From Pittsburgh to Las Vegas, electric companies are taking their transmission lines underground … and GAI is helping to make their efforts a reality.

In 2005, under contract with Underground Systems, Inc. (USi), GAI provided civil design, surveying and drafting services for Duquesne Light’s Arsenal-Highland upgrade project in Pittsburgh, Pennsylvania. Key to the project was building new underground transmission lines between Arsenal and Highland substations in Pittsburgh’s historic East Liberty neighborhood, for which GAI played a major role in the surveys, design and construction plans.

In 2007, USi again contracted GAI for civil design, surveying and drafting services on two major underground transmission line projects. One project involves relocating a substation in Louisville, Kentucky and another involves building a new substation in Las Vegas, Nevada. Aesthetic reasons often play a big role in a utilities decision to go underground. Overhead lines obscure the impact of historic city scenery, such as in Pittsburgh and Louisville. Or, in the case of Las Vegas casinos, the dramatic city scapes and bright lights.

In the Louisville project, GAI is assisting in the design of rerouting underground cables and is working with local authorities regarding the underground utilities along the proposed corridor. GAI engineers are researching the geology and performing critical borings in order to develop a plan for the new routing. The project also involves developing construction specifications and design drawings for the project.

The Las Vegas project is larger in scope than both the Pittsburgh and Louisville efforts. Prime contractor Sargent & Lundy LLC is designing Nevada Power Company’s new Collman Substation, an effort that will support the growth of the Las Vegas Resort Corridor and help meet future projected electrical and system reliability demands in the Las Vegas valley. The new gas-insulated 138/12-kV substation will be located within a decorative wall adjacent to Echelon Place, a new casino resort complex under development.  Five miles of new 138-kV transmission line, with provisions for a future 230-kV circuit, will connect Collman Substation to Highland Substation to the north and Decatur Substation to the southwest. USi and GAI have been contracted to design up to five miles of underground transmission line as part of this project.

“Partnering with USi on these underground transmission line efforts has been extremely rewarding for the GAI transmission line team,” says GAI Director of Transmission Line and Structural Engineering Steven S. Miller. “We look forward to a lot of growth in this area in the next few years and are excited about the prospects of more underground transmission line projects in the future.”