WSP11698

• File Number: 8210.470
• Description: Pacific Southwest Interagency Committee
• State: CO
• Basin: Colorado Mainstem
• Water Division: 5
• Date: 8/6/1964
• Author: Unknown
• Title: Lower Colorado River Basin Project - Report with Individual and Minority Views - To Accompany S 1658 - Calendar Number 1267
• Water Supply Pro - Doc Type: Report/Study

001792-
8

THE LOWER COLORADO RIVER BASIN PROJECT

Water 8upply for Central Arizona unit

. [Millions of acre-feet]

.
Yea.r-
1990 2000 2020 2030
I. Water'sueP1y availa.ble" to lower basin States:
, AvaUa.b e main, stream supply.(table 16A and
UsnR extension) ~~_~____________________________ 7.155 6.68 6.38 6.30
... .
.II., Main stream requirements (table 13 and USBR
extensions, California, limited to 4.4):
Arizona. (exclusive of Central Arizona.)l________ 1.27 1.27 1.27 1.27
. Nevada J_:..__~.________________________________ .17 .20 .30 .30
California.. _ _ _______________.'._________________ 4.40 4.40 4.40 4.40
Total, main stream requirements____________ 5.84 5.87 5.97 5.97
III. SUPflY available to Central Arizona unit:
, A) wf;~~~r~fr,.~~~~i~:~::_~=_=:_~~~_~~:l~_ 1.32 .8l .41 .33
(B) 25-year priority of 4.4 followed by prora.
Uon using special master's formula:
Arizona's share '1'__-_____________R___'___ 2.67 2.49 2.38 2.35
Arizona USGS in IL~h_~________u_____ 1.27 1.27 1.27 1.27
A vaUable to Central Arizona uniL.~ 1.40 1.22 1.11 1.08

1 Inclusive use ,of increased Indian and main stream fish and wildlife uses.
,2,28/15 ?r37.33 ~cent of water ~~ppIY in 1.

. Source: Pacific Southwest wa,te'i pIau, Jamiary 1964.

Neither method of allocation of shortage is fully acceptable to the
lisers of the lower basin although a proration of shortage during
periods of adverse hydrology would permit all users a basis of con-
tinued existence until more water could be brought in. Neither
method moreover can be regarded as a suitable substitute for the
development of additional water which must be provided. In this
connection, however, the committee stresses that the most readily
available and cheapest source of supplemental water is by exercising
better husbandry of the supplies already available to the lower basin.
Major canal lining pJ;ojects in Oalifornia and Arizona are indicated and
if installed, with other conservation measures, would go far in cushion-
ing the impact of low runoff. Estimates of the possible savings from
canal linings alone run to as much as a million acre-feet per year. The
committee was impressed by graphic information presented during the
hearings indicating the extent of potential water salvage opportu-
nities in the basin.
Nevertheless, these off-river canal lining programs, while most
important in adding to the supply of water in each State to meet
future needsz will not relieve the shortage of :flow in the lower 0010-
rado River Itself, nor, therefore, will they relieve the necessity to
d(jvelop additional water that can be brought in to meet the 7.5 million
acre-foot contract demand on the main stream.
It is obvious that if the Oalifornia proposal were applied in per-
petuity, there would be no dependable water supply for the Oentral
Arizona project. This led the committee to adopt the compromise
described herein under section 104 of the section-by-section analysis.

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