Rio Grande

Rio Grande, city (1991 pop. 172,422), Rio Grande do Sul state, S Brazil, on the Rio Grande River at the outlet of the Lagoa dos Patos (a tidal lagoon) to the Atlantic Ocean. It is an important outport for the city of Pôrto Alegre on the northern end of the lagoon. Rio Grande has oil refineries and factories producing foodstuffs, leather, and tires. The city was founded in 1737.

Rio Grande, name of several rivers of Brazil. The largest rises in S Minas Gerais state, SE Brazil, and flows c.650 mi (1,050 km) NW to the Paranaíba River, with which it forms the Paraná River. Its lower course forms part of São Paulo's northern boundary. The huge Furnas Dam with its reservoir near Passos, Minas Gerais, serves the industrial heart of Brazil with hydroelectricity.

Rio Grande, river, c.1,885 mi (3,000 km) long, rising in SW Colo. in the San Juan Mts. and flowing south through the middle of N.Mex., past Albuquerque, then coursing generally southeast as the border between Texas and Mexico, making a big bend (see Big Bend National Park), and eventually emptying into the Gulf of Mexico at Brownsville, Tex., and Matamoros, Mex. Other paired towns along the river are Laredo, Tex., and Nuevo Laredo, Mex. and El Paso, Tex., and Juárez, Mex. The river, known in Mexico as Río Bravo del Norte, is unnavigable except near its mouth, but is now often reduced to a trickle there by drought and the drawing off of water upstream.

The Rio Grande is an important source of internationally regulated irrigation, a use it has long been put to. Pueblos were thriving on its banks N of Las Cruces, N.Mex., and the Native Americans were practicing irrigation of the arid country, when Spanish explorer Francisco Vásquez de Coronado arrived (1540). Today, dams on the Rio Grande are used for irrigation, flood control, and regulation of the river flow. Elephant Butte Dam (completed 1916) and Caballo Dam (completed 1938) in New Mexico create reservoirs that serve large areas. Further downstream N of Del Rio, Tex., is the Amistad Dam (completed 1969); it is 6 mi (9.7 km) long and impounds a huge reservoir; Amistad National Recreation Area is there. Below Laredo are Falcon Dam (completed 1954) and its large reservoir. Near the mouth of the Rio Grande is the irrigation-dependent citrus-fruit and truck-farm region commonly called the Rio Grande Valley and developed principally in the 1920s. An agreement between the United States and Mexico in 1944 provided for future distribution of the river's water, but in drought years the amount reaching the United States is often less than what is called for under the treaty.

Shifts in the river's channel have led to border disputes between the United States and Mexico. Parts of its bed have been stabilized by canalization, and an international border commission mediates disputes. The 114-year controversy over the location of the border at El Paso was finally settled in 1968 when the water of the Rio Grande was diverted into a concrete channel. A 191-mi (307-km) section of the river on the American shore below Big Bend National Park is protected as the Rio Grande Wild and Scenic River (see National Parks and Monuments, table).

in Mexico Río Bravo

River, North America. One of the longest rivers of North America, it flows 1,900 mi (3,000 km) from its sources in the Rocky Mountains of southwestern Colorado, U.S., to the Gulf of Mexico. It rises high in the San Juan Mountains and flows generally south, passing southeast and forming the entire border between Texas and Mexico. The earliest European settlements were along the lower course of the river in the 16th century, but many of the Pueblo Indian settlements of New Mexico date from before the Spanish conquest. During the Spanish period, the middle and upper portions were called the Río del Norte, and the lower course was called the Río Bravo. It is a major source of irrigation. At the U.S.-Mexican border, it defines the edge of Big Bend National Park, Texas.

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Known as the Rio Grande in the United States and as the Río Bravo (or, more formally, the Río Bravo del Norte) in Mexico, this river, long, is the third longest river system in the United States and serves as a natural boundary along the border between the U.S. state of Texas and the Mexican states of Chihuahua, Coahuila, Nuevo León, and Tamaulipas.

Description

The Rio Grande rises in the east Rio Grande National Forest in the U.S. state of Colorado. It is formed by the confluence of several streams at the base of Canby Mountain, just east of the continental divide. From there, it flows through the San Luis Valley, then south into New Mexico through Albuquerque and Las Cruces to El Paso, Texas, where it begins to form the border between the U.S. and Mexico. A major tributary, the Río Conchos, enters at Ojinaga, Chihuahua, below El Paso, and supplies most of the water in the Texas border segment. Other known 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 oceangoing ships, nor are there smaller craft using it as a route. In fact it is barely navigable at all. Its natural flow is only 1/20 the volume of the Colorado River, and less than 1/100 that of the Mississippi.

The river has, since 1848, 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, it was across this river that Texan slaves fled when seeking their freedom, aided by Mexico's liberal colonization policies and abolitionist stance.

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

The US and Mexico share the waters of this river under a series of agreements administered by the joint US-Mexico Boundary and Water Commission. The most notable of these were signed in 1906 and 1944.

Use of that belonging to the US is regulated by the Rio Grande Compact, an interstate pact between Colorado, New Mexico and Texas. The Rio Grande is over-appropriated, that is, there are more users for the water than there is 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.

In the summer of 2001 a 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 subsequently dredged, but it re-formed almost immediately. Spring rains the following year flushed the re-formed sandbar out to sea, but it returned in the summer of 2002. As of September 2006, the river once again reaches the Gulf. However, ecologists fear that unless rainfall returns to normal levels during the next few years and strict water conservation measures are adopted by communities along the river, the Rio Grande may soon become extinct.

The Rio Grande rises in high mountains and flows for much of its length at high elevation; El Paso is 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 in its floodplain. From El Paso eastward the river flows through desert. Only in the sub-tropical lower Rio Grande Valley is there extensive irrigated agriculture. The river ends in a small sandy delta at the Gulf of Mexico. Due to the persistent period of dry weather, the river has only occasionally emptied into the Gulf Of Mexico since 2002. Google Satellite Map

Millions of years ago, the Rio Grande ended at the bottom of the Rio Grande Rift in Lake Cabeza de Vaca. But about one million years ago the stream was "captured" and began to flow east.

The Rio Grande was designated as one of the American Heritage Rivers in 1997.

Names and pronunciation

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 or . Because "río" means "river" in Spanish, the phrase "Rio Grande River" is redundant.

In Mexico it is known as Río Bravo or Río Bravo del Norte, "bravo" meaning "fierce" or "brave". There is a city along its banks that bears its name (Río Bravo, Tamaulipas) located 10 miles east of Reynosa, Tamaulipas, and directly across from the Texas city of Pharr.

Historically, the Rio Grande/Rio Bravo has been called:

• mets'ichi chena, Keresan, "big river"
• posoge, Tewa, "big river"
• paslápaane, Tiwa, "big river"
• hañapakwa, Towa, "great waters"
• tó ba-ade, Navajo, "female river" (the direction south is female in Navajo cosmology)

Rio del Norte was the most common name 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. Its use was first documented in 1582. The use of the modern English name Rio Grande began with the early American settlers in south Texas. By the late 19th century, the name Rio Grande for the entire river, from Colorado to the sea, had become standard in the United States.

Rio Bravo had become the standard Spanish name for the lower river, below its confluence with the Rio Conchos, by 1602.

Note that the four Pueblo names probably predate the Spanish entrada by several centuries.

Source for historical names:

Literature

• Paul Horgan, Great River: The Rio Grande in North American History. Volume 1, Indians and Spain. Vol. 2, Mexico and the United States. 2 Vols. in 1, 1038 pages - Wesleyan University Press 1991, 4th Reprint, ISBN 0-8195-6251-3

See also

• US-Mexico Border
• Rio Grande border disputes
• List of crossings of the Rio Grande
• List of Colorado rivers
• List of New Mexico rivers
• List of Texas rivers
• Rio Grande Wild and Scenic River
• Rio Grande Valley
• Rio Grande Gorge
• Rio Grande Trail

References

External links

• Border Stories: the only hand pulled ferry on the Rio Grande (video)
• 1854 map of Rio Grande entrance (hosted by the Portal to Texas History).
• Rio Grande Cam - in Mission Texas. Mexico is on the left and the US is on the right.
• Bibliography on Water Resources and International Law Peace Palace Library