Town Receives $1 Million Grant For Miacomet Pond Dredging

Nantucket has been awarded a $1 million grant from the Inland Dredging Pilot Round, part of the Massachusetts Dredging Program managed by the Massachusetts State Executive Office of Economic Development (EOED).

This funding will support the dredging of Miacomet Pond to enhance water quality and recreational opportunities. The total project cost is estimated to exceed $4 million to remove as much as 100,000 cubic yards of material from the 46-acre pond.

The Natural Resources Department and Nantucket Land Bank, in collaboration with Geosyntec and the Horsley Witten Group, are currently in the planning and permitting stages of the dredging project. A notice of intent application is currently pending before the Nantucket Conservation Commission. This effort aims to significantly improve the ecological health and recreational value of Miacomet Pond.

Jeff Carlson, the town of Nantucket’s Natural Resources Department director, can talk about the science behind dredging material to improve the health of the pond. But the analogy he used to break it down in layman’s terms seemed to hit the mark for those of us not trained in biology.

“It’s like playing Nintendo in the old days,” Carlson said. “You’d get mad and hit the reset button and start over.”

The dredging project could represent a reset for Miacomet Pond by removing a thick benthic layer full of nitrogen and phosphorus from years of fertilizer use and septic systems around the pond. The accumulating muck has leached those nutrients back into the water, Carlson said, fueling the harmful algal blooms and invasive species that have plagued Miacomet Pond.

“By removing the benthic layer that causes the nutrients to recycle into the pond, you’re removing that source front the pond itself and kind of resetting the pond to some degree,” Carlson said.

The possibility of dredging Miacomet Pond to remove existing nutrients in the sediment had been proposed as long ago as 2005 when it was among the conclusions of a study of the pond by then-town biologist Keith Conant.

The first-of-its-kind project for the island would be a sort of proof-of-concept effort to demonstrate that dredging can, in fact, improve the health of Miacomet Pond, and perhaps be a water quality solution for Nantucket’s larger ponds.

The grant received by the town this week was part of a highly competitive cycle, with a total of $4 million available statewide and $14 million in grant requests submitted. 

At about one mile long, Miacomet Pond has a maximum depth of 11 feet near its southern end and the mean depth of the pond is 4.8 feet, according to town records. The pond is where approximately 1,284 acres of the surrounding landscape drains into, so it has numerous sources of nutrients that have had harmful effects.

Carlson added that dredging the pond would also represent an alternative to using an alum (aluminum sulfate) treatment for nutrient binding, another way communities sometimes deal with excessive nitrogen and phosphorus.