Transforming the beach

Army Corps’ heavy machinery is reshaping the shoreline

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History is in the making as the beach landscape in Long Beach is transformed by the Army Corps of Engineers’ $230 million coastal protection project, which is intended to defend the city against future storms like Hurricane Sandy.

“It’s historic,” said City Council President Anthony Eramo. “It’s the first time we’ve had any sort of engineering of our beach, and you can see what a huge difference it makes. The beach is practically doubled in size, and sand quality is fantastic. I’m very proud to be part of the City Council that voted to finally protect our island . . .”

The work, which has included constructing jetties, replenishing sand and building protective dunes, is progressing quickly, thanks to some very heavy machinery.

A 35-foot-tall, three-legged machine that can be seen traversing the sand, called the CRAB, or Coastal Research Amphibious Buggy, plays an integral role in the sand-replenishment process, the second phase of the project, which is currently taking place.

The project’s contractor, Great Lakes Dredge and Dock Corporation, uses the CRAB to survey the underwater slope of the beach, explained Army Corps Project Manager Dan Falt.

“They run the crab prior to beach-fill to see what the slope of the shoreline is, and then they’ll use the CRAB again afterwards to see how much sand they put in, and if they filled the template correctly,” Falt said. “You could go out there with a stick and divers, and swim and measure it, but that’s pretty difficult, and that takes a lot of time, and there’s waves, so they actually use that device that’s fairly unique — there’s not many of them around — to measure the beach.”

After the CRAB measures the sand, a dredge boat connected to a pipe sucks up sand and pumps it onto the beach. About 4 million cubic yards of sand will have been hydraulically pumped onto the beach by the time the project is completed, which is expected to be in the winter.

Dredge Boat Illinois, the Coast Guard-inspected dredge used by Great Lakes, is a cutter suction dredge described as a “floating platform equipped with a rotating cutter that excavates the sea floor by feeding the loosened material into a pipe and pump system that typically transports the material and water slurry up to five miles away from the site.”

It’s like a drill bit and a vacuum, Falt said, that cuts into the sand in the “borrow site” — the area about half a mile offshore from which the sand is extracted. The machine digs a hole and slurps up the sand, along with seawater. The slurry is then pumped through a 30-inch pipe along the sea floor and sent to the beach.

“At that point, they start attaching sections of pipe one after the other as they fill in portions of the beach,” Falt said. “When the sand gets pumped out of the pipe, the sand just drops and the water runs back into the ocean.”

A thousand feet of beach at a time is closed off to allow for the sand placement, which will extend the beach 200 to 300 feet between the water and the new dunes. The work is currently taking place between Roosevelt and Lincoln boulevards, moving west, Falt said.

Once the sand is pumped onto the beach, bulldozers smooth it out and fit the beach profile into the template designed by the Army Corps. Then the CRAB comes back, along with other surveying tools, to measure the beach and make sure it complies with the plans.

“It’s a simple process, but it’s not easy,” Falt said.

The work often catches the attention of passersby on the boardwalk, who are intrigued by the process.

The project “is a wonderful thing — it gives us protection from future storms, and we gained beach,” said Bill Tansey, president of the West End Civic Association. “These people are moving at breakneck speed, and they’re doing a great job. I think it’s worth every penny that the government is spending on it.”

“As an engineer, I’ve been fascinated by the Army Corps project,” City Councilman John Bendo said. “It’s not only the precision of their work, but the speed at which they’re moving. They’re moving massive amounts of sand and significantly increasing the sizes of our beaches, especially where our beaches were narrow, like in the West End. And even with all the choreography of the bulldozers, barges and ships moving miles of pipes and tons of sand and water, they’re moving along the beach at a rate of several hundred feet a day.”

“I’ve also been surprised at how fast the beaches have been reopened,” Bendo said. “The improvement to our beaches, and, more importantly, the enhanced protection we have on the ocean side should another storm come, make whatever temporary inconvenience this project may have caused worthwhile.”