2023 ENR Northwest Best Projects
Excellence in Sustainability, Award of Merit - Airport-Transit: Trimet Powell Garage
Photo by Josh Partee
TriMet Powell Garage
Portland, Ore.
Best Project - Excellence in Sustainability, Award of Merit - Airport/Transit
Submitted by: JE Dunn Construction
Owner: TriMet
Lead Design Firm: Stantec
General Contractor: JE Dunn Construction
Civil/Structural Engineer: DEA
Mechanical/Plumbing Engineer/Fire Protection: Glumac
Electrical Engineer: Reyes Engineering
Landscape Architect: Marianne Zarkin Landscape Architects
Equipment: HDR Maintenance Design Group
First built as a temporary facility more than 45 years ago, the TriMet Powell Garage was overdue for a modernization to improve safety, capacity and employee well-being. Creating a new sustainable and modern hub for the city of Portland’s public transit system required a phased rebuild across a 17-acre site.
Scope included demolition and replacement of nearly all existing facilities. Thanks to early planning and constant communication between the team and owner, the transit hub also remained fully operational throughout construction. Jersey barricades, fencing, traffic control signage and daily coordination kept construction areas separate from TriMet’s active operations.
Photo by Josh Partee
Powell Garage’s design prioritizes daylight and views, acoustics, thermal comfort and indoor air quality for all staff. Catwalks and pathways around the exterior edges of the building provide safe indoor and outdoor paths around the campus, separating bus and pedestrian traffic.
Completed on budget and ahead of schedule in November 2022, this project will serve as a role model for future facilities. Phase 1 included a 24,000-sq-ft fuel and wash building, while Phase 2 more than doubled the original bus maintenance area. Powell Garage now houses 22 maintenance bays and a 400,000-sq-ft concrete-paved bus yard that can accommodate more than 300 buses. A second story provides more office space, a new fitness center, training rooms, roof-top patio and spacious break area.
Photo by Josh Partee
During the bid packaging process, the contractor placed heavy focus on creating packages well-suited to minority and disadvantaged business enterprises. This effort resulted in a more than 26% Certification Office for Business Inclusion and Diversity (COBID) firm participation rate.
During construction, TriMet asked JE Dunn to install infrastructure to support its goal of having a 100% zero-emission fleet by 2040. This included electrical service enhancements for charging in the bus storage area and additional charging stations inside the maintenance facility. Crews also built a 10,000-sq-ft vehicle repair basement that provides access to the underside of buses from lifts below, eliminating tight working spaces and reliance on bus lifts.
Photo by Josh Partee
The project team embraced a holistic approach to sustainability. Passive design strategies included shading large glazing expanses and cutting down energy consumption, heating and cooling loads and maintenance. A water reclamation system housed in the fuel and wash building recycles up to 300 gallons of water per minute during the bus wash cycle. Sloping roof planes collect and store rainfall in rooftop cisterns as a supplemental source for hot water heating, while the site’s design allows for 100% onsite stormwater infiltration.
