FERC Issues Comments on Temporary Bypass for Georgetown Forebay Dam

Strategic Insights -

The Federal Energy Regulatory Commission (FERC) has issued comments on the proposed temporary bypass for the Georgetown Forebay Dam, part of the Georgetown Project (FERC No. 2187). The commission's response is based on a review of the submittal by Xcel Energy, including drawings, specifications, design criteria, and quality control and inspection plans. FERC has identified several concerns and requested revisions to ensure compliance with dam safety regulations.

Key Takeaways:

  • FERC has raised concerns about the access road to the site, citing its narrow and steep nature, which may require special accommodations, including coordination with the Town of Georgetown.
  • The commission has requested protective measures to prevent erosion of the dam in case the bypass at the abutment contact is ruptured.
  • FERC has asked Xcel Energy to provide supporting documentation for the assumed drained friction angle used in the design of pile foundations and fill materials.
  • The commission has requested a contingency plan for supporting steel sheet pile diversion walls if the minimum pile embedment is not achieved during construction.
  • FERC has highlighted the need for additional discussion regarding anticipated depths of excavation, minimum bearing capacity requirements, and acceptable foundation improvement methods.
  • The commission has asked for a rationale on why a relative compaction requirement is not specified for placement of embankment and structural fills.
  • FERC has requested that Xcel Energy remove detailed contractor information from the Quality Control and Inspection Plan (QCIP) and replace it with general roles, responsibilities, and reporting hierarchy.
  • The commission has asked for a grading plan that provides sufficient detail to grade the South Clear Creek Diversion Channel.
  • FERC has requested a description of public safety improvements, such as signage, that will be installed at the temporary structures.
  • The commission has asked for the results of testing performed during construction to confirm the assumed properties of earth materials for sheet pile wall design.
  • FERC has requested descriptions of changes to the Dam Safety Surveillance and Monitoring Plan that will be implemented to include the temporary structures.
  • The commission has asked for resumes for all personnel with stop work authority, including Xcel personnel.

Statistics:

  • 12 comments have been issued by FERC on the proposed temporary bypass for the Georgetown Forebay Dam.
  • The access road to the site is approximately 1 mile long and features 5 switchbacks.
  • The temporary bypass will extend 250 feet along the downstream left abutment.
  • The minimum pile embedment requirement for steel sheet pile diversion walls is 5 feet.
  • The anticipated depth of excavation is up to 20 feet.

Sources:

  • FERC (Federal Energy Regulatory Commission)
  • Xcel Energy (project submittal)
  • FERC Service (August 26, 2025)
  • Division of Dam Safety and Inspections - San Francisco Regional Office (August 26, 2025)