SWAN LAKE HYDRO FACILITY

OWN, OPERATE & MAINTAIN

SEAPA owns 2 Hydroelectric Projects

This includes the Swan Lake Hydro Facility which is dedicated to Ketchikan Public Utilities and Tyee Lake which is dedicated to Wrangell Municipal Light & Power and Petersburg Municipal Power & Light

SWAN LAKE HYDROELECTRIC FACILITY

The Swan Lake Hydroelectric Facility is located on Revillagigedo Island at the head of Carroll Inlet, about 22 miles northeast of the City of Ketchikan.

PRIMARY FACILITIES INCLUDE:

  • reservoir with a surface of 1,500 acres at normal maximum elevation and usable storage capacity of 86,000 acre-feet between elevations 330’ and 271.5’
  • 174’ high concrete thin arch dam (430’ long at its crest)
  • controlled ogee spillway section, 100' long with flashboards and a vertical spillway gate, effectively raising controlled spill elevation an additional 12' from elevation 330' to elevation 342’
  • 2,217’ long, 11’ diameter power tunnel
  • powerhouse with two Francis turbine generating units having an installed capacity of 25 megawatts (MW)
  • 13.8/115-kV substation located adjacent to the powerhouse
  • port facilities 1000’ north of the powerhouse, a staging area adjacent to the port facilities, and access roads from the port facilities to the powerhouse and dam
  • 115 kV transmission line extending from the powerhouse substation 30.5 miles to the existing S.W. Bailey Substation

PLANNING, OPERATIONS & MAINTENANCE INCLUDE:

  • Power scheduling
  • Interaction and coordination between communities and utilities to deliver bundled energy and power
  • Annual inspection of the entire STI
  • Outage response
  • Project and records management
  • Plan, coordinate, and oversee major maintenance of facilities and infrastructure
  • Plan, coordinate, and manage key projects known as Renewal and Replacements (R&R) that ensure long-term reliability and availability of hydropower across SEAPA’s interconnected system

Near the end of project construction, the State of Alaska, under the department of the Alaska Energy Authority, assumed ownership of the project from Ketchikan and began commercial operation in June 1984. Ownership transferred from the State to the Four Dam Pool Power Agency (FDPPA) in 2002, and when the Agency restructured in 2009, the FDPPA’s name was formally changed to the Southeast Alaska Power Agency.

Copyright 2022. SEAPA Hydro | All Rights Reserved