ECI was contracted by Southeastern Electric Cooperative to provide engineering and construction services for the EPC Buffalo to Capitol 115 kV Project. This 115 kV single circuit transmission line began at the newly expanded Buffalo Substation located in northwest South Dakota and extended west, terminating into the new Capitol Substation in the southeast corner of Montana. ECI performed a complete substation and transmission line design package with the transmission line complying with RUS design standards.

The transmission line is approximately 31 miles long and was constructed primarily using RUS TH-1AAX-type tangent h-frame, TH-3AA-type running angle, and TH-5AD-type dead-end structures. Conductor for this line was designed as single-conductor 336 ACSR “Linnet” with 7 strand 3/8” EHS shield wire located in both static positions. As part of the overall planning and engineering, ECI’s planning and GIS team also completed several feasible route studies including development of maps showing various landowner and/or environmentally sensitive areas. These studies allowed ECI to coordinate with landowners and other government entities to determine the best, most comprehensive, and cost-effective route.

ECI, through its subsidiary EPC Services Company, provided Materials Procurement as well as Safety Assurance, Construction, and Materials Management for the project. In addition, ECI’s host of responsibilities included management of the right-of-way acquisition along the 31-mile corridor, survey, and overall project management including cash flows, scheduling, and ongoing project reporting.