The Gila River (;
O'odham ">ima Keli Akimel or simply Akimel,
Quechan
The Quechan (or Yuma) ( Quechan: ''Kwatsáan'' 'those who descended') are a Native American tribe who live on the Fort Yuma Indian Reservation on the lower Colorado River in Arizona and California just north of the Mexican border. Despite th ...
: Haa Siʼil,
Maricopa language
Maricopa or Piipaash is spoken by the Native American Maricopa people on two reservations in Arizona: the Salt River Pima-Maricopa Indian Community and the Gila River Indian Community. Most speakers live in Maricopa Colony. The language is con ...
: Xiil) is a
tributary
A tributary, or affluent, is a stream or river that flows into a larger stream or main stem (or parent) river or a lake. A tributary does not flow directly into a sea or ocean. Tributaries and the main stem river drain the surrounding drainage ...
of the
Colorado River
The Colorado River ( es, Río Colorado) is one of the principal rivers (along with the Rio Grande) in the Southwestern United States and northern Mexico. The river drains an expansive, arid drainage basin, watershed that encompasses parts of ...
flowing through
New Mexico
)
, population_demonym = New Mexican ( es, Neomexicano, Neomejicano, Nuevo Mexicano)
, seat = Santa Fe
, LargestCity = Albuquerque
, LargestMetro = Tiguex
, OfficialLang = None
, Languages = English, Spanish ( New Mexican), Navajo, Ker ...
and
Arizona
Arizona ( ; nv, Hoozdo Hahoodzo ; ood, Alĭ ṣonak ) is a state in the Southwestern United States. It is the 6th largest and the 14th most populous of the 50 states. Its capital and largest city is Phoenix. Arizona is part of the Fou ...
in the United States. The river drains an arid watershed of nearly that lies mainly within the U.S., but also extends into northern
Sonora
Sonora (), officially Estado Libre y Soberano de Sonora ( en, Free and Sovereign State of Sonora), is one of the 31 states which, along with Mexico City, comprise the Administrative divisions of Mexico, Federal Entities of Mexico. The state is d ...
,
Mexico
Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...
.
Indigenous peoples have lived along the river for at least 2,000 years, establishing complex agricultural societies before European exploration of the region began in the 16th century. However,
European Americans
European Americans (also referred to as Euro-Americans) are Americans of European ancestry. This term includes people who are descended from the first European settlers in the United States as well as people who are descended from more recent E ...
did not permanently settle the Gila River watershed until the mid-19th century.
During the 20th century, human development of the Gila River watershed prompted the construction of large diversion and flood control structures on the river and its tributaries, and consequently the Gila now contributes only a small fraction of its historic flow to the Colorado. The historic natural discharge of the river is around , and is now only . These engineering projects have transformed much of the river valley and its surrounds from arid desert to irrigated land, and supply water to the more than five million people, mainly in the Phoenix and Tucson metropolitan areas, who live in the watershed .
Geography
The Gila River has its source in western New Mexico, in
Sierra County on the western slopes of the
Continental Divide
A continental divide is a drainage divide on a continent such that the drainage basin on one side of the divide feeds into one ocean or sea, and the basin on the other side either feeds into a different ocean or sea, or else is endorheic, not ...
in the
Black Range. It flows southwest through the
Gila National Forest
The Gila National Forest is a protected national forest in New Mexico in the southwestern part of the United States established in 1905. It covers approximately of public land, making it the sixth largest National Forest in the continental U ...
and the
Gila Cliff Dwellings National Monument
Gila Cliff Dwellings National Monument is a U.S. National Monument created to protect Mogollon cliff dwellings in the Gila Wilderness on the headwaters of the Gila River in southwest New Mexico. The national monument was established by President ...
, then westward into Arizona, past the town of
Safford. After flowing along the southern slope of the
Gila Mountains in
Graham County through a series of canyons, the Gila is impounded by
Coolidge Dam
The Coolidge Dam is a reinforced concrete multiple dome and buttress dam southeast of Globe, Arizona on the Gila River. Built between 1924 and 1928, the Coolidge Dam was part of the San Carlos Irrigation Project. Coolidge Dam was named after ...
in
San Carlos Lake
San Carlos Lake was formed by the construction of the Coolidge Dam and is rimmed by of shoreline. The lake is located within the San Carlos Apache Indian Reservation, and is thus subject to tribal regulations.
After it was built, the reservoi ...
south of
Peridot.
It emerges from the mountains into the valley southeast of Phoenix, Arizona, where it crosses the
Gila River Indian Reservation
Gila River Indian Reservation was a reservation established in 1859 by the United States government in New Mexico Territory, to set aside the lands of the Akimel O’odham (Pima) and the Piipaash (Maricopa) people along the Gila River, in what ...
as an intermittent
stream
A stream is a continuous body of water, body of surface water Current (stream), flowing within the stream bed, bed and bank (geography), banks of a channel (geography), channel. Depending on its location or certain characteristics, a stream ...
due to large
irrigation
Irrigation (also referred to as watering) is the practice of applying controlled amounts of water to land to help grow Crop, crops, Landscape plant, landscape plants, and Lawn, lawns. Irrigation has been a key aspect of agriculture for over 5,00 ...
diversions, primarily at the Hayden Ashurst Diversion Dam. Well west of Phoenix, the river bends sharply southward along the Gila Bend Mountains, then it swings westward again near the town of
Gila Bend
Gila Bend (; O'odham: Hila Wi:n), founded in 1872, is a town in Maricopa County, Arizona, United States. The town is named for an approximately 90-degree bend in the Gila River, which is near the community's current location. As of the 2020 cen ...
. It flows southwestward between the
Gila Mountains to the south and the
Languna and
Muggins
Muggins, sometimes also called All Fives, is a domino game played with any of the commonly available sets. Although suitable for up to four players, Muggins is described by John McLeod as "a good, quick two player game". ranges to the north in
Yuma County, and finally it empties into the Colorado at
Yuma, Arizona
Yuma ( coc, Yuum) is a city in and the county seat of Yuma County, Arizona, United States. The city's population was 93,064 at the 2010 census, up from the 2000 census population of 77,515.
Yuma is the principal city of the Yuma, Arizona, M ...
.
The Gila is joined by many tributaries, beginning with the East and West Forks of the river, which combine to form the main stem near
Gila Hot Springs in New Mexico. Above Safford, it is joined by the
San Francisco River and the intermittent San Simon River. Further downstream, it is joined by the San Carlos River from the north in San Carlos Lake. At
Winkelman, Arizona
Winkelman is a town in Gila and Pinal counties in Arizona, United States. According to the 2010 census, the population of the town was 353, all of whom lived in Gila County.
History
The community was named after Peter Winkelman, a local catt ...
, it picks up the
San Pedro River and then is joined by the
Santa Cruz River south of
Casa Grande
, settlement_type = City
, image_skyline = Casa Grande-Casa Grande Union High School-1920-2.jpg
, imagesize = 250px
, image_caption = Historic Casa Grande Union High School which now serves as the ...
. The
Salt River, its main tributary, joins in the Phoenix metropolitan area, and further west the Gila receives its last two major tributaries, the
Agua Fria and
Hassayampa Rivers, from the north.
Although the Gila River flows entirely within the United States, the headwaters of two tributaries – the San Pedro and
Santa Cruz Rivers – extend into Mexico. About , or 2.8% of the Gila's watershed, is in Mexico.
A further or 5.7% lies within New Mexico, while the remaining majority, or 91.5%, is in Arizona.
History
A band of
Pima
Pima or PIMA may refer to:
People
* Pima people, the Akimel O'odham, Indigenous peoples in Arizona (U.S.) and Sonora (Mexico)
Places
* Pima, Arizona, a town in Graham County
* Pima County, Arizona
* Pima Canyon, in the Santa Catalina Mountains ...
(autonym "Akimel O'odham", river people), the Keli Akimel O'odham (Gila River People), have lived on the banks of the Gila River since before the arrival of Spanish explorers. Popular theory says that the word "Gila" was derived from a Spanish contraction of Hah-quah-sa-eel, a
Yuma word meaning "running water which is salty". Their traditional way of life (''himdagĭ'', sometimes rendered in English as Him-dak) was and is centered at the river, which is considered holy. Traditionally, sand from the banks of the river is used as an exfoliant when bathing (often in rainstorms, especially during the monsoon).
Indigenous peoples such as the
Hohokam were responsible for creating large, complex civilizations along the Middle Gila River and Salt River between 600 and 1450 AD. These native civilizations depended largely on irrigated agriculture, for which they constructed over of canals. The upper Gila was inhabited by the
Mogollon culture
Mogollon culture () is an archaeological culture of Native American peoples from Southern New Mexico and Arizona, Northern Sonora and Chihuahua, and Western Texas. The northern part of this region is Oasisamerica, while the southern span of the M ...
over most of the same time period, in settlements like those at
Gila Cliff Dwellings National Monument
Gila Cliff Dwellings National Monument is a U.S. National Monument created to protect Mogollon cliff dwellings in the Gila Wilderness on the headwaters of the Gila River in southwest New Mexico. The national monument was established by President ...
in the later period.
The first European to see the Gila River was possibly
Spanish
Spanish might refer to:
* Items from or related to Spain:
**Spaniards are a nation and ethnic group indigenous to Spain
**Spanish language, spoken in Spain and many Latin American countries
**Spanish cuisine
Other places
* Spanish, Ontario, Can ...
explorer and missionary
Juan de la Asunción. Asunción reached the Gila in 1538 after traveling northwards along one of its tributaries, either the San Pedro or Santa Cruz. In 1540,
Hernando de Alarcón
Hernando de Alarcón (born 1500) was a Spanish explorer and navigator of the 16th century, noted for having led an early expedition to the Baja California Peninsula, during which he became one of the first Europeans to ascend the Colorado River ...
sailed up the Colorado and Gila Rivers; maps drawn by his expedition show the river as the ''Miraflores'' or ''Brazos de la Miraflores''.
During the
Mexican–American War
The Mexican–American War, also known in the United States as the Mexican War and in Mexico as the (''United States intervention in Mexico''), was an armed conflict between the United States and Mexico from 1846 to 1848. It followed the 1 ...
, General
Stephen Watts Kearny
Stephen Watts Kearny (sometimes spelled Kearney) ( ) (August 30, 1794October 31, 1848) was one of the foremost antebellum frontier officers of the United States Army. He is remembered for his significant contributions in the Mexican–American Wa ...
marched 100 cavalrymen from the
1st U.S. Dragoons
The 1st Cavalry Regiment is a United States Army regiment that has its antecedents in the early 19th century in the formation of the United States Regiment of Dragoons. To this day, the unit's special designation is "First Regiment of Dragoons ...
along the Gila River in November 1846. This detachment was guided by
Kit Carson
Christopher Houston Carson (December 24, 1809 – May 23, 1868) was an American frontiersman. He was a fur trapper, wilderness guide, Indian agent, and U.S. Army officer. He became a frontier legend in his own lifetime by biographies and ...
. The
Mormon Battalion
The Mormon Battalion was the only religious unit in United States military history in federal service, recruited solely from one religious body and having a religious title as the unit designation. The volunteers served from July 1846 to July ...
followed Kearny's troops, building a wagon trail roughly following the river from December 1846 to January 1847.
After the
Treaty of Guadalupe-Hidalgo in 1848, the Gila River served as a part of the border between the United States and Mexico until the 1853
Gadsden Purchase extended American territory well south of the Gila. The confluence of the Gila with the Colorado River was also used as a reference point for the southern border of California. Beginning in 1871, mainly
Mormon
Mormons are a religious and cultural group related to Mormonism, the principal branch of the Latter Day Saint movement started by Joseph Smith in upstate New York during the 1820s. After Smith's death in 1844, the movement split into several ...
settlers populated the Gila River valley around present-day Phoenix, using the Gila, Salt, and San Pedro Rivers for irrigation and establishing at least six major settlements.
In 1944, 25 German
prisoners of war
A prisoner of war (POW) is a person who is held Captivity, captive by a belligerent power during or immediately after an armed conflict. The earliest recorded usage of the phrase "prisoner of war" dates back to 1610.
Belligerents hold priso ...
pulled off the
largest and most spectacular escape from an American compound during the war, digging a tunnel out of the Navy’s
Papago Park
Papago Park () is a municipal park of the cities of Phoenix and Tempe, Arizona, United States. It has been designated as a Phoenix Point of Pride.
It includes Hunt's Tomb, which is listed on the National Register of Historic Places.
Description
...
Prisoner of War Camp in Arizona. All of the men were eventually captured, though some remained at large for more than a month. Among the last to be captured were three German soldiers who had based their audacious but ill-fated escape plans on a stolen highway map of Arizona, which showed the Gila River leading to the Colorado River, which in turn led to Mexico. Devising a scheme to flee by water, the Germans constructed a collapsible
kayak under the noses of their American captors, tested it in a makeshift pool within the prison compound, then sneaked it out through the tunnel. Their plan was perfect – except for the map. The Gila, shown as a healthy blue waterway, turned out to be little more than a dry rut.
File:McPhaul Suspension Bridge.jpg, The McPhaul Suspension Bridge
The McPhaul Suspension Bridge, sometimes known as Yuma, Arizona's ''Bridge to Nowhere'' is a suspension bridge that used to carry a section of Arizona Route 95 (AZ SR 95, which later became US 95). The bridge is listed on the ...
on a former section of US Route 95 spans the Gila between the Gila and Laguna ranges in Yuma County. The bridge is listed on the National Register of Historic Places
The National Register of Historic Places (NRHP) is the United States federal government's official list of districts, sites, buildings, structures and objects deemed worthy of preservation for their historical significance or "great artistic v ...
.
File:Gila River behind Coolidge Dam1.jpg, The Gila River near Coolidge Dam
The Coolidge Dam is a reinforced concrete multiple dome and buttress dam southeast of Globe, Arizona on the Gila River. Built between 1924 and 1928, the Coolidge Dam was part of the San Carlos Irrigation Project. Coolidge Dam was named after ...
in Arizona
File:Minor drainage divide south of Buckeye Arizona aerial.jpg, This patch of desert south of Buckeye, Arizona
Buckeye is a city in Maricopa County, Arizona, United States, and is the westernmost suburb in the Phoenix metropolitan area. As of the 2020 census the population was 91,502, up from 50,876 in 2010 and 6,537 in 2000. It was the fastest-growin ...
, drains east and west from a minor drainage divide. When they flow, both sides flow to the Gila River.
File:PaintedRock.jpg, Painted Rock Dam in central Arizona, with its usually dry reservoir nearly full after heavy runoff in 2005
Dams and diversions
![Gila River at Komatke Arizona](https://upload.wikimedia.org/wikipedia/commons/6/6f/Gila_River_at_Komatke_Arizona.jpg)
The only major dam on the Gila River is Coolidge Dam, southeast of
Globe, Arizona
Globe ( apw, Bésh Baa Gowąh "Place of Metal") is a city in Gila County, Arizona, United States. As of the 2020 census, the population of the city was 7,249. The city is the county seat of Gila County. Globe was founded c. 1875 as a mining ca ...
, which forms San Carlos Lake. The
Painted Rock Dam crosses the Gila near Gila Bend, although the river is a transient one at that point. The majority of the water is diverted at the Ashurst-Hayden Diversion Dam near
Florence, Arizona
, settlement_type = Town
, image_skyline = Main Street original town-site of Florence Arizona National Register of Historic Places.jpg
, imagesize =
, image_caption = Main Street of the original town ...
. A number of minor
diversion dams have been built on the river between the Painted Rock Dam and the Coolidge Dam, including the
Gillespie Dam
The Gillespie Dam is a concrete gravity dam located on the Gila River between the towns of Buckeye, Arizona, Buckeye and Gila Bend, Arizona. The dam was constructed during the 1920s for primarily irrigation purposes. It was key to the developmen ...
, which was breached during a flood in 1993.
Many dams have been built on tributaries to the Gila River, including
Theodore Roosevelt Dam
Theodore Roosevelt Dam is a dam on the Salt River located northeast of Phoenix, Arizona. The dam is high and forms Theodore Roosevelt Lake as it impounds the Salt River. Originally built between 1905 and 1911, the dam was renovated and expande ...
,
Horse Mesa Dam
The Horse Mesa Dam is a concrete thin arch dam located in the Superstition Mountains, northeast of Phoenix in Maricopa County, Arizona.
The dam is long, high and was built between 1924–27. The dam includes three conventional hydroelectric ge ...
, and
Mormon Flat Dam
The Mormon Flat Dam is a dam on the Salt River located Northeast of Phoenix, Arizona.
The dam is 380 feet long, 224 feet high and was built between 1923–25. It is named after nearby Mormon Flat, a place where Latter-day Saints (Mormon) settl ...
on the
Salt River,
New Waddell Dam
The New Waddell Dam is an embankment dam on the Agua Fria River in Maricopa County, Arizona, northwest of Phoenix. It serves as part of the Central Arizona Project (CAP) while also providing water for the Maricopa Water District. The dam create ...
on the
Agua Fria River
The Agua Fria River (Spanish for "cold water") is a long intermittent stream which flows generally south from east-northeast of Prescott in the U.S. state of Arizona. Prescott draws much of its municipal water supply from the upper Agua Fria w ...
, and
Bartlett Dam
The Bartlett Dam is a concrete multiple-arch buttress dam on the Verde River, located 50 km northeast of Phoenix, Arizona. The dam creates Bartlett Lake and its primary purpose is irrigation water supply. It was the first dam constructed on th ...
on the
Verde River
The Verde River ( Yavapai: Haka'he:la) is a major tributary of the Salt River in the U.S. state of Arizona. It is about long and carries a mean flow of at its mouth. It is one of the largest perennial streams in Arizona.
Description
The ...
.
Many major dams in the Gila River system were built and operated by the
U.S. Bureau of Reclamation, which also constructed most of the large dams throughout the Colorado River basin. Others, such as Coolidge Dam, are owned by local water supply agencies, irrigation districts, or Native American tribes.
The Gila River and its main tributary, the Salt River, were both perennial streams carrying large volumes of water – the Gila was once navigable by large riverboats from its mouth to near Phoenix, and by smaller craft from Phoenix nearly to the Arizona-New Mexico border – until irrigation and municipal water diversions turned both into usually dry rivers which carry water only after local downpours create flooding. Below Phoenix to the Colorado River, the Gila is usually either a trickle or completely dry, as is also the lower Salt from
Granite Reef Diversion Dam
The Granite Reef Diversion Dam is a concrete diversion dam located Northeast of Phoenix, Arizona. It impounds the Salt River for irrigation purposes.
The dam diverts nearly all water from the Salt River into the Arizona and South Canals, wh ...
downstream to the Gila, but both rivers can carry large volumes of water following rainfall.
The historic width of the Gila River varied from with a depth of . Its natural discharge was roughly per year, with a mean flow of about at the mouth. The river's present discharge near the mouth is less than per year, with an average flow of just .
Overdraft from the Gila River system prompted the construction of the
Central Arizona Project
The Central Arizona Project (CAP) is a 336 mi (541 km) diversion canal in Arizona in the southern United States.
The aqueduct diverts water from the Colorado River to the Bill Williams Wildlife Refuge south portion of Lake Havasu ne ...
, which delivers some annually from the Colorado River to supplement water supplies in the basin.
The upper Gila River, including its entire length within New Mexico, is a free-flowing one. Recent efforts to allow for damming or otherwise diverting this stretch have met with stiff political resistance, having been named as one of the nation's most endangered rivers due to proposed dam projects such as
Hooker Dam. During his time in office, former New Mexico Governor
Bill Richardson
William Blaine Richardson III (born November 15, 1947) is an American politician, author, and diplomat who served as the 30th governor of New Mexico from 2003 to 2011. He was also the U.S. Ambassador to the United Nations and Energy Secretary ...
had promised to block any such attempt during his term, and he had even considered pushing for a statutory prohibition against any such projects on the state's portion of the river.
Recreation
The Gila River between
Virden, New Mexico
Virden is a village in Hidalgo County, New Mexico, United States. The population was 152 at the 2010 census. Growth and new construction is almost non-existent, but together with the Arizona sister-village of Duncan to the west, the consolidated ...
, and
Solomon, Arizona, is navigable during spring snowmelt and after summer and autumn storms. The river passes through many scenic canyons and stretches of Class I to III whitewater. Due to its desert surroundings, the river is characterized by erratic flows and flash floods that reach high peaks and drop off just as quickly. The Gila's Salt River tributary has even more difficult whitewater, ranging up to Class IV in places, and often has higher and more dependable flows than the Gila.
Boating and fishing are popular on San Carlos Lake and other basin reservoirs, including
Lake Pleasant and
Theodore Roosevelt Lake
Theodore Roosevelt Lake (usually called Roosevelt Lake, sometimes Lake Roosevelt) is a large reservoir formed by Theodore Roosevelt Dam on the Salt River (Arizona), Salt River in Arizona as part of the Salt River Project (SRP). Located roughly 8 ...
. The river system has 36 fish species,
[Benke and Cushing, p. 531] including
largemouth bass
The largemouth bass (''Micropterus salmoides'') is a carnivorous freshwater gamefish in the Centrarchidae ( sunfish) family, a species of black bass native to the eastern and central United States, southeastern Canada and northern Mexico, but ...
,
sunfish,
channel catfish
The channel catfish (''Ictalurus punctatus'') is North America's most numerous catfish species. It is the official fish of Kansas, Missouri, Iowa, Nebraska, and Tennessee, and is informally referred to as a "channel cat". In the United States, the ...
,
flathead catfish
The flathead catfish (''Pylodictis olivaris''), also called by several common names including mudcat or shovelhead cat, is a large species of North American freshwater catfish in the family Ictaluridae. It is the only species of the genus '' ...
, and
Gila trout
The Gila trout (''Oncorhynchus gilae'') is a species of salmonid, related to the rainbow, native to the Southwest United States. Prior to 2006 the Gila trout was federally listed as endangered. In July 2006, after much work by the Game and Fish ...
''(Oncorhynchus gilae gilae)''.
File:Gila River Middle Fork.2.jpg, Middle Fork of the Gila River, SW New Mexico
File:Spires, E Fork Gila R.jpg, Rock spires above the East Fork of the Gila River, Gila Wilderness
Gila Wilderness was designated the world's first wilderness area on June 3, 1924. Along with Aldo Leopold Wilderness and Blue Range Wilderness, the 558,014 acre (225,820 ha) (872 sq. mi.) wilderness is part of New Mexico's Gila National Forest. ...
Variant names
The Gila River has also been known as:
* Akee-mull
* Apache de Gila
* Brazo de Miraflores
* Cina`ahuwipi (
Chemehuevi language
Colorado River Numic (also called Ute , Southern Paiute , Ute–Southern Paiute, or Ute-Chemehuevi ), of the Numic branch of the Uto-Aztecan language family, is a dialect chain that stretches from southeastern California to Colorado. Individual ...
)
* Hah-quah-sa eel (
Yuma language)
* Hela River
* Jila River
* Rio Azul
* Rio Gila
* Rio de las Balsas
* Rio del Nombre Jesus
* Rio del los Apostoles
* Zila River
* Xila River
* Keli Akimel
See also
*
Gila and Salt River Meridian
*
Gila River War Relocation Center
The Gila River War Relocation Center was an American concentration camp in Arizona, one of several built by the War Relocation Authority (WRA) during the Second World War for the incarceration of Japanese Americans from the West Coast. It was lo ...
*
List of Arizona rivers
List of rivers in Arizona (U.S. state), sorted by name.
By drainage basin
This list is arranged by drainage basin, with respective tributaries indented under each larger stream's name.
Colorado River
*Colorado River—(downstream-to-upstr ...
*
List of New Mexico rivers
A ''list'' is any set of items in a row. List or lists may also refer to:
People
* List (surname)
Organizations
* List College, an undergraduate division of the Jewish Theological Seminary of America
* SC Germania List, German rugby unio ...
*
List of longest rivers of the United States (by main stem)
The longest rivers of the United States include 38 that have main stems of at least long. The main stem is "the primary downstream segment of a river, as contrasted to its tributaries". The United States Geological Survey (USGS) defines a main- ...
*
List of tributaries of the Gila River
*
Needle's Eye Wilderness
*
San Francisco River
*
San Pedro River
*
Santa Cruz River
References
Citations
Works cited
*
External links
Gila River Tourism WebsiteArizona Boating Locations Facilities MapArizona Fishing Locations MapWhere to Fish in Arizona Species InformationArizona Lake Levels
{{authority control
Arizona placenames of Native American origin
Rivers of Arizona
Rivers of Gila County, Arizona
Rivers of New Mexico
Rivers of Pinal County, Arizona
Rivers of Sierra County, New Mexico
Sonoran Desert
Tributaries of the Colorado River in Arizona
Tributaries of the Lower Colorado River in Arizona