Cable Replacement – Phase 3

Project Title: Cable Replacement-Phase 3
Agency: Pacific Gas & Electric
Location: Cedar Grove, CA

Scope of work:
The scope included the installation of approximately 16,000′ of 3″ conduit appurtenant vaults, and 1 – #1/0 25kv cable through mountainous terrain at an elevation of around 7,000′, located in the Sequoia National Forest.

Challenges:
-Steep terrain, hard rock, narrow easement, dense vegetation and the presence of the exiting high voltage underground cable.
-Wildlife: numerous sighting of bears and mountain lions.
-Original plan called for generation to occur during the replacement of the old cable which would cause impact on the environment and customers.

Result/Solutions:
-During a value-engineering session, MGE came up with a solution that replaced having to run a generator while the cable was being replaced.         
     Trenching along side the existing cable resulted in:
     – Customers experiencing less service outages during construction.
     – A huge savings in project costs that could then be allocated towards other infrastructure upgrades.
     – The Forest Service was satisfied to not have a large generator running continuously for months,     
        significantly reduced the project’s environmental impact.