Chugach operates a substation on lots 17 and 18, Block 3, Girdwood Original Townsite. This substation has been in operation since the early 1970s. Plans for an expansion of this station in the 1990s led to the purchase of Lots 19 to 22 adjacent to, and north of the existing station. The upgrade plans were postponed, when the availability of natural gas slowed the growth of demand for electric energy in the community.
Condition and age of equipment installed in the station now make it necessary to replace the low voltage (25kV) open-air switchgear as well as the control enclosure. In order to accommodate future load growth and increase service reliability, Chugach plans to install 25kV switchgear in a metal enclosure. It will also include the controls for the high voltage (115kV) switchgear and other auxiliary equipment, such as batteries, chargers and low voltage power panels.
Load forecasts indicate that a second transformer will need to be installed between 2020 and 2025. At that time, the existing high voltage switching arrangement will not be adequate to maintain reliable service. It will be upgraded to allow termination of a looped 115kV circuit with a circuit breaker to separate line sections and taps to 2 transformers. This will occupy most of 5 (Lots 17 to 21) of the 6 lots. A wooden fence and planting of shrubs on the exposed sides of the station will enhance the appearance.
The present zoning of the additional area required for the full build out of the substation is gC-3, which allows the substation upgrade under a conditional use permit issued by the Municipality of Anchorage.
In 2009 Chugach evaluated alternative sites for a substation. In early 2010 Chugach presented the results of that study to the Girdwood Board of Supervisors. Chugach is seeking a Conditional Use Permit for the project on land it owns adjacent to the existing substation.
Schedule
| Submit Conditional Use Permit Application |
October 2010 |
| Receive Conditional Use Permit |
December 2010 |
| Procure Equipment |
2011 |
| Construct Upgrade |
2012/13 |
Proposed Development