9674

• UCREFRP Catalog Number: 9674
• Author: Endangered Fish Flow and Colorado River Compact Water Development Workgroup.
• Title: Final Report - Colorado River Compact Water Development Projection.
• USFW Year: 1995.
• USFW - Doc Type: \
• Copyright Material: NO

COLORADO RIVER COMPACT WATER DEVELOPMENT PROJECTION
November 2, 1995 FINAL REPORT EXECUTIVE SUMMARY
Page 1
EXECUTIVE SUMMARY
The CWCB informally convened the ad hoc Endangered Fish Flow and Colorado
River Compact Water Development Workgroup ("Workgroup") to assist in estimating and
protecting the future uses of Colorado's unused compact apportionment in the Colorado River
Basin and to assure that the people of Colorado are not deprived of the beneficial use of those
waters available by law and interstate compact. The Workgroup assisted and provided the
CWCB input on how much water can be appropriated for endangered fish recovery instream
flow purposes within the various sub-basins of the Colorado River basin in Colorado without
impairing Colorado's ability to fully develop its compact apportioned waters. However, the
observations and recommendations contained in this report are not intended to interpret the
provisions of the Colorado River Compact, the Upper Colorado River Basin Compact and
other provisions of the "Law of the Colorado R.iver," the Colorado Constitution or other laws
of the state of Colorado with respect to water rights or their administration in Colorado.
The workgroup first established ground rules and a process for undertaking this
assignment. The workgroup then reviewed; 1) the key documents relating to the "Law of the
Colorado River", 2) Colorado River basin hydrology within the state (10.8 MAF'), 3)
Colorado's compact apportionment under various interpretations of the "Law of the Colorado
River" and the wide variation in hydrologic conditions (between 3.079 and 3.855 MAF); 4)
Colorado's current consumptive uses of water (2.6 MAF maximum adjusted); and 5) the
remaining compact apportionment again given the uncertainties of the law and variations in
hydrology (between .45 MAF and 1.2 MAF at minimum). The workgroup then considered a
variety of alternatives for distributing Colorado's remaining compact apportionment among
the seven major subbasin's within Colorado.
These considerations are described and discussed in this report. This report has been
reviewed by the workgroup on two occasions. In addition, it has also undergone a peer
review for technical accuracy. These reviews resulted in only minor editorial changes,
primarily for improved clarity. There were no substantive changes made to the report.
The Workgroup's recommended approach for distributing Colorado's remaining
compact apportionment among the seven major tributaries is described in Table. 4. In
reviewing Table 4, the Workgroup wishes to emphasize the following observations:
A. We have not recommended any specific distribution to any particular subbasin; nor
have we specifically recognized any particular water rights. Rather, we have established a
recommended range of development allowance for each subbasin as described in Table 4.
The upper limit of these ranges allows upto 3.855 MAF of total consumption from the
Colorado River Basin by distributing up to one-half of the remaining compact apportioned
waters needed to reach the 3.079 MAF level of development to each of the seven major
subbasins but only to the extent that water is physically available for appropriation. The
lower limit of our recommended ranges is based upon the lower estimate of Colorado's
apportionment (i.e., 3.079 MAF), and distributes the state's approximately 450,000 acre feet
of remaining apportionment among the seven major subbasins based on the proportionate