Cables strain, engines hum and gears turn as leverman Thomas Gillikin carefully positions the spiral-tipped cutterhead 24 feet below the waters of Port Royal Sound for another pass.
He flips a switch, hits a button and gently pushes a lever. He surveys the bright computer monitors that surround him, feeding data on the volume, velocity and viscosity of the sand and saltwater slurry being ground by the cutterhead, then sucked out and pumped by the floating dredge. He has to be careful to avoid clogging the pipe or overexerting the equipment, which could lead to costly delays.
Gillikin is in the driver's seat of a project costing more than $10 million that will pump about 1.1 million cubic yards of sand from offshore onto a one-mile stretch of beach between the Westin Resort & Spa and the Beach House in Port Royal Plantation.
He and other crew members have been working 12-hour shifts since just before Christmas to help the Town of Hilton Head Island combat a decade of erosion that has claimed about 80 to 100 feet of beachfront a year. Left unchecked, the erosion could threaten oceanfront property, town officials say.
Great Lakes Dredge and Dock Co. has been pumping an average of 35,000 to 40,000 cubic yards of sand each day nonstop -- more than double the average for previous town renourishment projects.
"The weather window has been superb," said Scott Liggett, town director of public projects and facilities. "They started before Christmas and have stayed out there continuously with no significant mechanical delays, with plenty of opportunity for things to go wrong with so many moving parts."
About 200,000 cubic yards remain to be placed on the beach, which should be done next week, Liggett said.
Crews are also building a 700-foot-long wall made of granite boulders to stabilize the beach. The $1.6 million structure will trap sand that normally would be lost to coastal drift, but it will also allow some sand to move over its top so as not to deprive other beach areas.
Work should be completed by May, Liggett said.
Town Councilman Bill Harkins was amazed during a tour Thursday at the size and complexity of the project.
"It's like a floating factory out here," Harkins said. "It's definitely a very high-tech operation. ... And the result is our island, which is known for its fantastic beaches, can be preserved for years and years to come."
Follow reporter Tom Barton at twitter.com/EyeOnHiltonHead.
- Crews lay pipe, ready for beach fill and groin at island's eroding heel: Dec. 17, 2011
- High tides and winds erode Hilton Head beaches: Nov. 1, 2011
- Island council awards contract for Port Royal beach renourishment, OKs borrowing: Aug. 2, 2011
- On Hilton Head's heel, sand continues to be lost to nature, permit delays: April 16, 2011