|
<br />
<br />6;
<br />"
<br />~
<br />~.~:)
<br />1"'*
<br />N
<br />
<br />the are~. Agriculture is concentrated along the
<br />mainstr~am in the upper reaches ot the river,
<br />on Silver Creek-a southern tributary-and
<br />on the tuni River in New Mexico. Current ir-
<br />rigated Jcreage is estimated to be about
<br />32,OOO;\however, it is subject to variation
<br />because 'of frequent water shortages and in-
<br />adequat~ storage facilities. Population is pre-
<br />dominantly rural with a relatively large Indian
<br />segment.: Principal cities include Flagstaff,
<br />Winslow, land Holbrook in Arizona, and Gal-
<br />lup and ZlJni Pueblo in New Mexico. Leading
<br />industries; incl!'/de tourism, recreation, manu-
<br />facturing, )mining, and forest products.
<br />
<br />Virgin Riv~,r, Arizona-Utah: The Virgin River
<br />rises in wllstern Kane County, Utah; flows
<br />southwest~rly through the northwestern
<br />corner of Arizona; and empties into the
<br />northern e*remity of the Overton Arm of Lake
<br />Mead in Vitginia. The selected outflow point,
<br />the long-tetm Geological Survey gaging station
<br />at Littlefiel~, Ariz., is about 36 miles upstream
<br />from Lake li\ead and about 10 miles above the
<br />Arizona-Nevada State line. The river is fed
<br />chietly from: tributaries heading in the
<br />southern high plateaus and mountains in
<br />Utah. Sever41 springs contribute water to the
<br />river at a rel~tively uniform rate. The most sig-
<br />nificant of t~ese springs are located near
<br />LaVerkin, Utbh, and Littlefield, Ariz. Both
<br />springs are hlghly saline. Agricultural and
<br />municipal developments in Nevada below
<br />the selected ~utflow point are included in
<br />"remaining ar,eas," as shown on the frontis-
<br />piece map. :
<br />Ground water has been developed to a lim-
<br />ited degree. The major irrigated areas are lo-
<br />cated in the L~Verkin-Hurricane-Santa Clara
<br />areas of Washington County, Utah, and in
<br />I
<br />the Littlefield llrea of Mohave County,
<br />Ariz. There' arfJ small irrigated areas scat-
<br />tered throughout. Present irrigated area is es-
<br />timated to be a~out 28,000 acres. Population
<br />is predominantly rural. St. George, Utah, is the
<br />principal city i~ the basin. Zion National
<br />Park, located n$ar Springdale, Utah, attracts
<br />many visitors eJch year.
<br />Muddy River, Ne~ada: The Muddy River, for-
<br />merly a tributarY of the Virgin River prior to
<br />the existence ofiLake Mead, rises in the warm
<br />
<br />springs area of Clark County, Nev., about 10
<br />miles northwest of Glendale. The river flows
<br />southeasterly for about 30 miles, and termi-
<br />nates at the northern extremity of the Over-
<br />ton Arm of lake Mead. Meadow Valley Wash,
<br />the major tributary of Muddy River, rises in
<br />northeastern Lincoln County and flows south to
<br />join the parent stream at Glendale. The
<br />Geological Survey gaging station near Glendale
<br />is about 2.4 miles downstream from Meadow
<br />Valley Wash. Outflow varies little from year
<br />to year. Meadow Valley Wash, although pe-
<br />rennial in the vicinity of Caliente, is normally
<br />dry in the last 50-mile reach above Glendale.
<br />Estimated irrigated acreage is about 8,900
<br />acres located in the springs area and scattered
<br />throughout the upper reaches of Meadow
<br />Valley Wash. The entire basin is sparsely
<br />populated.
<br />
<br />Bill Williams River, Arizona: The Bill Williams
<br />River is formed by the mergence of the Big
<br />Sandy and Santa Maria Rivers about 7.5 miles
<br />above existing Alamo Dam. The river above
<br />Alamo Dam drains an area of about 4,700
<br />square miles from small, rough mountain
<br />ranges and intervening valleys in parts of
<br />Mohave, Yuma, and Yavapai Counties. Alamo
<br />Dam and Reservoir, a flood control structure
<br />completed in 1968, was built to protect
<br />downstream development along the Colorado
<br />River. A minimum pool is maintained for rec-
<br />reation and game management purposes. Re-
<br />leases from Alamo Dam and runoff from the
<br />intervening area flow westerly and'join the Colo-
<br />rado River at the lower end of lake Havasu. Es-
<br />timated irrigated acreage is about 4,500 acres
<br />with most crops grown to supplement feed for
<br />livestock. The limited development in the basin
<br />is dominated by copper mining at the unincor-
<br />porated town of Bagdad, present population
<br />about 2,000. A large portion of the water
<br />supply in the basin is obtained from ground-
<br />water pumpage. Releases from Alamo Dam
<br />during the 1971-75 period varied from
<br />1,500 acre-feet in 1975 to 162,500 acre-
<br />feet in 1973.
<br />
<br />Gila River, Arizona-New Mexico: The Gila River
<br />is the largest tributary to the Colorado River in
<br />the Lower Colorado River system. The drainage
<br />8
<br />
<br />
|