Peninsula study benefit-cost-ratio increases to 11.3, as USACE adjusts plan to reduce risk on Port properties, prepares final report

U.S. Army Corps of Engineers, Charleston District
Published Jan. 25, 2022
Updated: Jan. 25, 2022

As part of its ongoing optimization and in light of public and agency input on the Charleston Peninsula Coastal Storm Risk Management Study, the U.S. Army Corps of Engineers (USACE), Charleston District continues to adjust the proposed plan by further increasing project benefits, decreasing cost or reducing environmental impact.

Among the adjustments to the plan since the study’s release of the draft Feasibility Report and Environmental Impact Statement (FR/EIS) in September 2021 is the recent realignment of the storm surge wall along the South Carolina Port Authority’s downtown property.

These continued refinements have improved the proposed plan’s benefit-cost ratio from 10.2 to approximately 11.3, increasing the project’s net benefits and the measure used to evaluate federal investment.  The realignment of the wall along the South Carolina Port Authority property also brings with it a reduction in visual impact by moving the wall further away from historic structures and onto an active port terminal.

Over the next few months, the study team will continue to refine the proposed plan, using public and agency input, to produce the study’s final FR/EIS. The final report will reflect all adjustments to the proposed plan and include responses to public and agency comments submitted during the study’s formal comment period. The final report will be published in late spring 2022 on the study’s website.

Later this year, the final FR/EIS will be submitted to the USACE headquarters office for potential signature by the USACE Chief of Engineers. The City of Charleston’s active support and willingness to complete the feasibility study continues to be an important part of the process for the USACE Chief of Engineers to make a determination whether to approve and sign the report. If signed, the Chief’s Report would be submitted for potential congressional authorization and funding which would enable USACE to move to the next phase, Pre-Construction, Engineering and Design (PED).

Providing the assurances necessary for completion of the feasibility phase will not legally obligate the City of Charleston to enter into the PED phase or a subsequent construction phase. For each of these potential, subsequent phases, the City will need to enter into a separate agreement with USACE to carry out the phase. However, the PED process will enable the City and USACE to develop a fuller picture of the recommended plan which will enable the public to better understand the specifics of what is being recommended before proceeding to any construction.

PED will provide the opportunity for the study team to collaborate with the City of Charleston, stakeholders, agencies and the public in further refining project alignment; address project design (including visual aspects of the wall); explore prospects for additional natural and nature-based features; and consider other refinements. PED cost-share amounts would be jointly determined by the study team and the City of Charleston and would be based on annual funding requirements.

For more on the realignment and the study’s next steps, view the Preview of the Recommended Plan published on the study website at


Jackie Pennoyer
(843) 329-3378

Release no. 22-001