Skip to Main Content
CDM Smith logo
CDM Smith Site Logo
Project background not configured

Practices

Transportation Design

Markets

State Department of Transportation

Priorities

Complete Corridors

Advancing NBIF connectivity through new bridges and roadway improvements 

The Cosgrove Ave. Extension bridge is a key connection serving the South Carolina State Ports Authority’s Navy Base Intermodal Facility and surrounding North Charleston neighborhoods. CDM Smith partnered with SCPA to provide planning, preliminary design, final design and construction support for the bridge as part of a larger package of roadway and bridge improvements. By carrying traffic over the facility’s new north rail lead, the bridge creates a critical grade separation while improving access to ongoing development at the former Charleston Navy Yard.

Long-term transportation planning 

CDM Smith began planning in 2009 to establish new road and rail alignments, secure right-of-way, and support development of infrastructure. 

Delivering complex bridge design solutions 

The team developed preliminary and final designs for multiple bridges, including the Cosgrove Ave. Extension bridge, providing grade separation over the new north rail lead serving the intermodal facility. 

Improving community connectivity 

Designed as a four-lane urban arterial with a shared-use path and ornamental railing, the bridge improves connectivity between North Charleston neighborhoods and emerging commercial developments. 

Supporting construction through completion 

The team continues to provide design support during construction as the bridge and roadway improvements move toward completion. 

The Cosgrove Avenue Extension project represents more than a decade of planning, design, and collaboration. After planning began in 2009, the project advanced through preliminary design in 2012 and final design in 2014 before construction started in 2023. The bridge was opened for the public in July 2026, with adjacent bridge and roadway improvements scheduled for completion by the end of the year. The project was completed by our Columbia and Charleston offices in South Carolina, with support from Charlotte, Lexington and Knoxville. Once complete, the improvements will support access to the Navy Base Intermodal Facility, which is expected to begin operations in late 2027, strengthening freight movement and economic development throughout the region. 

Practices

Transportation Design

Markets

State Department of Transportation

Priorities

Complete Corridors

Curious to learn more?

Reach out to an expert to find out how we delivered this project.

A person in a blue polo shirt standing outdoors near brick and concrete walls with trees in the background.

Stuart Healy, PE, PMP

Senior Project Manager

Stuart has experience in construction and project management for civil engineering and public works projects across roadway, infrastructure, airport, rail, water and sewer projects.

More of our complete corridors work

View All Projects
TxDOT US 67 aerial view showing highway with cars on it
El Paso District

Mixed reality fuels Texas corridor plans

View Project
Cars on I-95 in Miami approaching split for I-195 to Miami Beach with cloudy sky.
Miami, Florida

Encouraging corridor mobility on Miami’s I-95

View Project
A group of people getting on a bright light blue bus called “SunRunner” in Tampa, Florida
St. Petersburg, Florida

SunRunner: a ride the whole community owns

View Project
Glowing digital envelopes on a dark background, symbolizing email communication.

Learn more about Complete Corridors

Find out how forward-thinking communities improve mobility, promote equity and enhance resiliency through our monthly newsletter.

Sign Up
CDM Smith logo

Let’s Build Something Together

Have a project in mind or want to stay in the loop? Reach out to our team or subscribe to get the latest updates from our work.
Contact UsSubscribe

World Headquarters

75 State Street
Suite 701
Boston, MA 02109 USA
What We Do
  • Markets
  • Practices
  • Priorities
  • Projects
  • Innovation and Technologies
Who We Are
  • About Us
  • Careers
  • Cultural Threads Blog
  • Find Us
  • News
Resources
  • Insights
  • Subcontracting
  • Webinars
  • Legal & Terms of Use
  • Privacy Statement
  • Accommodation Request
  • California Privacy Rights
  • Contract Vehicles
CDM Smith™ | CDM™ | WILBUR SMITH™
© 2026 CDM Smith. All rights reserved.