Sounder Commuter Rail D to M Street

Making room for a greener ride

People traveling between Tacoma and South Tacoma can now do so safely and smoothly by rail. With Harris’ attention to sustainability issues, the Freighthouse Square/D Street to M street connection is also a project that environmentally conscious residents can take pride in.

Before the first shovel hit the soil, Harris performed a biddability/constructability review of the 100-percent proposed contract plans and specifications and provided more than 300 design comments for Sound Transit to review.

Throughout the course of the project, Harris provided full construction management services including:

  • Resident engineering
  • Inspection
  • Contract administration
  • Project controls
  • Scheduling
  • Estimating

In addition, Harris managed nine sub-consultants for monitoring of soils remediation, building demolition, new tracks signalization and construction materials testing, among other challenges.

Core Elements

This 1.4-mile, $41 million rail project included:

  • Lowering the roadway grade at Pacific Avenue and South Tacoma Way approximately 15 feet
  • New 50- and 110-foot spans of through-plate-girder steel bridges, supported on four- to eight-foot drilled shaft foundations
  • 10,000 feet of asphalt pavement, sidewalks, curbs and gutters
  • Major relocation of dry utilities
  • Relocating and replacing more than 10,000 feet of wet utility pipelines, including 72-inch storm and 48-inch sanitary mains
  • More than 100,000 cubic yards of earthwork
  • Demolition of nine existing buildings
  • Installation of centralized traffic control systems for rail and street signals

Beyond the Blueprints

Although the rails shine silver in the sunlight, this project is also quite green. Harris oversaw the removal of several underground fuel-storage tanks and 500,000 cubic yards of contaminated soil. We also ensured that the wetland mitigation at nearby McKinley Park proceeded according to plan.


Sound Transit


Seattle, WA


Rail + Transit


Construction Management