Duff-Coleman 345kV Transmission Line Transmission

Client Republic Transmission, LLC (LS Power)
Completion Date 2020
Location Indiana
Completed by MYR Energy Services, Inc. and The L.E. Myers Co.

MYR Energy and L.E. Myers partnered for the engineer-procure-construct (EPC) delivery of this 33-mile 345kV single-circuit transmission line from the Duff Substation in southern Indiana to Coleman Station in northern Kentucky.  

As the prime contractor, MYR Energy oversaw procurement and construction, which L.E. Myers managed. The scope of work included Stormwater Pollution Prevention Plans (SWPPP) and environmental installation, right-of-way (ROW) access, foundations, pole setting, and all line work. WPPP, access, and foundations and drilling were subcontracted.  

This project expanse used two wire bundle 1590 conductor with two optical ground wires (OPGW) and features structures that are primarily steel direct embed H-frames with three-pole direct embeds for running angles and dead ends. The project included one drilled pier foundation crossing near Tell City, Indiana. 

The extra-high-voltage transmission line was developed to increase reliability by strengthening the region’s transmission backbone and reduce congestion, allowing lower cost generation resources to reach load. The result? Safe, reliable power delivery and lower system costs for the entire MISO electric transmission grid.  

It was the first project in the Midcontinent Independent System Operator’s (MISO) footprint eligible for competition under Federal Energy Regulatory Commission (FERC) Order 1000.