Posted on December 1, 2025
After years of delays, the Chilmark Pond Foundation is finally dredging Chilmark Lower Pond this month in an attempt to improve the pond’s water quality.
The nonprofit got the go ahead earlier this year to dig up 6,000 cubic yards of sand from the pond, and Chicago-based contractor ILM Environments started dredging at the start of November. The hope is that taking out the sand from the pond will result in better flushing out of the water when the pond is opened up to the ocean.
Chilmark Pond has been struggling with its water quality for years and cyanobacteria blooms are now a regular occurrence in the summer, threatening the life and enjoyment of the coastal pond along the town’s south shore. Sand has accumulated into the pond, making full flushes difficult when the nonprofit cuts the pond annually. Dredging will be a critical piece to help when the nonprofit creates an opening in the pond to the Atlantic, said Amy Salzman, an ex-officio member of the pond foundation.
“What you really like in an opening is to have the pond pretty much drain out into the ocean and then refill with ocean water, and then drain and refill,” she said.
This creates an exchange of biological organisms in the pond, lowers the pond’s temperature and steadies the balance of ocean and pond water.
“We were just not getting really healthy exchange of ocean and pond water [right now],” Ms. Salzman said. “The hope is that we will start seeing longer openings with these monitors that tell exactly how deep the pond is, what the temperature is, what the salinity is, so we will, I think, be able to see whether this was worth all the work.”
The permitting process for getting a dredge has been long and arduous. The foundation first filed applications in 2020, and found itself bounced around to various agencies as environmental regulations kept changing.
In 2023, the permit was in its final stages before plans were momentarily halted due to the potential for harm to the endangered northeastern beach tiger beetle in the area where the sand is planned to be put along the barrier beach.
“[The U.S. Fish and Wildlife Service] would spend some time trying to come up with some scientific protocols for us to be able to survey and see whether there were beetles there, and if so, where they were, and if so, whether they would be harmed by our activity,” Ms. Salzman said.
The federal government deployed scientists to work with Island-based BiodiversityWorks to develop the protocol last year. Then, the foundation was granted the permit in March from the U.S Fish and Wildlife Service.
The first phase of the dredging will be finished by the end of the year, according to Ms. Salzman, and it is part of a multi-pronged approach to build pond resilience.
This past summer, the foundation put an ultrasonic buoy into the pond to shoot out waves that disrupt the forming of cyanobacteria.
Ms. Salzman is also looking into thin-layer placement, a process where nitrogen- and phosphorus-rich mud is removed from the bottom of the pond and distributed along the shoreline, building up marshes and increasing pond resiliency. While it has not been done in Massachusetts yet, the state has shown interest in developing a pilot program.
Ms. Salzman is thankful for the support of the community with continuing preservation efforts, and sees them potentially as a model for other towns.
“This really is a community project,” she said. “It is privately funded by the people around Chilmark who care about Chilmark Pond, and we hope, frankly, that it will become a model for other restoration efforts on the Island and elsewhere.”
