C-HAWQ

The Coastal Habitat and Water Quality Initiative, or C-HAWQ, has been busy putting the final touches on a detailed proposal to Marco Island City Council on their novel approach to cleaning Marco’s waterways using mechanical dredging to create mangrove-covered islands throughout Marco’s canals and bays.

“Within a week or two, we should have a plan completely finalized and ready to present,” said Dan Davies, Project Executive of C-HAWQ, whose start-up funding has been supplied by EarthWerks, Davies’ Illinois-based construction company. EarthWerks offers design-build services with specialties in wetland improvement, natural infrastructure, and stormwater mitigation projects.

A seasonal resident who’s lived in Marco for decades, Davies has watched the water quality in Marco’s waterways degrade over time thanks to more than fifty years of neglect.

“The channels of Marco Island are simply stormwater utilities,” Davies said. “That’s what they were when they were originally dug and vaulted in. The second job is giving us a utility to bring our boats to the back of our houses, but none of these are natural. We created this environment that’s not natural, and like any other utility, it needs maintenance. There are no evildoers here, this is just part of our evolution in maintaining our sewers, our streets, our waters, and our stormwater utilities.”

In making his case for C-HAWQ’s approach to dredging, Davies points to a study done for the city in 2021 by Orlando-based Environmental Research and Design (ERD), indicating the need for sediment removal to improve water quality by increasing aerobic conditions but says the nearly $200 million price tag ERD cited was exorbitant.

“That’s not even in the realm of realistic,” he said. “I heard some of the details, and I said that’s not even doable. It makes no sense.”

Davies’ C-HAWQ proposal carries a price tag of $60 million, far less than the ERD proposal, and Davies says C-HAWQ would help fund the work through state and federal grants. He notes that the proposal they’ll ultimately make to the city will show their path to securing the grants required to help fund the project. “We’re not putting one dollar of the city’s money at risk,” he said. “We’ll show our avenue to funding.”

Davies’ EarthWerks has decades of mechanical dredging experience throughout the Midwest. Mechanical dredging uses excavating equipment to essentially scoop out the sediment and move it to the islands, versus hydraulic pumping to suck the sediment out and pump it elsewhere, which Davies says is far more costly and disruptive than his approach.

C-HAWQ’s proposal would use amphibious excavating equipment to dredge all of Marco’s waterways and use the dredged sediment to build strategically placed islands in waterways that are unnavigable, shallow, or in major need of water quality improvement. In other words, Davies said, all of Marco’s canals and bays would be dredged of their nearly one million cubic yards of sediment build-up, but not all waterways will have islands.

“The whole idea is to locate them strategically, either in junctions or where canals are wider,” he said. “We have to maintain navigability. Nowhere are we going to propose them where it would narrow any of the minimal channel widths.”

The islands themselves would be constructed of PVC sheet piling and rock, creating a solid receptacle of sorts for the removed sediment, anchored to the waterway floor, then topped with sand and native vegetation, including mangroves and seagrasses.

Jonathan Koepke is C-HAWQ’s environmental design lead and the owner and president of ENCAP, an Illinois-based environmental design and construction firm specializing in stream restoration, sediment control, soil erosion, and native vegetation planting and maintenance. He said C-HAWQ is working with the Naples Botanical Garden to develop their mangrove propagation and planting plan. 

“In five to ten years, these islands will look very similar to the natural mangrove islands you see all around Marco,” he said. “These will be permanent structures. The last thing to be wiped out in a hurricane will be these islands.”

Koepke said that while there are similar dredging projects that proved successful in coastal areas such as Savannah and the Chesapeake Bay, C-HAWQ’s approach brings a level of innovation exceeding prior projects.

“While all of these construction methods are proven individually, this is the first time anyone has proposed to combine them in the way C-HAWQ proposes,” he said. “That’s the uniqueness of this proposal. That’s the innovation that our project team brings to this opportunity.”

For his part, Davies says cleaning Marco’s waterways with C-HAWQ’s novel approach will be replicable in other similar coastal towns in Florida and beyond.

“Marco’s water systems are officially designated impaired,” he said. “I am confident with every ounce of reputation I have that within the next five years, you’re going to have a fishery on the island again.”