SeaTac Concourse Low Voltage Upgrade

The Concourse Low Voltage project at Sea-Tac International Airport aims to modernize the electrical infrastructure at one of the nation's busiest airports, specifically focusing on Concourses B, C, and D. This initiative involves replacing outdated systems to ensure all electrical components meet current codes and can support the airport’s evolving operational needs. This project is more than just a simple cable upgrade; it represents a strategic investment in the airport's long-term resilience and capacity.

Renovating an active, aging facility like Sea-Tac presents unique challenges. Decades of previous construction and modifications have created a complicated network of electrical systems. To tackle this, Mortenson’s team conducted thorough investigations of existing conditions, with electricians carefully tracing each conduit and circuit panel by panel. This detailed assessment was crucial for understanding the current infrastructure and informing the design of the new system.

Executing the project requires careful planning and coordination. Mortenson has scheduled approximately 200 electrical shutdowns, each lasting between one and four days. These shutdowns are strategically planned to occur between midnight and 4 a.m., minimizing inconvenience to airport operations. Coordination with tenants and staff is a top priority to ensure that all stakeholders are informed and prepared for each phase of work.

A key aspect of the project is the consolidation and removal of unused infrastructure. By eliminating obsolete systems, our team is creating space for future airport expansions and reducing congestion in back-of-house areas. The upgrades also include the installation of code-compliant panels and increased electrical capacity in Concourse D, directly supporting anticipated growth and operational demands.

With completion targeted for mid-2026, the Concourse Low Voltage project provides Sea-Tac Airport with a modern, reliable, and scalable electrical backbone. Mortenson is proud to partner with the Port of Seattle on this vital upgrade, ensuring the airport is well-prepared to serve travelers and tenants for decades to come.