34.5kV XLPE Underground Cable Replacement

Working as an electrical contractor to Iberdrola USA, Mass. Electric Construction Co. (MEC) crews replaced three miles of electric transmission cables beneath the streets of the Old Bay neighborhood of Portland, Maine - an active area with significant business and tourist traffic.

Starting in June 2012, MEC crews completed the work plans for the removal and replacement of the underground cables, maintenance of traffic plan, and schedule for this fast-track project. By July MEC crews hit the pavement to begin the job of replacing the three (3) underground 34.5kV XLPE cable circuits.

The first circuit, Circuit 121, runs from the Union Street substation to the Cape Steam substation. A total of 5,192 feet of 500 MCM Copper EPR triplex cable was replaced through 15 manholes. A section of the submarine cable running under Portland Harbor still remains.
Circuits 122 and 123 runs in parallel and connect the Union Street substation to the Forest Avenue substation. MEC crews replaced 6,477 feet of 750 MCM Copper EPR triplex cable through 23 manholes.

MEC was also responsible for splicing, terminating, and testing all of the new cables.