Lagoon, muck projects in Dorian's sights

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(Photo: Malcolm Denemark)

Posted September 3, 2019

Chief among Hurricane Dorian's threats is the disarray and potential delays the storm could inflict on unfinished muck dredging projects aimed at restoring the Indian River Lagoon's ecological health.

Among the worries of Brevard County natural resource managers is the just-started $26.4 million dredging of Grand Canal, and what Dorian could do to the dirt berms just built off Pineda Causeway to hold future dredged up muck.

Workers on the project this week were expected to finish a four- to five- foot-high perimeter berm — made of heavily compacted soil — to keep the sediment and stormwater onsite. As long as water does not overtop berm, the structure should be able to hold stormwater in, said Walker Dawson, and engineer with Brevard County and the project manager on the dredging.

"We've got to make sure the contractor is accountable," Dawson said. "If something catastrophic happens on the site, then there's always the potential for this to be a setback."

Gator Dredging of Clearwater plans to begin Oct. 1 removing 479,000 cubic yards of muck from Grand Canal, three entrance canals and 16 residential finger canals south of Pineda Causeway. Muck is formed from rotted algae, grass clippings, and stormwater runoff containing silt and clays.

Muck is formed from rotted algae, grass clippings, and stormwater runoff containing silt and clays. When stirred up, muck stops sunlight from reaching seagrass, cutting off photosynthesis the ecologically important marine plant needs to grow. When stirred up, muck stops sunlight from reaching seagrass, cutting off photosynthesis the ecologically important marine plant needs to grow.

The dredging project will remove thousands of pounds of nitrogen and phosphorus that fuel toxic algae blooms in the Banana River Lagoon. It is the most complicated local dredging project to date in the county's $486 million Indian River Lagoon cleanup plan, officials say.

Another dredging project at a boat ramp in Mims is much further along but in a similar situation. Workers have hauled off 80% of the muck at the Mims boat ramp site but still have another 10,000 cubic yards of material to haul off to an industrial site in Mims, Dawson said.

Source: floridatoday.com