Charleston Harbor is now 52 feet deep, the deepest harbor on the East Coast, the South Carolina State Ports Authority said Monday as state and federal leaders gathered to mark the end of a project that took more than a decade.

The roughly $580 million job lets the biggest ships calling on the East Coast reach the authority’s terminals at any time and any tide, according to the authority, known as SC Ports. The harbor was 45 feet deep before the work, The Post and Courier reported.

“It is a truly historical moment to be celebrating this monumental achievement. Charleston Harbor has been deepened to 52 feet,” SC Ports President and CEO Barbara Melvin said to cheers, according to the authority. “With the deepest harbor on the East Coast, we can efficiently work mega container ships at any tide.”

U.S. Sens. Lindsey Graham and Tim Scott, Gov. Henry McMaster, U.S. Rep. Nancy Mace and officers of the Army Corps of Engineers joined port officials at the event in Mount Pleasant, according to SC Ports and The Post and Courier.

How deep, and where

The Army Corps of Engineers’ Charleston District and SC Ports partnered on the project, according to the authority.

The entrance channel was deepened to 54 feet. The harbor now has 52 feet of water up to both Wando Welch Terminal in Mount Pleasant and Leatherman Terminal in North Charleston, and 48 feet between Leatherman Terminal and North Charleston Terminal, SC Ports said. Turning basins in front of Wando Welch and Leatherman were widened so ships can pass one another and turn around without restrictions.

At 52 feet, ships carrying 16,000 or more 20-foot containers can call on the port regardless of the tide, and the waterway is wide enough for two of the supersized vessels to pass side by side, The Post and Courier reported.

The port tested the new depth in September, when the MSC Rayshmi arrived with a port record draft of 48 feet, 11 inches, according to the newspaper.

Who paid

The project was paid for with state and federal money, SC Ports said. The General Assembly set aside $300 million in 2012, the full estimated cost of the state’s share, The Post and Courier reported. In 2019, Congress appropriated $138 million, funding the project to completion, according to the authority.

“That bold move made this infrastructure possible,” Melvin said of the state’s early commitment, according to The Post and Courier. “It showed the federal government we weren’t playing around.”

Dredging began in 2018. The Army Corps awarded five dredging contracts, three to Great Lakes Dredge and Dock Corp., one to Norfolk Dredging Co. and one to Marinex Construction Inc., and the work took four years, SC Ports said.

The project started with a feasibility study in 2011 and was the first to go through a new Army Corps planning process meant to cut time and cost, The Post and Courier reported. It finished two years ahead of schedule, and enough material was dredged from the harbor floor to fill 12,000 Olympic-size swimming pools, the newspaper reported.

‘Close to failing’

Graham told the crowd the project nearly died more than once.

“We came close to failing three times,” he said, according to The Post and Courier.

The project got an early lift in January 2012, when then-Charleston Mayor Joe Riley pitched it to President Barack Obama during a brief handshake in Washington and Obama added it to his “We Can’t Wait” initiatives, The Post and Courier reported. Graham said that when money for a key study was later stripped from the federal budget, he told then-Senate Majority Leader Harry Reid he would hold up nominations until it was restored. In 2019, he said, the Trump administration put $138 million in the budget, and that “closed the deal.”

“South Carolina can now proudly say that we have the deepest harbor on the East Coast,” McMaster said in a statement released by SC Ports. “The 52-foot depth gives South Carolina a major edge in recruiting new jobs and investment while announcing to the world that this is the place to do business.”

Lt. Col. Andrew Johannes, commander of the Army Corps’ Charleston District, said the harbor averaged only 12 feet deep in 1760. It was first deepened, to 17 feet, in 1851, he said. This project was the eighth deepening of the harbor, according to The Post and Courier.

What it costs to keep

The work is not over. The Army Corps will perform maintenance dredging on the project’s three sections on different cycles, at an estimated cost of $35 million in fiscal 2023, The Post and Courier reported. The agency said the cost will likely be higher in fiscal 2024, the first year all three sections will need maintenance, according to the newspaper.

Melvin said the depth will help the port compete for more ships and cargo.

“This depth makes us more competitive. This depth attracts more investment and business to our state,” she said, according to The Post and Courier.