Supplemental Environmental Impact Statement for Near-term Colorado River Operations

The Secretary of the Interior has directed Reclamation to prepare a SEIS to the December 2007 Record of Decision associated with the Colorado River Interim Guidelines for Lower Basin Shortages and Coordinated Operations for Lake Powell and Lake Mead, referred to as the 2007 Interim Guidelines.

The announcement is contained in the agency's Notice of Intent To Prepare a Supplemental Environmental Impact Statement for December 2007 Record of Decision Entitled Colorado River Interim Guidelines for Lower Basin Shortages and Coordinated Operations For Lake Powell and Lake Mead and includes additional information about the purpose and need for the SEIS, alternatives, and public involvement opportunities.

In-Depth

The Colorado River Mid-term Modeling System (CRMMS) model environment that includes the model, inputs, and results relied on to produce the scenarios presented at the November 29 and December 2 SEIS scoping webinars is available upon request, please contact Alan Butler at rabutler@usbr.gov.

Related Links

Purpose and Need

Through this Notice , Reclamation is initiating efforts to revise operating guidelines for the operation of Glen Canyon and Hoover Dams in 2023-24 operating years in order to address the potential for continued low-runoff conditions in the Colorado River Basin. Reclamation has concluded that the potential impacts of low runoff conditions in the coming winter (2022-2023) pose unacceptable risks to routine operations of Glen Canyon and Hoover dams during the interim period (prior to Jan. 1, 2027) and accordingly, modified operating guidelines need to be expeditiously developed.

Public Involvement

Reclamation hosted two public webinars to summarize the content and purpose of this Federal Register notice and provide additional information about the Supplemental Environmental Impact Statement.

The webinars took place:


Tuesday, November 29, 2022


Friday, Dec. 2, 2022

The SEIS scoping comment period closed on December 20, 2022. Written comments that were submitted by December 20, 2022, will be reviewed and posted on this website.

The draft supplemental EIS is anticipated to be available for public review in Spring 2023 and the final supplemental EIS is anticipated to be available for with a Record of Decision, as appropriate, in late Summer 2023. This schedule will allow decisions to become effective for 2023-2024 operations.

The draft SEIS will be posted here when it is available for public review.

Summary of SEIS Scoping Input Received

Reclamation received comment letters in response to the Notice of Intent to prepare the SEIS for the Dec. 2007 Record of Decision entitled Colorado River Interim Guidelines for Lower Basin Shortages and Coordinated Operations for Lake Powell and Lake Mead.

Links to submissions are available in alphabetical order below:

Additional Information

As noted in its Federal Register notice published in June 2022, Reclamation anticipates initiating a NEPA process for development of operating guidelines for Post-2026 Operational Strategies through a Notice of Intent to Prepare an Environmental Impact Statement in early 2023. Nothing in this notice modifies Reclamation's efforts in that upcoming process.

The need for a SEIS and modified operating guidelines for the period prior to 2026 is a recognition that the risks facing the Colorado River Basin are unacceptably high and cannot wait until post-2026 operational strategies are thoroughly identified, analyzed and ultimately adopted. In addressing operations for 2023-2024, Reclamation is committed to using the best available information to develop near-term operating guidelines while longer term approaches are developed. Reclamation anticipates utilizing the work of this DEIS to also inform operating guidelines for the 2025-26 period, which will also undergo NEPA analysis in the near future.

QUESTIONS?

Questions regarding the SEIS for potential modifications to near-term Colorado River operations may be directed to:

Dedina Williams, dfwilliams@usbr.gov

Marcie Bainson, mbainson@usbr.gov

Last Updated: 2/1/23