A lesson in water quality from clams
Nitrogen pollution continues to be a problem in water bodies throughout the world. Most of the nitrogen leaking into Long Island's waters comes from a surprising source.
By Nancy Kelley, Director of The Nature Conservancy's Long Island Chapter
In my 15-year career as executive director for The Nature Conservancy on Long Island, I have learned a lot from the low-lying, muck-dwelling (albeit delicious) clam.
Clams were once so abundant in Long Island’s waters it was said you could cross the 25-mile-long Great South Bay by jumping from clam boat to clam boat. In fact, in the 1970's, half the clams eaten in this country came from Great South Bay. Annual harvests four decades ago were upwards of 700,000 bushels. Now, only about 10,000 bushels are harvested annually.
© CREDIT: Kenton Rowe. Long Island’s waters create jobs and generate hundreds of millions of dollars every year for the regional economy. Local waters that are clean and healthy support tourism, boating, fishing and plentiful seafood.
The Nature Conservancy tried to improve this situation by embarking upon an ambitious shellfish restoration project that began 10 years ago. We hoped to repopulate a 21-square mile area of the bay with clams and kick-start mother nature. To date, about 8 million clams have been deposited.
Several years into the effort, though, the reintroduced clams weren’t reproducing as well as we had predicted. Some years, when we counted the numbers of live baby clams, we saw positive results. Other years, not so much. The clams were telling us something. They were telling us there was a problem with our water quality.
But what exactly was the issue? It was, and continues to be, nitrogen pollution—a problem in water bodies throughout the world that causes harmful algal blooms, kills fish, and prevents people from enjoying local beaches, bays and shellfish.
© CREDIT: Kenton Rowe. Clams are sensitive to water quality, and require clean, unpolluted water to thrive. But clams can actually improve the quality of the water if its not too degraded for them to survive.
Local research commissioned by The Nature Conservancy revealed that 65 percent of nitrogen leaking into Great South Bay comes from a surprising source: wastewater from residential home septic systems. Only 30% of Suffolk County’s 1.5 million homes are connected to sewers. The remaining 70% have outdated septic systems, sending untreated wastewater into Long Island’s groundwater and from there into its bays and harbors.
Through a major public awareness effort by the Conservancy and its partners, nitrogen pollution from sewage is now recognized as the biggest environmental threat facing Long Island. Suffolk County Executive Steve Bellone dubs it “public water enemy number one” because it threatens Long Island’s health, economy and quality of life.
In 2014, 13,000 acres of shellfishing grounds were closed because of toxic algal blooms. That number is growing. The solution lies in upgrading and modernizing our wastewater systems to reduce pollution.
© CREDIT: Kenton Rowe. The Nature Conservancy’s Long Island Chapter Director Nancy Kelley stands along the coastline at the Conservancy's Mashomack Preserve.
Getting homeowners to replace old septic systems with nitrogen reducing technology is no small feat and not inexpensive. The longer we wait to fix our water quality problem, the worse it will become and the more expensive it will be.
The good news? Long Islanders are willing to be a part of the solution. Recent polling shows that 85 percent of Long Island voters strongly support tougher water quality standards if it means that less nitrogen pollution will enter our waters, and they understand that it’s going to cost quite a few…clams.