February 5, 2021

Best in State: Gold award — Successful Fulfillment of Client/Owner Needs
COWI North America and HNTB

Photo courtesy of ACEC

Completing the South Lander Street grade separation remedied long-standing congestion problems in the essential east-west corridor in Seattle’s Sodo District.

Project: South Lander Street grade separation
Client: Seattle Department of Transportation

In Seattle, the busy Lander Street corridor — serving more than 13,000 vehicles, 1,400 pedestrians and 100 bicyclists daily — was frequently blocked by train traffic, causing long lines of waiting cars and trucks. Completing the South Lander Street grade separation project remedied long-standing traffic congestion problems in the essential east-west corridor in Seattle’s Sodo District.

The new bridge is better designed to handle traffic from the Port of Seattle, King County Metro, regional freight, daily commuters and visitors. It has also reduced vehicle emissions and improved freight flow, supporting economic rejuvenation for Washington state.

COWI North America worked as the prime consultant for the preliminary and final design with HNTB, who was responsible for construction management. Together, they managed the design and construction of a new bridge to span over multiple active rail lines in a dense urban area. A total of four spans supported on five piers were built over the rail lines, providing four lanes of traffic and a protected 14-foot-wide bicycle-friendly and ADA-accessible pedestrian pathway.

With an original cost estimate based on 2007 plans, the engineering team value-engineered a $20 million reduction in the overall project cost. This significant construction savings enabled the city to reallocate budgets to other city projects crucial to public safety and community development.

“This is an example of what SDOT can do, and the scale of projects we can deliver under budget, to build a safer, more livable and just city for all Seattleites,” said Sam Zimbabwe, SDOT director.

Other Stories:

• National finalist: Platinum award — Structural Systems
  Magnusson Klemencic Associates
  
• National finalist: Gold award — Water Resources
  Parsons and GeoEngineers
  
• Best in State: Gold award — Future Value to the Engineering Profession
  Century West Engineering
  
• Inclusion Award — Midsize firm
  
• Engineer of the Year
  
• Best in State: Gold award — Complexity
  Notkin, a P2S company
  
• Inclusion Award — Midsize firm
  
• National finalist: Gold award — Transportation
  HDR
  
• Best in State: Gold award — Social, Economic and Sustainable Design
  Parametrix
  
• Best in State: Gold award — Unique or Innovative Applications
  Parr Excellence
  
• National finalist: Gold award — Structural Systems
  KPFF Consulting Engineers
  
• National finalist: Gold award — Special Projects
  HDR