Underground Transmission
When you need more transmission capacity in challenging environments, we bring the experience and knowledge needed to complete your complex project or manage a massive program across multiple sites.
Underground transmission line design is a highly specialized service used to meet unique siting and capacity challenges. We are one of the few firms to offer siting and routing studies, public involvement, civil design, electrical design, construction management and construction of underground systems.
We provide innovative design-build and engineer-procure-construct (EPC) solutions to support underground transmission projects for municipal utilities, co-ops, investor-owned utilities and developers. We manage systemwide programs where we become a part of the client team, removing communication barriers and smoothing progress.
We’ve been at the forefront of this complex service, leading new developments and pioneering the installation of groundbreaking projects, such as the first and longest 500-kV underground solid di-electric transmission line in North America. We’ve chartered new territory as the engineer of record on many progressive underground transmission projects, including the first large-scale 345-kV cross-linked polyethylene (XLPE) project in the United States, and one of the longest successfully energized 345-kV XLPE systems in the country.
While we have been involved in large and complex projects, we’re equipped and connected to handle projects of all types and sizes. Whether it is an industrial application, an end-of-life asset replacement or an underground getaway out of a substation, we have done it. We help advance the development of offshore wind projects in North America and have experience applying key technologies to identify and mitigate unknown underground factors.
As the North American representative to the CIGRE cable group dedicated to establishing cable testing and commissioning standards, and as active members of the IEEE Insulated Conductors Committee (ICC) working groups, we’re not just familiar with the latest standards — we’re working to establish them. Our engineers are at the forefront of the industry and bring that unique experience and perspective directly to you.
Underground Transmission Assets
We design and build the underground transmission assets that support safe and reliable power across the grid. Among our services:
- Trenchless installation. We apply horizontal directional drilling and jack-and-bore trenchless installation experience to reduce environmental impacts, limit restoration costs and alleviate schedule impacts.
- Structure design and installation. We have experience with prefabricated and built-in-place infrastructure including ductbanks, splice vaults, cable systems and riser structures.
- Renewable interconnections. We assist with the range of steps necessary to bring renewable power to the grid, from the initial load interconnection assessment through design, installation and connection. We have in-house experience managing compliance with federal and state requirements.
- Bridge-supported cable systems. We have experience bringing disparate engineering disciplines together to successfully execute these cost- and schedule-efficient routes across water bodies or land features.
- GIS interconnections. Our team works with municipal, environmental and other interested parties to successfully install and connect urban gas insulated substations (GIS) to existing infrastructure.
- Submarine cable. Our engineering experience includes transmitting power both along inland waterways or landing it from an offshore wind farm.
