Their challenge

When this client needed to upgrade existing 23kV transmission lines to a 69kV system that could accommodate their customers’ growing needs, they turned to Salas O’Brien for electrical and structural engineering services. The client’s transmission lines were already built up to 69kV standards, but the conversion required an expansion to the existing station, installation of new equipment, and integration with existing rights-of-way. One of the key challenges of this design was consideration of construction sequencing. In order to safely install new equipment, construction personnel would need to maintain adequate distance and separation from live equipment, and new equipment must be ready for operation before existing live equipment could be discontinued.

Our solution

Our design solution expanded the station’s footprint so that new equipment could be constructed without premature disruption of the existing live station. Our team’s solutions also prevented multiple voltage lines from crossing by strategically relocating distribution poles and line takeoff angles to create an acceptable clearance between the lines. During the grading of the expansion area in the construction phase, our client discovered an increased slope that could cause storm water drainage onto the site. Although site preparation was not originally part of our scope of work, the client was able to leverage our civil engineers’ expertise to solve the storm water drainage issue.