Dredging maintenance takes over Charleston Harbor

(Dave MacQueen/WCIV)

By Valencia

CHARLESTON, S.C. (WCIV) -- A ship sailing the Charleston Harbor may not stick out as unusual, but, the Glenn Edwards dredging vessel is worth a second look. For the first time, ABC News 4 boarded the ship responsible for keeping the harbor at 45 feet deep.

"What the dredge does is basically it has two big arms that come down and act sort of like a vacuum cleaner, and it sucks up the material off the bottom and brings it into the center part of the ship and once the ship is full, we go out to the ocean disposal site and the bottom parts of the ship will open up and dispose of that material," said Lisa Metheney, assistant chief of programs and project management.

About every 14 months, the Army Corps of Engineers does maintenance dredging on the entrance of the Charleston harbor.

"We're charged with keeping the federal channel at its authorized depth of 45 ft as much of the year as we can. So, that's why we go out and we do authorized maintenance and dredging," said Metheney. "We've been maintaining Charleston Harbor for 130 years. Not always with a nice vessel like this."

The Army Corps uses a ship called the Glenn Edwards, the largest hopper dredger in the United States.

"I've been on some other hopper dredgers and they're not quite this large. She can hold a little more than 1,300 cubic yards where a lot of other hopper dredgers can hold somewhere between{}four and six thousand cubic yards," said Metheney. "So, yeah, Glenn Edwardsshe's a big one."

With dredging, comes a host of environmental concerns.

"One of the things that we have to be careful of is the endangered turtles that are out here -- things like loggerheads," said Metheney.

Engineers also have to look out for right whales.

"Onboard this ship there are actual observers that are here during the dredging to look to make sure that we're not taking turtles and if we do happen to take a turtle they let us know. We look at the turtle and see if it's the result of the dredging operation, those types of things," Metheney said.

On average, the Army Corps of Engineers dredge 2.1 million cubic yards of sediment from the Charleston Harbor a year. Once dredged, the sediment is taken to an ocean disposal site and released.

"We also have to do regular examination of the sediment that we put out in the ocean disposal area. To make sure it's suitable for ocean disposal. We don't want to put anything into the ocean that's going to harm the fish and other types of things that we would see out there," said Metheney.

For now, Charleston's harbor is kept at 45 feet deep. But, Charleston officials want to deepen the harbor by 5 additional feet.

"With the opening of the Panama Canal, ships are going to have a bigger draft, they're going to be a little bit wider and those are the types of ships that are going to start calling on harbors. So, we need to make sure from a federal perspective, we make the harbor operate as sufficiently as possible," said Metheney.

Port officials say deepening the port would cost approximately $300 million to complete.