<br />TABLE 4.
<br />
<br />WATER AND SALT BUDGETS, PRESENT CONDITIONS,
<br />VIRGIN VALLEY SUBEVALUATION UNIT, ARIZONA, NEVADA,
<br />Water
<br />Acre-feet/year
<br />
<br />UTAH
<br />
<br />Salt
<br />Tons/year
<br />
<br />1/
<br />Littlefield, Arizona Gage- 220,800
<br />Local Inflow (runoff and groundwater recharge) 12,300
<br />
<br />384,900
<br />
<br />3,300
<br />
<br />Total 233,100
<br />
<br />388,200
<br />
<br />Depletions
<br />
<br />Crop Consumptive Irrigation Use
<br />
<br />-14,100
<br />-12,600
<br />192,400 349,900
<br />14,0001/ 76,10~/
<br />206,400 426,000
<br />-10,400
<br />196,000 426,OOrP
<br />
<br />Phreatophyte Use, Evaporation,
<br />Livestock and Domestic Use, etc.
<br />
<br />. 2/
<br />Surface Flow at Riverside, Nevada Gage-
<br />
<br />Subsurface Flow at Riverside, Nevada
<br />
<br />Outflow From Program Area
<br />
<br />Phreatophyte Use
<br />
<br />Total Outflow to Lake Mead
<br />
<br />1/ Abow Littlefield, Arizona, 319 &cr.. 1D the proll'_ are. ar. irrilated by aurfae. methodl.
<br />S.le budget. for alternative pl~ ar. Biven in Table 9.
<br />1/ Concurrent y..ra of flow and salt recorda ae 'Littlefield, Arizona. and Rin:rI1de, N.....d.,
<br />a.. va.a. y.a.a 1972-1974, 1978 aad 1979.
<br />11 B...d OD computation. for flow anA salinity ....uremeat at the locatioD coaaidered by USSR
<br />for constructioa of . grouad waCer barrier. DtlCualioal in 1980 and 1981 with Robert Barton,
<br />USBR. Boulder City, Nevada, 1Ildicated value. are vitb1D . re.soo.able range.
<br />.il Eat1u.ced salt pick up 18 31,800 tonl ErOll irrigation and other US.., plua 3,300 tona frO'll
<br />local 1nflow.
<br />
<br />Salt Budget - Daily salt loads were calculated for the gage at Little-
<br />field for water years 1972-74, and 1978-79 using the mean daily flow and
<br />daily specific conductance readings published in the USGS Water Resources
<br />Data reports for Nevada. Daily flow and water quality data for the gage
<br />at Riverside are only available for water year 1979. These data were
<br />plotted and relationships developed between them. Daily salt loads for
<br />water years 1972-74 and 1978 were calculated for daily flow measurements.
<br />The calculations show that an average of 384,900 tons of salt flow past the
<br />Littlefield gage while approximately 349,900 tons are carried in surface
<br />flow past the Riverside gage each year, An additional 76,100 tons of salt
<br />are carried by ground water at Riverside based on an average subsurface
<br />flow of 14,000 acre-feet with an average salinity concentration of 4,000
<br />mg/l. The salt budget for the present condition is given in Table 4.
<br />Figure S and S":A illus.trate the water and salt budgets.
<br />
<br />11
<br />
<br />r, ') c, r, l)" 8'
<br />}.' , .
<br />,'... u '-
<br />
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