Phalcon USA 

Northeast Utilities Southwest Transmission Upgrade

Power & Utility > Substation

The Northeast Utilities Southwest Transmission Upgrade project was divided into four segments over the course of five years. McPhee coordinated logistics for all engineered high voltage equipment and material and provided 242,976 man hours for completion of this Edison Award winning project.  


McPhee provided all logistics, coordination, and installation of engineered equipment pre-purchased by the utility of the $1.4 billion project.


As part of the first segment, McPhee provided engineer, procure, and construct (EPC) services for the new Beseck and East Devon 115/345kV substations. Our work included site preparation, foundations, landscaping, control enclosure buildings, grounding, underground conduit/cable trench, protection and control systems (P&C), steel structures, MODS, CCVTs, VTs, site lighting, AC/DC distribution systems, SCADA/RTU systems, air core reactors, overhead air insulated bus installation, 115 KV circuit and 345KV circuit breakers and generator backup power. At Norwalk, McPhee installed six new 345 KV GIS CB’s along with associated CCVT/VT/DSW/GDSW’s, LCC cabinets, P&C cabinets, cable tray, conduit, grounding, cabling, and commissioning. 


The second segment (Bethel to Norwalk) was actually completed in two phases. Work on the first phase included relocation and installation of 115KV capacitor banks, 115KV overhead transmission lines, additional bus for breaker and one half substation yard, new control system with lower level basement for cable management, manholes, duct banks, and fencing. 


During the next phase of the project, McPhee cutover the new 345kV GIS equipment at the Norwalk 9S and Plumtree Substations. The Norwalk & Plumtree substation project required demolition of the existing 115kV overhead termination structures at two bays and installation of circuit breakers, switches, 115kV XLPE underground termination structures, and drilled shaft caissons for the 345kV structures. McPhee installed the 115kV overhead to underground riser tower, the dead-end structure, riser tower structure, and the turning structure along with overhead bus, conductor and switches. 


Finally, Glenbrook Cables segment completed the renovations at Norwalk 9S substation making it the nexus of a major transmission upgrade relieving electrical transmission congestion in CT and NY. All commissioning and cutovers were performed while maintaining the integrity of the energized substation’s operation and providing electric supply to the community without interruption.