MOBILE RIVER BRIDGE AND BAYWAY BRIDGE

Opportunity

In the Mobile, Alabama area, there is a need to increase the capacity of I-10 to meet existing and predicted future traffic volumes and to provide a more direct route for vehicles transporting hazardous materials, while minimizing impacts to Mobile’s maritime industry.

In 2023, AL.com reported, “It’s been another summer of backed up traffic on Interstate 10 approaching the Wallace Tunnel, and a Bayway transformed into a massive parking lot whenever a crash occurs.

“The interstate averages more than 78,000 vehicles per day west of the Wallace Tunnel in downtown Mobile, and worries continue to mount over a future in which more than 95,000 vehicles will be traveling along the interstate within 20 years.”

Solution

A new cable-stayed bridge will be constructed over the Mobile River, which will tie into the existing I-10 interstate system. Improvements will be made to the existing interchanges and new interchanges will be constructed along I-10 and US-90 in Mobile and Baldwin Counties.

The project also includes the widening of the I-10 Bayway, an 8-mile (13-kilometer) concrete structure that will be widened from four lanes to six lanes.

Outcome

Mott MacDonald was responsible for the development of 12 of the 21 planned interchange configurations and schematic designs, including improving existing interchanges and developing new interchange configurations along the I-10 corridor and US Highway systems.

Close coordination with Alabama Department of Transportation and the Federal Highway Administration was key to streamlining the environmental and preliminary design process. The project was converted to two separate progressive design-build segments, and both were underway as of summer 2023.

Mott MacDonald has transitioned to an Owner’s Design Manager role, providing plan reviews for roadway, bridge, utility, and coastal engineering for all segments.