; Albuquerque is 5,312 feet (1,619 m), and El Paso 3,762 feet (1,147 m) above sea level. In New Mexico, the river flows through the Rio Grande rift from one sediment-filled basin to another, cutting canyons between the basins and supporting a fragile bosque ecosystem on its flood plain. From El Paso eastward, the river flows through desert. Although irrigated agriculture exists throughout most of its stretch, it is particularly extensive in the subtropical Lower Rio Grande Valley. The river ends in a small, sandy delta at the Gulf of Mexico. During portions of 2001 and 2002, the mouth of the Rio Grande was blocked by a sandbar. In the fall of 2003, the sandbar was cleared by high river flows around 7,063 cubic feet per second (200 m3/s). [4]

Navigation was active during much of the 19th century, [11] with over 200 different steamboats operating between the river's mouth close to Brownsville and Rio Grande City, Texas. Many steamboats from the Ohio and Mississippi Rivers were requisitioned by the U.S. government and moved to the Rio Grande during the Mexican–American War in 1846. They provided transport for the U.S. Army, under General Zachary Taylor, to invade Monterrey, Nuevo León, via Camargo Municipality, Tamaulipas. Army engineers recommended that with small improvements, the river could easily be made navigable as far north as El Paso.[ citation needed ] Those recommendations were never acted upon.

The Brownsville & Matamoros International Bridge, a large swing bridge, dates back to 1910 and is still in use today by automobiles connecting Brownsville with Matamoros, Tamaulipas. The swing mechanism has not been used since the early 1900s, though, when the last of the big steamboats disappeared. At one point, the bridge also had rail traffic. Railroad trains no longer use this bridge. A new rail bridge (West Rail International Crossing) connecting the U.S. and Mexico was built about 15 miles west of the Brownsville & Matamoros International Bridge. It was inaugurated in August 2015. It moved all rail operations out of downtown Brownsville and Matamoros. [12] The West Rail International Crossing is the first new international rail crossing between the U.S. and Mexico in 105 years. [13] The Brownsville & Matamoros International Bridge is now operated by the Brownsville and Matamoros Bridge Company, a joint venture between the Mexican government and the Union Pacific Railroad.

At the mouth of the Rio Grande, on the Mexican side, was the large commercial port of Bagdad, Tamaulipas. During the American Civil War, this was the only legitimate port of the Confederacy. European warships anchored offshore to maintain the port's neutrality, and managed to do so successfully throughout that conflict, despite occasional stare-downs with blockading ships from the US Navy. It was a shallow-draft river port, with several smaller vessels that hauled cargo to and from the deeper-draft cargo ships anchored off shore. These deeper-draft ships could not cross the shallow sandbar at the mouth of the river. The port's commerce was European military supplies, in exchange for bales of cotton.


The Upper Rio Grande near Creede, Colorado Rio Grande Creede.jpg
The Upper Rio Grande near Creede, Colorado
Railway Bridges and the Great Customs Smelter (postcard, circa 1916) Railway Bridges and the Great customs smelter.jpg
Railway Bridges and the Great Customs Smelter (postcard, circa 1916)
US to Mexico over the Rio Grande Bridge of the Americas (El Paso-Ciudad Juarez), June 2016.jpg
US to Mexico over the Rio Grande

During the late 1830s and early 1840s, the river marked the disputed border between Mexico and the nascent Republic of Texas; Mexico marked the border at the Nueces River. The disagreement provided part of the rationale for the US invasion of Mexico in 1846, after Texas had been admitted as a new state. Since 1848, the Rio Grande has marked the boundary between Mexico and the United States from the twin cities of El Paso, Texas, and Ciudad Juárez, Chihuahua, to the Gulf of Mexico. As such, crossing the river was the escape route used by some Texan slaves to seek freedom. Mexico had liberal colonization policies and had abolished slavery in 1828. [14]

In 1899, after a gradual change to the river position, a channel was dug for flood control which moved the river, creating what was called Cordova Island, which became the center of the Chamizal dispute. Resolving the dispute took many years and almost resulted in a 1909 combined assassination attempt on the American and Mexican presidents.

In 1944, the US and Mexico signed a treaty regarding the river, [15] and in 1997, the US designated the Rio Grande as one of the American Heritage Rivers. Two portions of the Rio Grande are designated National Wild and Scenic Rivers System, one in northern New Mexico and the other in Texas, at Big Bend National Park.

In mid-2001, a 328-foot (100 m)-wide sandbar formed at the mouth of the river, marking the first time in recorded history that the Rio Grande failed to empty into the Gulf of Mexico. The sandbar was dredged, but reformed almost immediately. Spring rains the following year flushed the reformed sandbar out to sea, but it returned in mid-2002. By late 2003, the river once again reached the Gulf. [4]

River modifications

View of the Rio Grande from Overlook Park, White Rock, New Mexico Rio Grande White Rock Overlook Park View 2006 09 05.jpg
View of the Rio Grande from Overlook Park, White Rock, New Mexico

The United States and Mexico share the water of the river under a series of agreements administered by the International Boundary and Water Commission (IBWC), US-Mexico. The most notable of these treaties were signed in 1906 and 1944. [16] [17] The IBWC traces its institutional roots to 1889, when the International Boundary Committee was established to maintain the border. The IBWC today also allocates river waters between the two nations, and provides for flood control and water sanitation.

Use of that water belonging to the United States is regulated by the Rio Grande Compact, an interstate pact between Colorado, New Mexico, and Texas. The water of the Rio Grande is over-appropriated: that is, more users for the water exist than water in the river. Because of both drought and overuse, the section from El Paso downstream through Ojinaga was recently tagged "The Forgotten River" by those wishing to bring attention to the river's deteriorated condition. [18]

Rio Grande in west El Paso near the New Mexico state line Rio Grande EP Upper Valley.jpg
Rio Grande in west El Paso near the New Mexico state line

Dams on the Rio Grande include Rio Grande Dam, Cochiti Dam, Elephant Butte Dam, Caballo Dam, Amistad Dam, Falcon Dam, Anzalduas Dam, and Retamal Dam. In southern New Mexico and the upper portion of the Texas border segment, the river's discharge dwindles. Diversions, mainly for agricultural irrigation, have increased the natural decrease in flow such that by the time the river reaches Presidio, little or no water is left. Below Presidio, the Rio Conchos restores the flow of water. [1] Near Presidio, the river's discharge is frequently zero. Its average discharge is 178 cubic feet per second (5 m3/s), down from 945 cubic feet per second (27 m3/s) at Elephant Butte Dam. Supplemented by other tributaries, the Rio Grande's discharge increases to its maximum annual average of 3,504 cubic feet per second (99 m3/s) near Rio Grande City. Large diversions for irrigation below Rio Grande City reduce the river's average flow to 889 cubic feet per second (25 m3/s) at Brownsville and Matamoros. [4]


The major international border crossings along the river are at Ciudad Juárez and El Paso; Presidio and Ojinaga; Laredo and Nuevo Laredo; McAllen and Reynosa; and Brownsville and Matamoros. Other notable border towns are the Texas/Coahuila pairings of Del Rio Ciudad Acuña and Eagle Pass Piedras Negras.

Names and pronunciation

The Rio Grande (Rio del Norte) as mapped in 1718 by Guillaume de L'Isle Rio grande in 1718.jpg
The Rio Grande (Rio del Norte) as mapped in 1718 by Guillaume de L'Isle

Río Grande is Spanish for "Big River" and Río Grande del Norte means "Great River of the North". In English, Rio Grande is pronounced either /ˈrˈɡrænd/ or /ˈrˈɡrɑːnd/ .

In Mexico, it is known as Río Bravo or Río Bravo del Norte, bravo meaning (among other things) "furious" or "agitated".

Historically, the Pueblo and Navajo peoples also had names for the Rio Grande/Rio Bravo:

The four Pueblo names likely antedated the Spanish entrada by several centuries. [19]

Rio del Norte was most commonly used for the upper Rio Grande (roughly, within the present-day borders of New Mexico) from Spanish colonial times to the end of the Mexican period in the mid-19th century. This use was first documented by the Spanish in 1582. Early American settlers in South Texas began to use the modern 'English' name Rio Grande. By the late 19th century, in the United States, the name Rio Grande had become standard in being applied to the entire river, from Colorado to the sea. [19]

By 1602, Río Bravo had become the standard Spanish name for the lower river, below its confluence with the Rio Conchos. [19]


The largest tributary of the Rio Grande by discharge is the Rio Conchos, which contributes almost twice as much water as any other. In terms of drainage basin size, the Pecos River is the largest.

TributaryAverage dischargeDrainage basin
cu ft/s m3/s sq mikm2
San Juan River 36810 [4] 12,95033,500 [4]
Rio Alamo 1303.68 [4] 1,6754,340 [4]
Rio Salado 35410.0 [4] 23,32360,400 [4]
Rio San Rodrigo 1303.68 [4] 1,0502,720 [4]
Devils River 36210.3 [4] 137355 [21]
Pecos River 2657.50 [4] 44,402115,000 [22]
Rio Conchos 84824.0 [4] 26,40068,400 [23]
Rio Puerco 39.51.1 [24] 7,35019,000 [24]
Jemez River 59.51.68 [25] 1,0382,688 [25]
Santa Fe River 10.90.31 [26] 231598.3 [26]
Rio Chama 57116.2 [27] 3,1448,143 [27]
Conejos River 1764.98 [28] 8872,297 [28]

See also


  1. 1 2 3 4 5 6 Metz, Leon C. "Rio Grande". The Handbook of Texas Online. Retrieved July 17, 2010.
  2. 1 2 "Rio Grande". Geographic Names Information System . United States Geological Survey.
  3. 1 2 "Rio Grande NASQAN Program". United States Geological Survey. Archived from the original on July 4, 2011. Retrieved July 17, 2010.
  4. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 "Water Bulletin Number 75: Flow of the Rio Grande and Related Data; From Elephant Butte Dam, New Mexico to the Gulf of Mexico". International Boundary and Water Commission. 2005. Retrieved July 17, 2010.
  5. Oxford Pronunciation June 28, 2017
  6. Encyclopedia of Santa Fe June 28, 2017
  7. Washington State University June 28, 2017
  8. Mighty Rio Grande Now a Trickle Under Siege April 12, 2015
  9. Benke, Arthur C.; Colbert E. Cushing (2005). Rivers of North America. Academic Press. pp. 186–192. ISBN   978-0-12-088253-3.
  10. "Rio Grande River". Encyclopædia Britannica. Retrieved May 18, 2016. In some places the depth of the river has varied from nearly 60 feet (18 metres) to a bare trickle or nothing.
  11. Tom Lea (1957) The King Ranch writes that Richard King made his fortune as a riverman on the Rio Grande before he proposed marriage to Henrietta and started his cattle ranch.
  12. page 7
  14. "The UGRR on the Rio Grande"
  15. "Bibliography on Water Resources and International Law: Rio Grande". Peace Palace Library. Retrieved December 23, 2010.
  16. IBWC: Treaties Between the U.S. and Mexico Archived June 1, 2015, at the Wayback Machine
  17. Thompson, Olivia N., "Binational Water Management: Perspectives of Local Texas Officials in the U.S.-Mexico Border Region" (2009). Applied Research Projects. Texas State University. Paper 313.[ specify ]
  18. "Rio Grande Sucked Dry for Irrigation, Industry", CNN Saturday Morning News, (Aired June 9, 2001)
  19. 1 2 3 Source for historical names: Carroll L. Riley, 1995, Rio del Norte, University of Utah Press. ISBN   0-87480-496-5
  20. For the spelling of Navajo terms: Young, Robert W & William Morgan, Sr. The Navajo Language. A Grammar and Colloquial Dictionary. University of New Mexico Press. Albuquerque, NM: 1987.
  21. "Devils River Protection Campaign, Devils River Conservation Easements". The Nature Conservancy . Retrieved July 22, 2010.
  22. Largest Rivers of the United States, USGS
  23. "The Rio Conchos: An Essential Ribbon of Life". Environmental Defense Fund. Archived from the original on July 24, 2010. Retrieved July 20, 2010.
  24. 1 2 "Water resources data for the United States, Water Year 2009; gage 08353000 Rio Puerco near Barnardo, NM" (PDF). USGS . Retrieved July 21, 2010.
  25. 1 2 "Water resources data for the United States, Water Year 2009; gage 08329000, Jemez River below Jemez Canyon Dam, NM" (PDF). USGS . Retrieved July 20, 2010.
  26. 1 2 "Water resources data for the United States, Water Year 2009; gage 08317200 Santa Fe River above Cochiti Lake, NM" (PDF). USGS . Retrieved July 21, 2010.
  27. 1 2 "Water resources data for the United States, Water Year 2009; gage 08290000, Rio Chama near Chamita, NM" (PDF). USGS . Retrieved July 21, 2010.
  28. 1 2 "Water resources data for the United States, Water Year 2009; gage 08249000, Conejos River near Lasauses, CO" (PDF). USGS . Retrieved July 21, 2010.

Further reading

Primary sources

Related Research Articles

Matamoros, Tamaulipas City in Tamaulipas, Mexico

Matamoros, officially known as Heroica Matamoros, is a city in the northeastern Mexican state of Tamaulipas. It is located on the southern bank of the Rio Grande, directly across the border from Brownsville, Texas, in the United States. Matamoros is the second largest city in the state of Tamaulipas. As of 2016, Matamoros had a population of 520,367. In addition, the Matamoros–Brownsville Metropolitan Area has a population of 1,387,985, making it the 4th largest metropolitan area on the Mexico–US border. Matamoros is the 39th largest city in Mexico and anchors the second largest metropolitan area in Tamaulipas.

Chamizal dispute

The Chamizal dispute was a border conflict over about 600 acres (2.4 km2) on the Mexico–United States border between El Paso, Texas, and Ciudad Juárez, Chihuahua. It was caused by a shift in the Rio Grande, as a survey presented in 1852 marked differences between the bed of the Rio Grande and the present channel of the river. Tensions over the territory during the historic Taft–Diaz summit almost resulted in the attempted assassination of both presidents on October 16, 1909.

Gateway Bridge may refer to:

The International Boundary and Water Commission is an international body created by the United States and Mexico in 1889 to apply the rules for determining the location of their international boundary when meandering rivers transferred tracts of land from one bank to the other, as established under the Convention of November 12, 1884.

The Rio Grande has changed course several times in recorded history, leading to a number of border disputes and uncertainties, both international and between individual U.S. states:

The Boundary Treaty of 1970 is a treaty between the United States and Mexico that settled all outstanding boundary disputes and uncertainties related to the Rio Grande border between them.

Rio Conchos river in Mexico

The Río Conchos is a large river in the Mexican state of Chihuahua. It joins the Río Bravo del Norte at the town of Ojinaga, Chihuahua.

Amistad Reservoir reservoir on the Rio Grande at its confluence with the Devils River in Texas and Mexico

Amistad Reservoir is a reservoir on the Rio Grande at its confluence with the Devils River 12 miles (19 km) northwest of Del Rio, Texas. The lake is bounded by Val Verde County on the United States side of the international border and by the state of Coahuila on the Mexican side of the border; the American shoreline forms the Amistad National Recreation Area. The reservoir was formed in 1969 by the construction of Amistad Dam. The dam and lake are managed jointly by the governments of the United States and Mexico through the International Boundary and Water Commission. The name of the dam and lake is the Spanish word for "friendship". The reservoir is also known as Lake Amistad.

Bagdad, Tamaulipas human settlement in Mexico

Bagdad, Tamaulipas, Mexico was a town established in 1848 on the south bank of the mouth of the Río Grande. This town is also known as the Port of Bagdad or the Port of Matamoros, since it is inside the municipality of Matamoros, Tamaulipas. Officially declared non-existent in 1880, it is now invisible, covered by the shifting sands of time.

Río Bravo, formally Ciudad Río Bravo, is a city on the northern border of the state of Tamaulipas in northeastern Mexico.

Bridge of the Americas (El Paso–Ciudad Juárez)

The Bridge of the Americas (BOTA) is a group of international bridges which cross the Rio Grande and Texas State Highway Loop 375, connecting the Mexico–United States border cities of Ciudad Juárez, Chihuahua and El Paso, Texas, via the MX 45 from the south and the I-110 from the north, crossing the El Paso BOTA Port of Entry. The bridge is colloquially known as "Puente Libre" in Ciudad Juárez, officially as "Puente Internacional Córdova-Las Américas" or "Puente Internacional Córdova de las Américas", and also known as "Puente Río Bravo", "Cordova Bridge" and "Free Bridge".

Stanton Street Bridge international bridge between El Paso, Texas, United States and Ciudad Juárez, Chihuahua, Mexico

The Good Neighbor International Bridge, commonly known as the Stanton Street Bridge, is an international bridge connecting the United States-Mexico border cities of El Paso, Texas, and Ciudad Juárez, Chihuahua across the Rio Grande. The bridge is also known as "Friendship Bridge", "Puente Río Bravo" and "Puente Ciudad Juárez-Stanton El Paso". The Good Neighbor International Bridge is a five lane bridge with 3 lanes for south bound traffic and one for Secure Electronic Network for Travelers Rapid Inspection northbound traffic. The bridge was completed in 1967 and is 880 feet (270 m) long. The U.S. side of the bridge is owned and operated by the City of El Paso.

Paso del Norte International Bridge

The Paso del Norte International Bridge is an international bridge which crosses the Rio Grande connecting the United States-Mexico border cities of El Paso, Texas, and Ciudad Juárez, Chihuahua. The bridge is also known as "Paso del Norte Bridge", "Santa Fe Street Bridge", "Puente Benito Juárez", "Puente Paso del Norte" and "Puente Juárez-Santa Fe". The Paso del Norte International Bridge is a four-lane bridge for northbound non-commercial traffic only. The bridge was constructed in 1967. The American side of the bridge is owned and operated by the City of El Paso.

Rio Grande Project

The Rio Grande Project is a United States Bureau of Reclamation irrigation, hydroelectricity, flood control, and interbasin water transfer project serving the upper Rio Grande basin in the southwestern United States. The project irrigates 193,000 acres (780 km2) along the river in the states of New Mexico and Texas. Approximately 60 percent of this land is in New Mexico. Some water is also allotted to Mexico to irrigate some 25,000 acres (100 km2) on the south side of the river. The project was authorized in 1905, but its final features were not implemented until the early 1950s.

El Paso–Juárez Metropolitan Area

El Paso–Juárez, also known as Juárez–El Paso, the Borderplex or Paso del Norte, is a binational metropolitan area, or conurbation, on the border between Mexico and the United States. The region is centered on two large cities: Ciudad Juárez, Chihuahua, Mexico and El Paso, Texas, U.S. Additionally, nearby Las Cruces, New Mexico, U.S. is sometimes included as part of the region, referred to as El Paso–Juárez–Las Cruces or El Paso–Juárez–Southern New Mexico. With over 2.7 million people, this binational region is the 2nd largest metropolitan area on the United States–Mexico border. The El Paso–Juárez region is the largest bilingual, binational work force in the Western Hemisphere.

Amistad Dam dam in Val Verde County, Texas / Acuña Municipality, Coahuila

Amistad Dam is a major embankment dam across the Rio Grande between Texas, United States, and Coahuila, Mexico. Built to provide irrigation water storage, flood control, and hydropower generation, it is the largest dam along the international boundary reach of the Rio Grande. The dam is over 6 miles (9.7 km) long, lies mostly on the Mexican side of the border, and forms Amistad Reservoir. It supplies water for irrigation in the Rio Grande Valley, 574 miles (924 km) upstream of the Rio Grande's mouth on the Gulf of Mexico at Brownsville, Texas/Matamoros, Tamaulipas.

Matamoros–Brownsville metropolitan area Metropolitan area

Matamoros–Brownsville, also known as Brownsville–Matamoros, or simply as the Borderplex, is one of the six bi-national metropolitan areas along the Mexico–United States border. The city of Matamoros is situated in the Mexican state of Tamaulipas, on the southern bank of the Rio Grande, while the city of Brownsville is located in the U.S. state of Texas, directly north across the bank of the Rio Grande. The Matamoros–Brownsville is connected by four international bridges. In addition, this transnational conurbation area has a population of 1,136,995, making it the 4th largest metropolitan area in the Mexico-U.S. border.

American Diversion Dam dam in El Paso, Texas / Sunland Park, New Mexico

The American Diversion Dam is a diversion dam on the Rio Grande in El Paso, Texas. It is about 140 feet (43 m) north of the point where the west bank of the river enters Mexico, 3.5 miles (5.6 km) from the business center. The dam is operated by the International Boundary and Water Commission. It started operation in 1938.

International Diversion Dam dam in Ciudad Juárez, Chihuahua, Mexico

The International Diversion Dam is a diversion dam on the Rio Grande in Ciudad Juárez. The dam is operated by the International Boundary and Water Commission, and diverts water into the Acequia Madre for use in irrigation in Mexico. Water is diverted under the terms of the 1906 treaty on usage of Rio Grande water between the United States and Mexico.

Riverside Diversion Dam dam in El Paso, Texas

The Riverside Diversion Dam was a diversion dam on the Rio Grande to the southeast of El Paso, Texas. The dam was owned by the United States Bureau of Reclamation, and diverted water into the Riverside Canal for use in irrigation in the El Paso Valley. The dam became obsolete with completion of a cement-lined canal carrying water from the upstream American Diversion Dam to the head of the canal. It was partially removed in 2003.