High Tech Filters Being Constructed for Wares Creek Dredging

Dozens of people have been asking what is being built on the old city hall site at Manatee Ave and 15th St. West.

The parking lot has been graded flat and concrete blocks are laid out in rows as a bulldozer moves construction material, but no permanent structure is going up on the site. Instead the contractors are building a "high-tech" dewatering and processing system for the silt and water about to be thrown up on the site from the creek.

The waterproof retention and filtering system is designed to prevent materials from going back into the creek once dredging begins.

Two foot high walls are currently being put in place and will be sealed so that they are water tight. In the next few days processing machinery, including tanks and tubes will arrive on site, said Patrick Roff, Bradenton's vice mayor.

At the same time, the city is set to begin taking bids for construction of a new 9th Avenue Bridge to replace the current bridge over Wares Creek at 9th Avenue. The city hopes to begin the bridge work in April.

"It will be a traffic headache," Roff said. "But with the 30 years we’ve been waiting for this, it will be tolerable."

The bridge is being replaced to help with the creek's flow, to prevent flooding ans so that sediment does not build up once again once the creek is dredged.

Dredging is expected to begin in January. During dredging, water and silt pumped from the creek will be dumped into the tanks where the solids will be separated from the creek water. The water, which is about 90 percent of what comes up from the dredge, will be filtered through a series of tubes and cleaned before it is released back into the creek.

The solids will be separated into piles of trash, sand, clay and soil, all of which will be dried at the site. The soil will be used as covering at the Manatee County landfill, according to the dredge contract. The Department of Environmental Protection will test all of the materials and water to make sure that they are not toxic before they are removed from the site.

The water will be sent through a series of tubes where all of the sediment will be removed from the water and then the water will be filtered further and tested by DEP before it is returned to the creek.

Once the processing system is in place, dredging can begin. Roff said he expects dredging to start by the second week of January.

He said once dredging begins, crews will begin cutting mangroves for the second portion of dredging. The mangrove mass is in the creek bed and needs to be removed before dredging in that part of the creek can begin.

Roff said the mangroves will be turned to mulch and then the root system will be ripped up from the creek bed. Mangroves that are sitting on the creek bank will not be touched.

While the most asked question recently has been about the construction on the old city hall site, residents have also been curious about the Muskrat, the small dredge sitting in the urban creek. Several people have questioned the size of the boat.

But it had to be small to be able to fit under the bridges that go over the creek.They had to get something with as low a clearance as possible and even then, "They dismantled it to get it under the bridge," Roff said.

But don't let the size fool you. This dredge was made for urban projects. The end of the tube that sucks up the water and silt has a pulverizer that can chew up chunks of concrete and even bicycles.