WSPC05946

• File Number: 8272
• Description: Colorado River - Colorado River Basin Salinity Control Program - CRBSCP
• State: CO
• Basin: Colorado Mainstem
• Water Division: 5
• Date: 10/10/1996
• Title: Proposed Supplemental Report on the Water Quality Standards for Salinity - Colorado River System - 1996 Review - Draft
• Water Supply Pro - Doc Type: Report/Study

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OPERATING HEAOQUARTERS . POBOX 937 . IMPERIAL. CALIFORNIA 92251

Sep\cmber 3, 1996

Mr. Jack A. Barnett
Executive Director
Colorado River Basin Saliniiy Control Forum
106 West 500 South, Suite 101
Bountiful, Utah 84010

Subject: Comments-1996 Review oJWater Quality Standards Jar Salinity, Colorado River System
H,n~..::l.t",k-~
Dear ~ett

.

,
The Imperial Irrigation District (lID) has examined 1he 1996 Review oJ Waler Quality Standards Jor Salinity.
Colorado River System (Review), dated June 1996, and appreciates being given the opportuniiy to comment on
this document. As the most southerly user of Colorado River waters \\1thin the United Slates, the 110 is a
primary beneficiary of Colorado River saliniiy control measures and sincerely supports the efforts of the
Colorado River Basin Saliniiy Con1rol Forum (Forum). The lID concurs with the general recommendations sct
forth in this Review, and supports the saliniiy con1rol measures the Forum has advoca1ed to achieve current and
future standards. At this time, the 110 also con1inues to endorse the existing numerie Colorado River saliniiy
cri1eria and encourages the attairuncnt of these large! levels.

However, as the largest and most downstream user of Colorado River wa1ers in both California and the Lower
Basin, it is imperative to the 110 that the saliniiy con1rol programs noted in this Review not only be implemented,
but placed on an accelerated schedule as well. The 110 and its agricultural users continue to be damaged due to
the increasing saliniiy of the Colorado River, both by econornic losses and the requirement to use more water to
sustain an acccplable sail balance. If the current scheduling of planned projects is n01 expedi1ed, the likelihood of
fuiling to meet targeted saliniiy standards becomes not only a danger, but a rcaliiy. According to this Review,
when existing obserllcd saliniiy levels are adjusted to reflect the full impact of the current level of water
development within the basin (1ong-tenn mean water supply), these adjustcd saliniiy concentrations exceed the
Forum's nwnerie criteria a1 all three measurement stations. Of particular concem to the lID are the saliniiy levels
at Imperial Dam (lID's point of diversion), but we obviously have a vested interest in water qualiiy at the two
upstream stations as well.

I

Wlule the goal of the Colorado River Basin Saliniiy Control Program (Program) is ultimately a 1.48 million ton
reduction in the sail loading of the Colorado River, the liD does not feel that dIe pace of the current schedule is
adequate to ob1ain dus objective. In fact, based on dIe analysis ouilined in this Review, the 1995 Program
"backlog" involves con1rols thai would reduce Colorado River saliluiy by more than 418,000 tons. 1l1.is is in
addition to future controls designed to lower 1he River's salt load by 437,000 tons over dIe next tweniy years.
Thus, according to the Review, this translates 10 a need for "45,000 tons of new saliniiy control measures. . each
year. . . (until) 2015." Given the current slatus and recent funding trends of the Program, the lID does not feel
that adequate efforts are being put forth to implement additional saliniiy control projects. The lables that provide
exccedance evaluation analyses for the three measurement stations in the Review further illustra1e this point. The
te,,'! in Appendix C notes that, \viill only dle existing salinity controls in place, '"there is a (sic) 18 percent chance

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