WSP05341

• File Number: 8278.100
• Description: Title I - Yuma Desalting Plant
• Basin: Colorado Mainstem
• Date: 12/23/1992
• Author: USDOI/BOR
• Title: Yuma Desalting Plant - Alternatives for the Interim Period
• Water Supply Pro - Doc Type: Publication

I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I

ALTERNATIVE E1: Non-Federal Funding Of Operation. Under this alternative, the
Desalting Plant would be maintained in standby mode at Federal expense
($10.6 million per year) during the interim period and operated at up to fu"-
scale capacity, provided that non-Federal entities were willing to provide a
proportionate share of the costs. During the interim period, the water
conserved from lining the Coachella Canal, combined with irrigation management
improvements, would be used to replace the additional water released from
storage to meet the delivery obligation to Mexico during the interim period.
Purchased desalted water would be made available, through exchange, for use by
the purchasing entity outside of its entitlement to Colorado River water or
"banked" for future use.

The Lower Basin water users would gain access to a temporary supply of up to
78,500 af per year of water. Water users in both California and Nevada could
utilize the additional supply to offset temporary shortage situations until
their longer-term supply projects are implemented. Drainage water that would
otherwise be lost from use could be recovered by desalting and made available
through exchange as a water supply which was over and above the Lower Basin's
7.5 million af entitlement. However, this interpretation may need the support
of the Basin States, and water users may not be willing to pay the high costs.

Further, concurrence by the Basin States would probably only occur if they
felt that there was a high probability that the reservoir system would refill
and that any water conserved by the operation of the Desalting Plant and
retained in reservoir storage would otherwise likely be lost from potential
use due to reservoir system spill. Absent this high probability of refil"
the Basin States would argue that this alternative does not conserve drainage
water, to be.used in meeting the delivery obligation to Mexico, as envisioned
by the Desalting Plant authorizing Act.

ALTERNATIVE E2: Fu71-Scale Operation. As a surplus to Mexico has not been
declared and is unlikely during the next few years, the Secretary would
operate the Desalting Plant and reduce the loss of irrigation drainage in
meeting the delivery obligation to Mexico during the interim period.
Additional water conserved by the Coachella Canal lining during the remainder
of the interim period would be credited against future obligations of the
United States to replace the reject stream from the Desalting Plant. This
alternative would require $33.7 million per year of Federal funds.

The Basin States would argue that Congress authorized and appropriated funds
for construction consistent with the authorizing Act so as not to diminish
water appropriated to the Basin States in meeting the 1944 Treaty obligations
to Mexico and that Congress intended for the Desalting Plant to be operated
once construction was completed for conservation of the water of the Basin
States. Mexico is likely to support full-scale operation because it enhances
the likelihood of surplus deliveries to Nexico.

PREFERRED PLAN OF ACTION:

OPERATE AT PARTIAL CAPACITY /11TH OPTION FOR NON-FEDERAL FUNDING OF A/JDITIONAL
CAPACITY - Under the preferred plan, the Desalting Plant would continue to be
operated at one-third capacity using Federal funding during the interim

vii