Firm Makes Fresh Tracks Through South Florida Muck

Thu November 11, 2004 - Southeast Edition
Giles Lambertson

A 50-year-old marina in Naples, FL, is being recycled into a brand new condominium-hotel-yachting complex on Naples Bay. One of the first steps in the redevelopment process is deepening the basin around which the complex will be built.

The site is one of three parcels of land totaling 43 acres (17 ha) that are being redeveloped by Antaramian Development into what will be named Naples Bay Resort. The resort’s marina section alone will have 98 slips, an 85-unit hotel, 30 waterfront condominiums, a private yacht club and plenty of commercial space.

Gulf Shore Site Development Inc. was given the interesting task of tearing down old Boat Haven Marina docks that lined the basin, emptying out bay water from the marina inlet and then digging away several feet of the exposed basin floor. It is a $1.5 million job.

Gulf Shore contracted to accomplish all of that while working within tolerances acceptable to hovering environmental agencies and inspectors of the U.S. Corps of Engineers.

Notwithstanding the challenges, said Jim Raiser, chief estimator and treasurer of the family-owned development firm, “it’s gone pretty much as planned.”

He gives that assessment on a late October day, four months after demolition of the old dock areas began and a few weeks after the last of three hurricanes blew through Naples.

Much of the company’s demolition of docks, covered boat slips and storage areas that comprised the old marina was done from the deck of a 190-foot (57-meter) long barge. Case and Link-Belt excavators with thumb attachments at the working end of the excavators’ extended arms were positioned on the barge to take apart the aging structures.

Demolition took about two months.

The next challenge was to get to the floor of the basin to deepen it. The strategy settled upon was to drain one half of the basin at a time.

“An earthen dam was one of our options,” Raiser said. However, the environmental engineering firm overseeing the project, Turrell and Associates, frowned on the idea of sediment from the dam fouling the bay waters. “So that was ruled out.”

Raiser and three brothers — Richard, Mac and Tom — who comprise Gulf Shore leadership, found a damming solution on the Internet: the Portadam Inc. system of diversion and cofferdam structures.

The system uses fabric membranes laid across the face of steel frames that slope backward at about 45-degree angles. Water pressure on the membrane-covered frame tends to transfer pressure downward, anchoring the structures.

Gulf Shore lined up the 10-ft. (2.7 m) tall sections in the marina basin, essentially cutting it in half as the dam stretched across the inlet about 140 ft. (43 m). A 24-in. (60-cm) hydraulic pump then was dropped into the area that was to be evacuated. MWI Corp. supplied the pumps.

Pumping the water directly over the top of the Portadam structure into the bay proper was not allowed by Turrell or the Corps. Sediment is necessarily sucked up with the water in such an operation and emitted as a bubbling, muddy discharge. Environmental engineers do not approve of such emissions.

The bay is coming back from decades of environmental neglect. Besides being degraded by properties adjacent to the bay, it also has been affected by fertilizers and other chemicals carried to it by rivers running from the everglades that occupy the center of southern Florida not far inland from Naples.

To protect the bay water, additional Portadam sections and fabric were used to construct a temporary tank on shore. Its dimensions are about 175 ft. (52 m) by 60 ft. (18 m) and it holds nearly 1 million gallons (3.8 million L).

The evacuated water is pumped into the holding tank. The impounded water subsequently passes through a filtering system and then is discharged into the bay. Engineers each hour sample the water drawn from the tank to make sure the water is adequately filtered.

The process eventually was repeated for the other half of the basin, which was drained after erection of a second Portadam nearer the mouth of the inlet. The structure was about 160 ft. (48 m) long.

The first phase of the task, damming, exposed the bottom of the basin for the second phase, removal of material. To no one’s surprise, the surface of the bottom was muck. Mud, silt and decomposing organic matter was up to 3 ft. (.9 m) deep in places.

Decades of silting had rendered the waterway pretty shallow. The goal of the project is to put the bottom of the basin fully 6 ft. (1.8 m) below sea level so that larger, deeper-drafted boats can ply the waters above it.

With a 12-in. (30 cm) hydraulic pump pumping to stay ahead of seepage around and under the temporary dam, Gulf Shore began to “de-muck” the basin. The muck was pushed to the edge of the basin by John Deere 650 and New Holland dozers. There, excavators loaded it into Terex off-road trucks. The sloppy material was trucked to the far side of the property where it was dumped for drying and eventual re-use as fill dirt.

Equipment operating in and near the basin is required by the environmental engineers on site to be “oil-free,” meaning that grease leaks and oil spurts that are acceptable on most projects are unacceptable here. Equipment is inspected regularly, Raiser said.

The trucks and some other pieces of heavy equipment on the project were rented from ASAP Rental Equipment and Sales, and Nations Rent, two local equipment suppliers.

How much muck was moved? Raiser estimates that more than 3,000 cu. yds. (2,280 cu m) of it was trucked away.

Any treasure chests found in it? Raiser laughed off the suggestion.

“We did find some interesting bottles dating back 50 years,” he said. “Lots of whiskey bottles, of course, but some original Mountain Dew and Coke bottles, too.”

Hurricanes Charley, Frances and Ivan interrupted this de-mucking process. In each case, the project was shut down temporarily and water pumped back into the emptied area to stabilize the Portadam against storm-churned waves.

“We were concerned that the storm water would go over the top of the dam,” Raiser said of the precautionary pumping. The dam held in each storm — Ivan never really reached the area — though the Gulf Shore crew had to retie the fabric to frames where hurricane winds had blown them loose.

Three or four days were lost to each storm, but Raiser reports that down time was the only loss.

Cleared of muck, the first section of the basin’s coral floor was ready for ripping apart. For a couple of reasons, the removal of rock is a more complicated process than it might have been.

The Corps of Engineers told Gulf Shore that it shouldn’t just hammer the rock apart because that process was too imprecise. If more rock were removed that way than the 2 ft. (60 cm) permitted for removal, the contractor would have to fill it back in.

“Permitting is always an issue,” Raiser said of the various hoops that contractors must jump through in environmentally sensitive situations.

Nevertheless, he added that on this project, Corps engineers “have been very cooperative.”

The other reason jarring apart the rock was considered an unacceptable risk is the condominiums that will be built right up to the seawall. Kelly Brothers Marine Contractors has the contract to erect those sea wall panels.

The developer was concerned that shattering the stone in the basin bottom with hammers might lead to inadvertent fracturing of adjacent rock beneath the foundation areas of the condos. Any such fracturing could destabilize the structures.

For these reasons, Gulf Shore turned to Hydro Rock Co. Inc. of Fort Myers.

The company will strip away 2 ft. (60 cm) of the coral floor using a massive open-wheeled milling machine.

Weighing 90 tons, the machine will rip down to the final grade sought by the engineers. Each pass of the milling machine will lay open a 14-ft. (420-cm) wide swath of crumpled rock, moving ahead about 50 ft. (16 m) each hour of operation. The loose rock left behind will be scooped up by front-end loaders and trucked a short distance for eventual use as rip-rap and fill rock.

Several weeks will be devoted to the milling. As of late October, the rock work hadn’t begun, but the machine was on site and had been tested.

“This is the first time anyone in Naples has tried anything like this,” Raiser said.

Because the process of milling is especially noisy, the work day on the site has pretty much stayed in the 7 a.m.-to-5 p.m. realm out of respect to neighbors.

Antaramian Development project manager John Khozozian agrees that the marina renovation is “going pretty much as planned” despite the incursion of hurricanes Charley, Frances and Ivan.

Once the deeper basin is a fact and the Portadams removed, another contract will be awarded to cut a new channel out into the bay from basin areas. Gulf Shore Development will bid for that contract, too, Raiser said.

The channel widening will be a joint venture by several adjacent property owners, the deeper channels inviting deeper-pocketed owners of yachts to the marina properties.