As reported from the Bay County Public Information Office:
Crews will begin removing the boom in the St. Andrew Pass on Wednesday morning, after state Department of Environmental Protection Agency officials determined the state would fund the effort.
“The chance of any surface oil making it here is almost zero,” Bay County Emergency Services Chief Mark Bowen said, highlighting that the purpose of the boom was always to fend off surface oil threatening the bay — it would have been ineffective against subsurface oil or tarballs. “Surface oil arriving here would be unthinkable at this point. The imposition of the pass project to shipping traffic and recreational boaters far outweighs the minimal risk of any surface oil.”
First to go will be the rigid high-density polyethylene (HDPE) boom pipe chained to the 54 pilings standing in the pass, according to Bay County Public Works Director Ken Schnell. He said the boom on the Shell Island side of the pass will be removed first. The stretch of boom on the west side of the pass will be removed next, followed by the areas that comprise the project’s gate.
Crews will then work to remove the sheet pilings on each side of the project and continue to work from the outside in toward the middle of the pass removing the free-standing and dolphin pilings that remain.
At no point will the pass be closed to boat traffic, though boaters should exercise caution in the area of the construction and maintain a no-wake zone, Schnell said. The 65-foot safety zone on either side of the pilings remains in effect.
The project is expected to take as many as 45 days, weather permitting.
“They could do it in as quick as 30,” Schnell said.
DEP is footing the bill for the project’s removal, at a cost of about $437,000, which is considerably lower than initial estimates in the neighborhood of $1 million.
“We made that estimate before we drove the first piling,” Schnell said. He said that because the contractor will be able to salvage the materials once the removal is completed helped lower the cost.
The pilings, he said, will be removed using a vibratory hammers and a barge crane, which will essentially wriggle them out of place. The pilings are buried by half their length below the bay floor, with those in the deepest part of the channel underground by some 50 feet.
Bay County received a $3.1 million BP payment for the project’s construction on July 22.
The boom system is comprised of 18 42-inch free-standing steel pilings and another eight pile “dolphins” (each consisting of three pilings attached together with a cap on them) that were driven in the center of the pass. The total of 54 pilings vary in length depending on the depth of the water, and extend at least 10 feet above the mean high tide level. About half their entire length is buried below the bay’s floor. The boom is made of 30-inch diameter, two-inch thick HDPE pipe and has a 48-inch long HDPE fabric weighted skirt hanging below the pipe, with a 400-foot HDPE boom pipe gate located in the center of the waterway.