By John Pacenti
For months, Manalapan commissioners sought to determine whether or not Palm Beach County’s sand transfer plant at the Boynton Inlet was to blame for erosion of its shores.
An engineer and beach erosion expert hired by the town to look at its erosion issue says the transfer plant — which pumps sand south to Ocean Ridge and beyond — is not the big, bad bogeyman after all.
The culprits are old-fashioned sea walls, lack of a comprehensive dune policy and Mother Nature, particularly tropical storms like 2012’s Hurricane Sandy from which the town’s beaches never truly recovered.
The conclusion is no surprise, but still grim: Manalapan faces critical erosion challenges, especially on the town’s north end, where one-time residents Billy Joel and Yanni could dig their toes into the sand.
Where a luscious beach once stood outside of the Vanderbilt estate, now at high tide the sea wall often juts into the ocean.
It appears residents will have to decide — more likely sooner than later — if they want to truck in expensive sand to replenish their beaches.
“Your primary issue that you should focus on is ‘how do we get enough sand, how do we maintain the sand location’ and not try to correlate that too closely with what residents — individual residents — have done,” said Doug Mann, lead coastal engineer with APTIM.
He gave an hour-plus presentation, including a question-and-answer session, at the July 8 Town Commission meeting.
Mann’s comprehensive knowledge of all things beach and erosion in Palm Beach County was on full display. He said there was actually a bit of a benefit from the sand transfer plant on the south end of Manalapan, but that any “accretion” is not present north of the Chillingworth Curve at 1500 S. Ocean Blvd.
“One day, the plant runs, and you move some sand off the beach, and it gets bypassed. The next day, there’s not enough energy or enough sand there to bypass. So the county turns the plant off, and the beach starts to accrete again,” Mann said. “So you have both of these processes going on at the same time.”
The study revealed significant beach narrowing over the decades. “The beach is lower and it’s not as wide as it used to be,” Mann said, showing photos of changes since 2001.
The northern portion of Manalapan’s beach appears the most vulnerable, eroding “pretty substantially” over the last 30 years, Mann said.
Existing sea walls complicate the situation. While doing a bang-up job of protecting multimillion-dollar properties, Mann said sea walls “cause a redistribution of sand” that may “push some sand directly offshore, particularly when you have a severe storm.”
Sea walls have been rebuilt along the former Vanderbilt estate after failing during storm surge from Hurricane Sandy. Yet, Mann showed a picture with a sea wall jutting into the ocean where the beach was nonexistent.
While there had been some dune renourishment in the 2000s by a homeowner, the town has never adopted a dune master plan or renourishment policy, Mann said.
The town in May disbanded its beach committee after it found beach erosion, the sand transfer plant, and beach raking to be areas of concern. Now the matter is in APTIM’s hands.
The Manalapan report shows the extent of erosion in the 1300 block of Ocean Boulevard. There is no berm, a mild sloping beach to the sea wall and no dune plants.
The initial study, presented July 8, cost $10,000, with additional APTIM work in a second phase to cost taxpayers between $17,000 and $20,000.
“We’re going to complete the analysis of some coastal data,” Mann said. “Look at what beach nourishment may look like in town. We’re going to look at whether the selective use of some coastal structures in combination with future dune nourishment may be appropriate.”
Potential solutions include “groins, breakwaters, or a combination of both” to maintain the shoreline. However, Mann warned that any intervention must consider environmental factors like near-shore hard bottom — where corals grow — and nesting sea turtles.
Public funding remains a significant hurdle. “Your beach is fairly private, with limited public access,” Mann said, meaning the project “would have to be funded by the town itself and its residents.”
The U.S. Army Corps of Engineers “will only work on beaches that are public and open to the public,” he said.
Commissioner David Knobel highlighted the urgency, stating the town needs “to slow the decline of this beach and have a long-term plan, whether it’s publicly or privately funded.”
“Get dunes back there, get groins if it’s needed,” he said.
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