FOLLY BEACH - In 2001, the Morris Island Lighthouse was leaning about 0.7 degrees to the east-northeast. The most recent measurements show that lean has grown to 1.3 degrees.
In other words, its lean has almost doubled just in the past seven years, probably mostly because of waves pounding against its aged foundation.
That might not sound like much, but it was enough to move a plumb bob suspended from the top of the lighthouse 16 inches across the floor over that time. And it was an ominous sign concerning the 158-foot-tall landmark's ability to withstand punishment from future storms.
This is why Al Hitchcock, chairman of Save the Light, is pleased that the first phase of the lighthouse-stabilization project is now complete and that work on the second phase - which will complete the foundation repair - could begin by year's end.
"I feel real good about it now," he says. "We've got the cofferdam where it will stop any large waves from pounding on the lighthouse."
The dam appears to have stopped the movement, and by year's end, the final work on the foundation could begin - work that will ensure the lighthouse remains standing for decades to come.
Before installing the cofferdam, Taylor Brothers Marine had to remove the concrete chunks left over from a foundation repair in the 1930s.
Those chunks needed to go because they would have blocked the next phase of work, which will involve jet-grouting underneath the foundation. But removing them also made the lighthouse more vulnerable than ever to the lash of the surf.
WPC Engineering provided monitoring equipment so Taylor Brothers could make sure their construction work wasn't causing the lighthouse to shift. Hitchcock says the monitors showed no ill effects from the work but definite impacts from waves.
"The wobble by the waves was probably less than 1 degree, which is not a lot. But it had been gradually doing that. It was already leaning before we started the work," he says. "The movement was caused by the water going in and out and the waves hitting the base of the lighthouse."
That stopped once the cofferdam was installed. It has sunk 30 feet under the sand and sticks about 15 feet out of the water at low tide. The interlocking, Z-shaped beams are protected by large stones on the outside so the current doesn't scour out the sand at the dam's base. And they're painted with black coal tar epoxy and have a zinc anode designed to accept all the corrosive forces so they don't hurt the metal pilings.
Jimmy Hadden of the U.S. Army Corps of Engineers says the $3.5 million job was slowed by some unforeseen obstructions but otherwise went smoothly. Taylor Brothers had to shift from working on a floating barge to a backup barge with a crane that could be jacked up on four legs. "That way he didn't have to worry about the waves beating him up while he's trying to do the work."
Hitchcock says Save the Light hopes to begin exploratory work for the next phase in a few months and begin the construction itself - which will involve jet-grouting the foundation and filling the inside of the cofferdam with sand and a concrete cap - by year's end. That's expected to cost less than $2 million, and once it's done, Save the Light can turn its attention toward repairing the lantern and other cosmetic changes.
The 3,200-ton lighthouse went dark in 1962, as the erosion on Morris Island began leaving it stranded in the sea (and as the new Charleston Light on Sullivan's Island was built).
Ever since, it has been in jeopardy of being lost.
But its future now looks bright. The Citadel has agreed to continue monitoring the lighthouse with the equipment that WPC donated, and Hitchcock says its readings soon could be posted on the Web. "The equipment is sending out a signal every day," he says.
Hadden notes the new foundation work was meant to last 50 years, adding, "Our hope and desire is that it's going to last more than 50 years."
The cofferdam around the lighthouse has allowed the removal of crumbling concrete slabs, exposing what's left of the original foundation work.×
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