The Massachusetts Estuary Project, which studied 12 Island bodies of water, has raised awareness of growing nitrogen problems and spurred action at several levels.
Man-made breaches at Island ponds help maintain salinity for shellfish and eelgrass and flush out nitrogen that accumulates mostly from septic tanks and runoff.
Without wastewater treatment facilities, Island ponds could be in worse shape. Estuaries suffer from nitrogen overload, coming mostly from septic systems that remove bacteria but not nitrogen.
A few hundred alternative systems are installed on Martha's Vineyard, mostly in Edgartown and Oak Bluffs. The technology could help achieve nitrogen mitigation in Island coastal ponds.
All the saltwater ponds on the Vineyard are impaired to some degree, and each one faces a unique set of conditions. Public interest has reached a tipping point.
Sengekontacket Pond has been closed to shellfishing because of rainfall received earlier this week.
The town of Oak Bluffs has advised that the pond will be closed until at least Monday, August 17.
The state mandates pond closures after heavy rainfall because of run-off from waterfowl and other sources. Red flags fly at both bridges on the pond when it is closed to shellfishing.
While the Vineyard is perhaps best known for the ocean, Vineyarders have deep ties to the ponds that were carved into the Island landscape some 20,000 years ago.
Island ponds are a connection to cultural heritage and a livelihood for fishermen. But housing booms and land-use changes threaten to undo a delicate balance.
