Thursday, March 28, 2024 Blog · News

Submit comments: The harm of the I-526 Extension

by Emmi Palenbaum

The S.C. Department of Transportation has submitted an application to fill in over 38 acres of wetlands to construct the I-526/Mark Clark Extension. You can find the full application here. 

This is a greater wetland impact than was predicted in previous environmental assessments for the project, and it comes before Charleston County residents have had the opportunity to vote on whether they will approve a new sales tax to fund the $2.3 billion project. 

Take a look at the proposed route below. The construction impacts are far-reaching, and would be felt heavily throughout communities around the Charleston area for years to come. Although SCDOT has not shared a predicted completion date, we know that a best case scenario takes this project into the next decade, with significant reverberating effects well beyond that.  


Proposed route for I-526 Extension / S.C. Department of Transportation


Please take a few moments to email comments on this application to T. Brian Hardee with the U.S. Army Corps of Engineers by April 9.  


The costs and harmful impacts of this outdated highway project seem to grow by the month. And the fact that this permit application was submitted before Charleston County voters have a chance to cast their vote in November suggests that decision-makers don’t really care whether residents support this overpriced, irresponsible project—even though they’re asking residents to pay the bill! 

Fortunately, you have a chance to weigh-in on the permit application. Submit comments to the U.S. Army Corps of Engineers and the S.C. Department of Health and Environmental Control to share your concern with filling over 38 acres of wetlands to build a 9.5 mile road that will destroy wetlands, disrupt communities, and lead to more development on rural Johns Island. 

See below for points to consider when drafting your comments, and instructions for how to submit. Please make sure to personalize your comments and request public hearings! 

Please feel free to reach out with any questions or ideas. You can email Robby Maynor or give him a call at (843) 723-5127. 



Talking Points for Public Comments 

I-526/Mark Clark Extension Permit Application 

Comment Deadline: Tuesday, April 9, 2024 

Email Comments to: T. Brian Hardee, Project Manager  [email protected] 

Subject Line: Public Comments for I-526/Mark Clark Extension Permit SAC-2010-00642 


Major Points to Include: 

1. Destruction of wetlands and other important waterways 

The proposed 526 Extension would cut through marine ecosystems and freshwater wetlands that are integral to water quality in the already-impaired Stono River. The proposed route would destroy over 38 acres of wetlands and other waters of the United States, including freshwater, wetlands, ponds, and tidal salt marshes. 

Wetlands provide important ecosystem services to nearby communities through flood storage and wave buffering; that role has become increasingly valuable in light of the region’s recent exposure to storm hazards, which is only projected to worsen due to climate change. Wetlands also provide wildlife habitat, fish nurseries, water purification, erosion control, food supply, and carbon storage. 


2. It won’t shorten your commute 

Charleston County’s claims that the 526 Extension will reduce congestion and enhance mobility are based on faulty traffic predictions and ignore cheaper, more effective alternatives to reduce congestion and increase mobility. 


3. Susceptibility to future flooding 

The proposed 526 Extension crosses a low-lying coastal ecosystem. Portions of the project close to sea-level could be exposed to several feet of water with even a low-level hurricane. Within the next decade, we could also see effects from tidal flooding in certain areas.  


4. Restriction of access to existing natural and recreational spaces 

The proposed 526 Extension will destroy 32 acres of James Island County Park, which includes a climbing wall, bouldering wall, challenge and ropes course, park headquarters building, public access to a creek, over three acres of park wetlands, habitat for plants and wildlife, and parts of the disc golf course, campground and associated cottages. 


5. Extending brings more development pressures 

The Mark Clark Extension will induce additional suburban development in rural areas of Johns Island which will make traffic congestion worse and lead to additional impacts to wetlands and other critical natural resources. We saw this happen dramatically in Mount Pleasant when 526 was extended across the Cooper River in 1992. 


6. Displacement and disturbance of community health and well-being 

The 526 Extension will disproportionately impact environmental justice communities. The proposed route bisects or borders seven census blocks with disproportionately low-wealth or minority residents. Residents along the route will either be forced out of their homes or subjected to significant and harmful air, water, and noise pollution. 


7. Potential for an unfinished mess 

Breaking the 526 Extension into two distinct phases introduces news risks that only portions of the project would be completed. This would have significant impacts on the overall purpose and need of the entire project and could have wide-ranging negative impacts that have not been thoroughly evaluated. 


Request a Public Hearing: Make sure to include a specific request for the U.S. Army Corps of Engineers and the S.C. Department of Health and Environmental Control to host public hearings in communities directly impacted by the 526 Extension 

 Reasons for public hearings include: 

  • Hosting an in-person public hearing is more equitable, since not everyone has reliable access to the resources necessary to submit comments independently. 
  • This is a massive infrastructure project that will impact multiple communities, including West Ashley, Johns Island, and James Island. For a project of this size and scope, it is imperative that the public is adequately informed and has ample opportunity to share their thoughts and concerns. 
  • 38.5 acres of wetland impacts is very large and impactful, much larger than average permit applications–even for other road/infrastructure projects. For example, the Main Road Flyover (Main Road Segment A) at the intersection of Main Road and Savannah Highway would impact less than 10 acres of wetlands. 







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