The Secretary of the Interior - Washington - CO River Interim Guidelines for Lower Basin Shortages and the Coordinated Operations for Lake Powell and Lake Mead

• Year: 2007
• Title: The Secretary of the Interior - Washington - CO River Interim Guidelines for Lower Basin Shortages and the Coordinated Operations for Lake Powell and Lake Mead
• CWCB Section: Interstate & Federal
• Description: The Secretary of the Interior - Washington - CO River Interim Guidelines for Lower Basin Shortages and the Coordinated Operations for Lake Powell and Lake Mead
• Publications - Doc Type: Other

Interim Guidelines for the
Operation of Lake Powell
and Lake Mead
and navigation, and sport fish populations), transportation, socioeconomics (including
employment, income and tax revenue, municipal and industrial water users, and
recreation economics), environmental justice, indirect effects of the ICS mechanism,
and climate change considerations. The potential effects to specific resources were
identified and analyzed for each action alternative and compared to the potential effects
to that resource under the No Action Alternative. These comparisons are typically
expressed in terms of the relative differences in probabilities between the No Action
Alternative and the action alternatives.
Based on the analyses in the EIS, Reclamation determined that specific measures to
avoid or mitigate environmental harm were not required, with the exception of
conservation measures for listed species as noted below. For other resource areas, the
impacts of the Preferred Alternative were well within the range of the alternatives
considered, and generally improved conditions compared to the No Action Alternative.
For a few resource areas, the Preferred Alternative resulted in minor negative impacts
compared to the No Action Alternative, and measures to avoid such impacts were
determined to be unnecessary or not feasible.
A. Lower Colorado River Multi-Species Conservation Plan
It is important to note that Reclamation is already undertaking significant
environmental mitigation measures on the Colorado River, including the LCR
MSCP from Lake Mead to the Southerly International Boundary (SIB) with Mexico,
and implementation of activities pursuant to the 1996 Glen Canyon Dam ROD for
the reach of the Colorado River from Glen Canyon Dam to Lake Mead.
The LCR MSCP is a 50-year cooperative effort between federal and non-federal
entities, approved by the Secretary in April 2005. This program was developed to
address potential effects to listed and other selected special status species (covered
species) from identified ongoing and future anticipated federal discretionary actions
and non-federal activities on the lower Colorado River (covered actions). The
development and implementation of shortage criteria on the lower Colorado River
was one of the federal covered actions (MSCP Biological Assessment Section
2.2.2.1) included in the LCR MSCP and covered under the LCR MSCP BO (FWS
2005). The LCR MSCP BO provides Endangered Species Act (ESA) compliance
for the effects of covered actions for a reduction of Lake Mead reservoir elevations
to 950 feet msl and flow reductions of up to 0.845 maf from Hoover Dam to Davis
Dam, 0.860 maf from Davis Dam to Parker Dam, and 1.574 maf from Parker Dam
to Imperial Dam. The LCR MSCP identified, and it is mitigating for, impacts to the
covered species and their habitats from the flow reduction conditions described
above. These impacts included the potential loss of up to:
• 2,008 acres of cottonwood-willow habitats;
• 133 acres of marsh habitat; and
ROD -Colorado River Interim Guidelines for December 2007
Lower Basin Shortages and Coordinated 17
Operations for Lake Powell and Lake Mead