News Summary
The Mark Clark Extension road project, a long-debated infrastructure initiative, has been terminated after a unanimous vote by South Carolina’s Transportation Infrastructure Bank. The project, which aimed to extend Interstate 526 across Johns and James Islands, faced overwhelming opposition, culminating in a failed referendum. With significant funding already spent and traffic concerns remaining, local officials are exploring alternative solutions to manage congestion as planning shifts focus to other road improvement projects in the area.
Charleston, SC – The long-controversial Mark Clark Extension road project has been officially terminated as of May 12, 2025. The South Carolina Transportation Infrastructure Bank’s board, in a unanimous vote, ended its contract with both Charleston County and the South Carolina Department of Transportation, bringing to a close decades of planning and extensive opposition from the community.
The Mark Clark Extension was intended to extend Interstate 526 across Johns and James Islands, projecting a total cost exceeding $2.3 billion. However, the initiative faced significant hurdles, including a failed half-percent sales tax referendum in November 2024 that saw over 61% of voters reject the funding necessary to support the project. Only 11 out of 182 voting precincts in Charleston County showed support for the referendum.
Before the project’s termination, Charleston County had invested approximately $8.4 million into the development, with several million expected to be recouped. Interestingly, only $75 million of the funds specifically allocated to advance the project was ever utilized. The state Department of Transportation will retain control of properties along the intended route, which cost $41 million to acquire. This includes a vacant property on James Island purchased for $1.7 million in 2015, which remains unoccupied.
As the cancellation of the Mark Clark Extension leaves traffic concerns unmet, primarily due to the growing population on Johns Island—approximately 25,000 residents, up from 15,000 in 2010—local officials are now seeking alternative traffic relief strategies. Road improvement plans are already in motion for Johns Island, focusing on Maybank Highway and Main Road, with a significant $354 million construction project set to remodel the U.S. Highway 17 and Main Road interchange slated for 2025.
The board’s decision to terminate the Mark Clark Extension project signals not only the end of a long-fought battle but also indicates a need for transparency in future infrastructure projects. Local council members have emphasized the importance of rebuilding public trust following the failure of the referendum and have indicated that future meetings will address negotiating terms with state partners to find a resolution regarding the future of the Mark Clark Expressway.
The infrastructure bank had initially contributed $420 million to the Mark Clark Extension, but as expenses ballooned over time, this figure has significantly dwindled relative to overall costs. To date, just under $58 million has been spent, primarily on land acquisitions, before final plans were abandoned.
The termination of the Mark Clark Extension project is a pivotal moment for Charleston County residents, prompting immediate discussions about alternative solutions for traffic management and community development. Local leaders will continue to seek strategies that balance the needs of the growing population while addressing the challenges posed by ongoing transportation issues.
Deeper Dive: News & Info About This Topic
HERE Resources
Charleston Launches New Sustainability Initiative: The Just Corridor
Taryn Barbot Wins CAA Player of the Year Award
Additional Resources
- ABC News 4: State Transportation Infrastructure Bank Ends Mark Clark Extension Project Funding
- Wikipedia: Infrastructure
- Post and Courier: Mark Clark Extension Update
- Google Search: Mark Clark Extension Charleston County
- Live 5 News: County Leaders Discuss Next Steps on Mark Clark Expressway
- Google Scholar: Mark Clark Extension Project Charleston
- Charleston City Paper: County Advances Tax Referendum for Mark Clark Extension
- Encyclopedia Britannica: Transportation Infrastructure
- Post and Courier: Charleston Mark Clark Extension Tax Funding
- Google News: Charleston County Traffic Solutions
Author: STAFF HERE CHARLESTON
The CHARLESTON STAFF WRITER represents the experienced team at HEREcharleston.com, your go-to source for actionable local news and information in Charleston, Charleston County, and beyond. Specializing in "news you can use," we cover essential topics like product reviews for personal and business needs, local business directories, politics, real estate trends, neighborhood insights, and state news affecting the area—with deep expertise drawn from years of dedicated reporting and strong community input, including local press releases and business updates. We deliver top reporting on high-value events such as the Spoleto Festival USA, Charleston Wine + Food Festival, and the MOJA Festival. Our coverage extends to key organizations like the Charleston Metro Chamber of Commerce and the Charleston Museum, plus leading businesses in tourism and maritime industries that power the local economy such as South Carolina Ports Authority and the Charleston Visitor Center. As part of the broader HERE network, including HEREaiken.com, HEREbeaufort.com, HEREchapin.com, HEREcharleston.com, HEREclinton.com, HEREcolumbia.com, HEREgeorgetown.com, HEREgreenwood.com, HEREgreenville.com, HEREhiltonhead.com, HEREirmo.com, HEREmyrtlebeach.com, HEREnewberry.com, HERErockhill.com, HEREspartanburg.com, HEREaustin.com, HEREcollegestation.com, HEREdallas.com, HEREhouston.com, and HEREsanantonio.com, we provide comprehensive, credible insights into South Carolina's dynamic landscape.
