The Charleston Harbor deepening project, better known as Post 45, began with a Congressional add to the President’s fiscal year 2010 budget allowing the Charleston District to complete a reconnaissance study.
The reconnaissance report demonstrated that a large percentage of the vessels currently using Charleston Harbor are tide-restricted and concluded that there was federal interest in performing a feasibility study to determine what future depth of the harbor can best reduce transportation inefficiencies and provide the most benefit to the nation. Since 2006, the average per-vessel tonnage has increased by about 25 percent for all vessels and by about 27 percent for the deepest drafting vessels. This large shift in vessel size was not anticipated in the last feasibility study (1996), which resulted in a recommendation at that time to deepen the federal channels from 40 feet to the currently authorized and maintained 45 foot depth.
In 2011, the Charleston District began the multi-year feasibility study to determine if deepening Charleston Harbor is both economically beneficial and environmentally acceptable to the nation. The study is cost-shared 50-50 between the Charleston District and the project’s sponsor, the South Carolina State Ports Authority, and conducted by the Charleston District.
Post 45 will be one of the first projects in the nation to be completed from start to finish under the U.S. Army Corps of Engineers’ streamlined civil works planning process, which aims to deliver solutions to water resources problems quicker and at lower costs.
The Charleston District has released the Final Integrated Feasibility Report and Environmental Impact Statement (FR/DEIS) for Post 45. The Final FR/EIS proposes a tentatively selected plan to deepen the major shipping channels within the harbor from 45 to 52 feet at an estimated cost of $509 million. The cost would be shared between the federal government and the South Carolina State Ports Authority at $166 million and $343 million, respectively.
The cargo transportation industry continues its shift to increased use of standardized containers used for multimodal (marine, rail, and truck) freight transportation systems. Additionally, the marine vessel fleet is trending to larger, deeper-draft vessels, particularly for containerships. The federal channels serving Charleston Harbor’s major terminals are currently authorized to a depth of 45 feet mean lower low water. The existing dimensions of those channels place constraints on deeper-drafting containerships, which result in reduced efficiency and increased costs. Benefits are generated by addressing inefficiencies in the existing transportation system to lower transportation costs. The tentatively selected plan maximizes these benefits while avoiding, minimizing, and compensating for adverse environmental impacts.
With Charleston Harbor being the fourth busiest East Coast port for container traffic with 1.5 million TEU/year, number seven of all U.S. ports for cargo value at $65 billion/year and generating more than 260,000 jobs in South Carolina, it is easy to understand why so many people have taken an interest in the future of the harbor.
The Corps has maintained Charleston Harbor for more than 140 years and has dredged it every year during that time to ensure the channel is at the required federal project depth, spending approximately $10-15 million and removing 2-3 million cubic yards of maintenance material from the harbor floor each year. Construction to deepen the harbor to the now federally authorized 45 foot depth began in 1999 and was completed in 2004.