Dredging Begins In Martha’s Vineyard’s Chilmark Pond

Dredging in Chilmark Pond’s Lower Basin advances a long-planned effort to improve the pond’s health and resilience. Photo/Chilmark Pond Foundation

Environmental groups have been advocating to have Chilmark Pond on Martha’s Vineyard dredged for more than five years. Last month, that dredging finally began.

Photo/Chilmark Pond Foundation

The Chilmark Pond Foundation — an environmental group that works to restore the pond’s ecological health and preserve it for future generations — announced dredging began in the Chilmark Lower Pond in early November. Officials with the foundation said the dredging and beach nourishment work is a big step toward restoring the long-term health and resilience of Chilmark Pond.

Monitoring over the past several years has shown that an accumulation of sand has resulted in shorter cut duration, reduced water exchange, and limited flushing capacity.

Photo/Chilmark Pond Foundation

These impacts were evident in a recent Chilmark Pond cut on March 2, 2025, which lasted only four days. The pond was opened again on April 24. Foundation officials said this was a good opening with considerable tidal exchange before the pond closed on May 5.

Officials said the lack of a cut results in reduced flushing of the pond with clean (salty, clear, low-nutrient) seawater, increased nutrient (nitrogen and phosphorus) build-up, and continued ecological stress.

Over time, sand builds up in the pond as the result of the ocean’s action moving sand with the tides and closing the breach. This causes more sand coming into the pond than being pushed out, shallowing the pond and creating a delta near the opening that restricts the flow of water in and out of the pond, reducing the flushing capacity of each pond opening or “cut”, making them shorter and less beneficial to the pond’s ecological health.

The current dredging project is designed to create two channels near the cut, removing sand buildup, which will allow cuts to better drain the pond and promote healthy tidal exchange of pond and ocean water.

The dredging project will dig up 6,000 cubic yards of sand from the pond.