Transmission Line and Foundations - Maine

Jul 20

Transmission | Foundations | New England Region

Project Summary

Aldridge contributed to a major clean energy initiative, delivering up to 1,200 MW of renewable energy to the New England power grid. This extensive project spans three segments, covering over 150 miles and requiring the installation of more than 2,000 structures to support a new high-voltage direct current (HVDC) transmission line, along with key alternating current (AC) network upgrades.

Substation Foundations
Aldridge installed drilled shaft foundations for two termination stations located on either side of a major river crossing, designed to support directional drilling that routes the transmission line beneath the river. These foundations were constructed in remote and challenging terrain, leveraging specialized downhole hammers to achieve the necessary stability and precision.

AC Network Upgrades
The introduction of the HVDC line required extensive upgrades to existing AC infrastructure across multiple voltage levels. These included upgrades to 34.5kV, 115kV, and 345kV lines, along with the construction of two new 345kV sections. Coordinated across multiple segments, these upgrades were completed under stringent shutdown schedules to maintain seamless integration with the existing grid.

DC Transmission Line Installation
The DC segment consists of a 320kV HVDC line extending approximately 146 miles through varied terrain. By leveraging an existing transmission corridor for more than half its length, the project minimized environmental impacts and preserved scenic areas while maximizing efficiency and reducing costs.

Aldridge’s work on this initiative underscores our commitment to building sustainable infrastructure, managing complex project requirements, and supporting clean energy for the region’s future.