US Route 4 over Bunker Creek, Durham, NH - Design-Build

Client: NHDOT

Construction Cost: $5 Million

Key Facts:

  • Public Outreach & Stakeholder Coordinate
  • Complex NEPA Documentation
  • Alternative Development & Analysis
  • Hydraulic & Hydrologic Analysis
  • Structural and Highway Engineering
  • Utility Coordination
  • Design-Build Procurement

GM2 provided comprehensive engineering and environmental services for the preliminary engineering phase of this complex reconstruction project within an environmentally sensitive region. The scope of work included alternative development, roadside design, hydraulic and hydrologic analyses of the tidal controlled Bunker Creek, public information meetings and coordination, drainage design, and bridge design. Environmental tasks included wetland delineation and permitting, NEPA documentation, endangered species review, and shoreland permitting.

The project involved widening US Route 4 to accommodate bicycles and improve drainage and existing roadway geometric deficiencies. The profile was raised to meet the required design speed and increase the sight distance to meet the AASHTO requirements. GM2 served as the owner’s representative through the design-build procurement process, working collaboratively with NHDOT on the delivery of the replacement of the bridge and roadway improvements. These services included Request for Qualifications and Request for Proposal document preparation, review of design-build team proposals for compliance, Alternative Technical Concept review, and final design plan review.