7423

• UCREFRP Catalog Number: 7423
• Author: U.S. Bureau of Reclamation.
• Title: Glen Canyon Environmental Studies Draft Report, September 1987.
• USFW Year: 1987.
• USFW - Doc Type: Washington, D.C.
• Copyright Material: NO

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The Major Operational Goal For Glen Canyon Dam Is
Water storage And Delivery To The Lower Basin

Two of the objectives identified in the legislation
authorizing the CRSP are most pertinent to the
operation of Glen Canyon Dam: (1) providing water
storage and regulation for irrigation and beneficial
consumptive use, and (2) satisfying water delivery re-
quirements to the Lower Basin, as defined in the
Colorado River Compact. All other project purposes,
including the generation of hydroelectric power, are
incidental to these goals.

The primary purpose of Glen Canyon Dam in the CRSP is
to enable the Upper Basin states (Utah, Colorado,
Wyoming, and New Mexico) to utilize their apportionment
of Colorado River water and meet their obligations for
water delivery to the states of the Lower Basin
(Arizona, Nevada, and California). The reservoir (and
others in the CRSP system) allows the Upper Basin
states to take water year-round from the Upper Colorado
River. for consumptive uses and still store enough
spring runoff in Lake Powell to guarantee the required
delivery to the Lower Basin states even during a long
period of drought.

The operating criteria, administered by the Secretary
of the Interior, define the minimum annual release to
the Lower Basin to be 8.23 maf. Releases greater than
8.23 maf annually are permitted if: (1) storage in
Upper Basin reservoirs is greater than that required by
section 602(a) of the Colorado River Basin Project Act,
and (2) the volume of storage in Lake Powell is greater
than that in Lake Mead. Releases may also be made to
avoid anticipated spills (bypassing the powerplant)
from Glen Canyon. Each of these criteria will be dis-
cussed in turn.

Minimum release of 8.23 maf. Glen Canyon Dam must be
operated such that a minimum of 8.23 maf is released to
the Lower Basin each year (monthly distribution of
volume is not specified). If this release cannot be
met by the CRSP system of reservoirs, the Upper Basin
water users must curtail water use SUfficiently to
allow this delivery.

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