The most extensive capital program in the Maine Turnpike Authority’s history, the Portland Area Widening and Safety Improvement Program has transformed safety, mobility and the region’s opportunity for economic development.

As long-time partner and general engineering consultant to the Turnpike, HNTB played a key role in the planning, design and delivery of the complex program, which includes:

  • 5 centerline miles of widening, drainage, median barrier and safety improvements
  • 16 bridges modified
  • 4 interchange modifications
  • 1 interchange reconstruction
  • 1 toll plaza replacement
  • 4 large culvert extensions
  • 2 new emergency vehicle ramps

Careful Planning Keeps Traffic Rolling

At the height of the program, there were three to six active construction projects happening concurrently, all with interdependent work scopes and outcomes. However, the interrelationship of these contracts meant that, if one fell behind, the entire program would be impacted.

Recognizing this, and in response to the Turnpike Authority’s desire to minimize construction impacts on traffic operations, the HNTB team spent considerable time analyzing options for sequencing and phasing the work with the goal of maximizing efficiency and safety, while also minimizing risk. The result was a detailed and time-bound contracting and sequencing plan for the program that outlined the limits and scope of construction for nearly a dozen separate contracts with a clear understanding of the relationship between each contracts respective schedule, work zone, traffic control signage and construction access.

The team’s approach resulted in a comprehensive and well-reasoned approach to construction sequencing and traffic management that thoughtfully balanced contractor needs, safety and mobility. Because free flow conditions were maintained at almost all times during construction, the delay experienced by motorists was minor.

Support for the Turnpike and the Region

Supporting the Turnpike every step of the way, HNTB has helped deliver infrastructure improvements expected to serve the growing Portland area for the next 20 years.

Location: Maine

Client: Maine Turnpike Authority

Services: General engineering consultant, planning, design, construction support services

Awards: 2024 Honor Award, ACEC Maine; Top 10 Roads List #1, Roads and Bridges Magazine

Read More: Widespread Benefits, Designer article