Closing the waterway

MOUNT PLEASANT — The Coast Guard plans to shut down a section of the Intracoastal Waterway for 10 days this month so a new swing span can be installed on the Ben Sawyer Bridge.

The Coast Guard said it will shut down the Intracoastal near the bridge at midnight Nov. 13 until 11:59 p.m. Nov. 23, for the $31.5 million rehabilitation project of the swing span. The closure will affect migratory boaters known as “snowbirds” who head south for the winter.

The contractor, PB Americas, said in a news release that the exact dates and time for closing Ben Sawyer Boulevard won’t be known until the waterway closure has begun. PB Americas plans to shut down the roadway about three days after the closure of the waterway.

The alternate route from the island to Mount Pleasant is the tall, fixed-span Isle of Palms connector.

U.S. Coast Guard Lt. Julie Miller said mariners who need to travel the waterway here are being advised to postpone their plans. She said the Coast Guard does not recommend that boaters detour from the calm waterway into the ocean. Miller said the Coast Guard has a “robust outreach campaign” to advise mariners up to New England that the waterway here will be closed temporarily beginning from 180 yards northwest of the bridge to 220 yards west of the bridge. For those who must travel here on the waterway, U.S. Coast Pilot is the best source of information on routes around the work, she said.

A modern, higher-rise fixed-span bridge would have been better than the plan to replace the Ben Sawyer Bridge with another swing span, Von Dohlen said. “I guess they think it looks better. It doesn’t make sense to me. Traffic doesn’t have to stop. You wouldn’t have to pay someone to sit up there,” he said, referring to the bridgetender’s house.

Sullivan’s Island resident Tim Holbrook said he is glad the new bridge will have the same design. “The bridge is certainly falling apart, and we’re glad to see another coming in its place. Frankly, I’m amazed that it’s going to be as little inconvenience as it is. I know it’s going to be a huge inconvenience for a lot of sailboats.”

Islanders insisted that the design of the new bridge mirror that of the existing bridge, which dates to World War II. To that end, workers will use round-headed bolts for the swing-span truss that will look riveted in place as was done when the bridge was built.

The new swing-span truss is being constructed in North Charleston at the former Charleston Naval Base. It will be brought to the construction site by barge. Massive steel girders weighing more than 10 tons each were made in Tampa, Fla., to support the bridge approaches to the swing span over the waterway.

Wooden trestles on both sides of the bridge provide a work platform and support cranes and other heavy equipment. Steel pilings driven into the pluff mud on the Charleston Harbor side of the bridge provided a temporary foundation for construction of the new approach spans. The old swing span will be rolled off its foundations onto a wooden trestle. The new swing span will be slid into place on the existing foundation, which was strengthened to better withstand an earthquake.

The current 12-foot-wide car lanes will be increased to 14 feet on the new bridge. The 2.5-foot-wide bike and pedestrian paths on both sides of the bridge will become one 5-foot-wide path on the harbor side of the bridge. The new path will be elevated 10 inches above the pavement.

Source: The Post and Courier