9318

• UCREFRP Catalog Number: 9318
• Author: U.S. Fish and Wildlife Service.
• Title: Procedures for Stocking Nonnative Fish Species in the Upper Colorado River Basin.
• USFW Year: 1996.
• USFW - Doc Type: Denver.
• Copyright Material: NO

ranged between 1 ,000 cfs and 25,000 cfs, with flows averaging between 5,000
cfs and 20,000 cfs.
As a result of construction of Glen Canyon Dam, the Colorado River
ecosystem below the dam has changed significantly from its pre-dam natural
character. In addition, the dam's highly variable flow releases from 1964 to 1991
caused additional concern over resource degradation resulting from dam operations.
The Secretary of the Interior adopted interim operations criteria in October 1991
which narrowed the range of daily powerpiant fluctuations. Since the signing of the
operating criteria in February 1997, these releases do not now exceed 25,000 cfs,
and most often average between 10,000 cfs and 20,000 cfs.
Responding to concerns that changes to the Colorado River ecosystem
were resulting from dam operations, Reclamation launched the Glen Canyon
Environmental Studies program in 1982. The research program's first phase (1982-
1988) focused on developing baseline resource assessments of physical and biotic
resources. The second program phase (1989-1996) expanded research programs
in native and non-native fishes, hydrology and aquatic habitats, terrestrial flora and
fauna, cultural and ethnic resources, and social and economic impacts.
By the late 1980s, sufficient knowledge had been developed to raise
concerns that downstream impacts were occurring and that additional information
needed to be developed to quantify the effects and to develop management actions
that could avoid and/or mitigate the impacts. This collective information, and other
factors, led to a July 1989 decision by the Secretary to direct Reclamation to
prepare an environmental impact statement (EIS) on the operation of Glen Canyon
Dam. The intent was to evaluate alternative operation strategies to lessen the
impacts of operations on downstream resources.
In October 1992, the President signed into law the Reclamation Projects
Authorization and Adjustments Act., Public Law (P.L.) 102-575. Responding to
continued concerns over potential impacts of Glen Canyon Dam operations on
downstream resources, Congress included the Grand Canyon Protection Act (GCPA)
as Title 18 of the Reclamation Projects Act. Section 1802(a) of the GCPA requires
the Secretary to operate Glen Canyon Dam:
... in accordance with the additional criteria and operating plans
specified in Section 1804 and exercise other authorities under
existing law in such a manner as to protect, mitigate adverse
impacts to, and improve the values for which Grand Canyon
National Park and Glen Canyon National Recreation Area were
established, including, but not limited to natural and cultural
resources and visitor use.
The GCPA directs the Secretary to implement this section in a manner fully
consistent with all existing laws that govern allocation, appropriation, development,
and exportation of the waters of the Colorado River Basin.
Section 1804 of the GCPA required preparation of an EIS, adoption of
operating criteria and plans, reports to Congress, and allocation of costs. The
Operation of Glen Canyon Dam Final Environmental Impact Statement was filed with
the Environmental Protection Agency (EPA) in March 1995 and a Record of Decision
(ROD) was signed in October 1996. The ROD changed only two flow parameters
32