King County Metro – Interim Base Electrification
LPD Engineering is providing comprehensive civil engineering services for King County Metro’s Interim Base Electrification project in Tukwila, Washington. This 12.5-acre facility will serve as Metro’s first new bus base in decades, designed to provide maintenance and charging infrastructure for 120 battery-electric buses. Our scope encompasses the detailed analysis and relocation design of critical infrastructure systems, including water, sewer, and stormwater utilities, as well as the precise coordination of underground electrical conduit alignments. A key technical challenge involves the integration of overhead charging systems supported by gantry bridges, requiring intricate coordination of 24 column foundations across multiple disciplines. The project features detailed pavement design and site grading to accommodate the specialized charging infrastructure while ensuring operational functionality. Construction commenced in 2024, with substantial completion anticipated in early 2026.
Working in close collaboration with McKinstry and Stantec through a progressive design-build delivery method, LPD Engineering’s expertise has been instrumental in developing innovative solutions for this transformative facility. Meticulous attention to civil engineering detail has been crucial, particularly in the coordination between structural, electrical, and architectural components. This $115 million facility represents a significant milestone in King County Metro’s commitment to achieving a zero-emission fleet by 2035, serving as a blueprint for future electrified bus bases while supporting improved air quality and transit equity.
