WSP02976

• File Number: 8271.300
• Description: Colorado River Basin Salinity Control Program - General Information and Publications-Reports
• Basin: Colorado Mainstem
• Water Division: 5
• Date: 12/1/1979
• Title: An Economic Evaluation of the Salinity Impacts From Energy Development - The Case of the Upper Colorado River Basin
• Water Supply Pro - Doc Type: Report/Study

laken into account, the results of these two
(.I.' studies yield essentially the same estimates
f\J of average annual flows.

1-'

~ Cases for model analysis

The most accepted inlerpretations of the
legal and institutional constraints and
a ssumpt ions of ava i lable water supply were
used to construct five cases for analysis
(Table 6). From the net state shares in
Table 6, municipal, industrial, and other
consumptive uses are subtracted to estimate
the net water available for energy or agri-
culture in Table 7. In each case, the total

water depletions must be less than a state's
compact entitlement.

Case l. Th is case takes the mas t
optimIstiC-view of the available water supply
using the long term average of l4.994 t>lAF.
From this is deducted the Lower Basin share
of 7.5 MAF, half of the Mexican Treaty
obligation of 0.75 MAF, and 0.05 MAF for
Arizona's entitlement (a total of 8.3 MAF) to
leave 6.694 MAF to apportion by the percent-
ages for the Upper Basin states. The final
figur~ for water availability for energy
and agriculture for 1975, 1985, and 2000 is
obtained by subtracting all other projected
uses from the state apportionment.

Table 6. Water shares of Upper Basin States under different supply and institutional
assumptions (AF x l03).

States
Basin Colorado New Mexi co Utah Wyom; ng
Total (51.75%) (11.25%) (23.00%) (14.00%)
CASE 1
Average Annual Flow 14,994a
Lower Basin Share 8,300
Upper Basin Shares 6,694 3464 753 1540 937
Main Stem Evaporation 520 269 58 120 73
Net State Shares 6,174 3195 695 1420 364
CASE 2
Average Annual Flow 14,000
Lower Basin Share 7,550b
Upper Basin Shares 6,450 3338 726 1483 903
Main Stem Evaporation 520 269 58 120 73
Net State Shares 5,930 3069 668 1363 830
CASE 3
Average Annual Flow 14,050
Lower Basin Share 8,300c
Upper Basin Shares 5,750 2976 647 1322 805
Main Stem Evaporation 520 269 58 120 73
Net State Shares 5,230 2707 589 1202 732
CASE 4 13,800d
Average Annual Flow
Lower Basin Share 8,300
Upper Basin Shares 5,500 2846 619 1265 770
Main Stem Evaporation 520 269 58 120 73
Net State Shares 4,980 2577 561 1145 697
CASE 5
Average Annual Flow 13,800
Lower Basin Share 7,550
Upper Basin Shares 6,250 3234 703 1437 875
Main Stem Evaporation 520 269 58 120 73
Net State Shares 5,730 2965 645 1317 802
aLower Basin ~ 7.5 MAF, Mexi co 0.75 MAF, and Arizona = 0.05 MAF
bUpper Colorado River Commission estimate of 6.5 MAF less 0.05 MAF to Ari zona
CBureau of Reclamation conservative hypothesis of 5.8 MAF less 0.05 MAF to Arizona
dA .. flow since Colorado River Compact (1922-1975)
verage Vl rgln
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