Section 106 Consultation for the Tiger Creek 201 Undergrounding Project

Strategic Insights -

The Pacific Gas and Electric Company (PG&E) has proposed to underground 4.34 miles of electric distribution facilities on the Tiger Creek 201 CB12 12 kV Line in Amador County, California, as part of the Mokelumne Hydroelectric System. The Federal Energy Regulatory Commission (FERC) requires consultation with the State Historic Preservation Officer (SHPO) to ensure compliance with the National Historic Preservation Act of 1966. PG&E has defined the Area of Potential Effects (APE) as approximately 69 acres and has identified eight cultural resources within the APE, including the Tiger Creek Hydroelectric Subsystem Historic District and Tiger Creek Powerhouse and Switchyard.

Key Takeaways:

  • PG&E proposes to underground 4.34 miles of electric distribution facilities on the Tiger Creek 201 CB12 12 kV Line.
  • The project will consist of underground conduit for electric distribution lines, associated utility boxes, transformers, riser poles, and protection features for above-ground facilities.
  • Eight cultural resources were identified within the APE, including the Tiger Creek Hydroelectric Subsystem Historic District and Tiger Creek Powerhouse and Switchyard.
  • PG&E applied the criteria of adverse effects pursuant to 36 CFR § 800.5(a) and determined that the undertaking would not cause adverse effects to historic properties.
  • The SHPO agrees that the APE is appropriately defined, but recommends further efforts to identify historic properties and potential for discovering undocumented historic properties.
  • The SHPO withholds comment on the proposed finding of effect and pauses the consultation until additional information is provided.

Statistics:

  • Approximately 69 acres have been defined as the Area of Potential Effects (APE).
  • Eight cultural resources were identified within the APE, including the Tiger Creek Hydroelectric Subsystem Historic District and Tiger Creek Powerhouse and Switchyard.
  • PG&E proposes to use a combination of trenching and boring within the right-of-way with standard trench depths at least 30 inches below ground and maximum depths of approximately 110 inches below ground.
  • The project will remove above-ground overhead electric distribution facilities, including poles, conductor, and anchors.
  • The SHPO recommends that PG&E seek information from consulting parties likely to have knowledge of or concerns with effects to historic properties, including state recognized and federally recognized Indian Tribes.

Sources:

  • California State Historic Preservation Office: Department of Parks and Recreation, Office of Historic Preservation
  • Pacific Gas and Electric Company: Arran Bell, Senior Cultural Resource Specialist
  • Federal Energy Regulatory Commission: FERC_2025_0813_001