Project Overview

Project Purpose

The purpose of the Mark Clark Extension project is to increase the capacity of the regional transportation system, improve safety, and enhance mobility to and from the West Ashley, Johns Island and James Island areas of the Charleston metropolitan area.

Project Development Process

The Mark Clark Extension project will continue to follow the standard project development process for large-scale roadway projects. In 2019, Charleston County, South Carolina Department of Transportation (SCDOT), and Federal Highway Administration (FHWA) re-initiated the efforts to complete the National Environmental Policy Act (NEPA) review process.

Understanding the Project Development Process

The project development process normally begins with early efforts to identify the need and purpose of a project. However, early scoping for the Draft Environmental Impact Statement (DEIS) (2010) established the purpose and need for the project along with the development of the various conceptual alternatives. These alternatives were presented to the public for their input. The Mark Clark Extension begins with FHWA and SCDOT determining that a Supplemental Environmental Impact Statement (SEIS) is required to include the collection of current data and the re-evaluation of all the alternatives.

SEIS and FEIS and Permitting

During the National Environmental Policy Act (NEPA) review process and as part of the 2021 SEIS efforts, the project team will re-analyze the 39 alternatives from the 2010 DEIS, including updates to data to reflect changes that have occurred in the project study area.

Public involvement has been an integral part of the development of alternatives for the Mark Clark Extension project and will continue through the Public Hearing and the completion of the project. A Public Hearing was held from August 18, 2021 through October 15, 2021, and the materials identifying the recommended preferred alternative are available on the Public Hearing page. The 2021 SEIS is located on the documents page.

During the completion of the Final Environmental Impact Statement (FEIS) and Record of Decision (ROD), strategies and mitigation efforts will be identified to minimize the project’s impacts on the community and natural environment. Once the ROD is signed, and necessary permits are obtained, the project enters the final steps before the beginning of construction. These include the identification, negotiation, and purchasing of the necessary right of way. Since the project is anticipated to be delivered as a Design-Build project, design and construction may begin and overlap the right-of-way phase.

Environmental Review Process (NEPA)

The Federal Highway Administration (FHWA) National Environmental Policy Act (NEPA) process allows transportation officials to make project decisions that balance engineering and transportation needs with social, economic, and natural environmental factors. During the process, a wide range of partners, including the public, businesses, interest groups, and agencies at all levels of government, provide input into the project and environmental decisions.

NEPA requires Federal agencies to prepare an Environmental Impact Statement (EIS) for major Federal actions that significantly affect the quality of the human environment. An EIS is a full disclosure document that details the process through which a project is developed, the consideration of a range of reasonable alternatives, the potential impacts of the alternatives, and compliance with applicable environmental laws.

An EIS document consists of:

• A description of the project;

• The purpose and need for the project;

• An analysis of possible alternatives for the project;

• Studies of the existing human and natural environment;

• A summary of potential effects on the environment that each alternative may have; and,

• Identification of a Preferred Alternative by SCDOT.