Seaweed to Trap Pollutants

Three water quality improvement projects in Springs are set to become the first to be funded by the community preservation fund, after voters last fall approved using up to 20 percent of the fund to save ground and surface water from pollution. Until now, the fund had been earmarked solely for land preservation.

A pilot program would use seaweed, or macroalgae, to trap nitrogen in Accabonac Harbor where Pussy’s Pond flows in. Very high concentrations of that nitrogen, which comes from septic waste, were found entering the harbor by surface water and submarine groundwater discharge during a recent Accabonac Harbor survey. The seaweed would be grown on frames placed in the water and would take up nitrogen; it would be periodically harvested and its growth rate and nutrient content analyzed.

The seaweed project was among a number rated by East Hampton’s water quality technical advisory committee, established to vet and make recommendations to the town board about C.P.F. water quality projects. It received a perfect score.

Also recommended during a presentation this week for the town board by Christopher Clapp, the committee chairman, was the installation of underground filtration systems, called permeable reactive barriers, at points around Hog Creek to remove nitrogen from groundwater before it flows into the creek, and replacing storm drains on Parsons Place near Ashawagh Hall and Accabonac Harbor, where existing drains that are clogged or in need of repair allow rain runoff to flow directly into the harbor.

All three projects are ready to be put out to bid, and would be the subject of public hearings once cost estimates come in.

Engineering plans and design specifications are needed to ready a number of other conceptual projects that would either treat wastewater, address pollution from stormwater or agricultural sources, restore aquatic habitats, or treat and monitor groundwater.

A request for proposals from technical consultants will be sent out so that those projects can be moved forward.

“It is worth noting,” Councilman Peter Van Scoyoc said at the board meeting on Tuesday, that a pilot project installed last year at Pussy’s Pond, where bioswales (trenches to catch, hold, and filter pollutants from water) and plantings were put in had “significantly reduced the nitrogen” in the pond.

Up to $6 million could be spent this year from the preservation fund on water quality projects, according to the present preservation fund balance, Scott Wilson, the town’s director of land acquisition, said yesterday.