In 2017, Hanson provided a structural assessment, data review, and utility relocation feasibility study for the City of Bellingham, Washington’s Boulevard Park pedestrian bridge project. Constructed in the mid-1970s, the bridge also carried utilities over a Burlington Northern Santa Fe (BNSF) railroad corridor. Structural deterioration caused the closing of pedestrian bridge traffic in early 2016, but the city planned to continue using it for telecom, electric, water and sewer lines until they could be relocated.

Hanson’s tasks included:

  • project management
  • coordinating with utility owners
  • assessing the bridge’s condition and recommending repairs to maintain the structure’s service life during the project
  • providing construction and local permitting support
  • assessing sewage pump capacity
  • reviewing survey, utility, geotechnical and environmental data from the nearby clean-up site to determine which data could be used and identifying data gaps to be addressed
  • preparing a feasibility study discussing utility relocation alternatives, including conceptual plans and probable construction cost estimate for each alternative

Once the city selected its preferred alternative, Hanson prepared a bid-ready plan set, specifications and an opinion of probable cost.

The selected alternative included relocating the existing sewer pump station and all utility lines from the pedestrian bridge to the city’s Bayview Drive, installing new utility casings beaneath the BNSF tracks at the Bayview Drive grade crossing and demolishing the pedestrian bridge. Hanson prepared and submitted exhibits to obtain BNSF pipeline-crossing agreements and approval of the proposed overpass demolition plan within the BNSF right-of-way. During construction, Hanson assisted the city with a submittal review and responses to requests for information.

At the completion of the utility relocation, the city expanded the project scope to include a restroom building. This portion of the work included providing:

  • site civil plans
  • utility coordination
  • drainage design, including an infiltration trench
  • environmental permitting documentation
  • specifications
  • an opinion of probable cost