“We’re at the tipping point,” says Peconic Baykeeper Kevin McAllister. Indeed, considering what has happened to many of the bays of Long Island this spring and summer, we’ve tipped downward. It is imperative for public health, the environment and economy here that this be reversed. The problem in a word: nitrogen. The leading cause of changes to our bays—their turning red and brown from various forms of algae—is human waste containing nitrates moving from septic tanks and cesspools.
It began ominously in May with the waters of western Shinnecock and Quantuck Bays turning red. They had been hit with red algae—a particularly nasty strain called Alexandrium that produces a neurotoxin which can cause numbness and temporary paralysis in humans, and in rare cases can be fatal.
The red algae influx caused the New York State Department of Environmental Conservation to close this stretch of south shore bays on Long Island’s East End to shellfish harvesting and warn residents not to consume shellfish from them. It’s “a human health hazard,” explained Dr. Christopher Gobler, associate professor at Stony Brook University’s School of Marine and Atmospheric Sciences.
Earlier, waterways to the west were hit with the same red algae. Northport Bay has had to be closed to the taking of shellfish for four of the last five years as a result.
Alexandrium is a cold water species and when water temperature reaches 70 degrees it dissipates. And it did—but to be replaced in Shinnecock and Quantuck and adjacent bays with brown tide. Once sparkling, clear blue water first became red, then coffee brown.
In July, brown tide struck Great South Bay, the massive body of water between Fire Island and the south shore of the mainland of central Long Island. A few decades ago, the Great South Bay was pristine and extremely fruitful—some 60 percent of hard claims consumed in the United States came from the Great South Bay. My family spent many a glorious day out in our boat clamming in the then clear waters of Great South Bay.
Brown tide isn’t harmful to humans but it devastates shellfish and also marine vegetation by blocking sunlight. In 1985, it all but wiped out another nationally-famed Long Island shellfish, the Peconic Bay scallop. It also decimated the eel grass where scallops live and grow. Slowly, very slowly, with massive seeding of bays with scallop spawn, the Peconic Bay scallop has begun to make something of a comeback. This year there was a fairly good crop.
But it has been touch-and-go. Since 1985 brown tide returned several times to portions of the Peconic Bay system and arrived at other Suffolk bays—including, in earlier influxes, the Great South Bay.
Baykeeper McAllister speaks about septic tanks and cesspools discharging nitrates into the groundwater of Long Island—into the sole source aquifer on which all of Long Island is dependent for its drinking water. Then the nitrate-loaded groundwater moves to bays and other waterways. “The travel time is slow, a couple of feet a day. But eventually it will get there.”
McAllister is calling for the shift to “state-of-the-art denitrification systems,” advanced waste systems now available and being utilized all over the U.S. These systems, he says, should be mandated for all new construction and, when a house is sold, a “retrofit” should be required of the existing septic tank and cesspool system to a denitrification system. The Peconic Baykeeper’s analysis of the situation and plan for action is summarized in a report, “Nutrient Pollution: A Plague to Our Waters.” It’s available here.
The call of the Peconic Baykeeper must be heeded at the state, county, town and village levels.
Dr. Gobler and his colleagues have also concluded that nitrogen is the key cause of what is occurring. This past April, at a symposium on the campus of Stony Brook Southampton, they presented their extensive research. “We now know the problem and the solutions,” announced Dr. Gobler. The solutions included reducing new housing density and use of the new denitrification systems. “They’re just as effective as sewage treatment,” he emphasized.
In a recent academic paper, Dr. Gobler noted that from 1987 to 2005, levels of nitrogen in Suffolk County groundwater jumped from 40% to 200%. “These are large changes for such a brief period of time,” he wrote. And the reason: the “human population explosion” on Long Island and how peoples’ waste is disposed of.
In the wake of this summer’s influx of brown tide in the Great South Bay, Dr. Gobler said: “There are two important lessons this brown tide teaches us about Great South Bay. “Firstly, extraordinarily heavy summer rains that deliver of excessive nitrogen derived from sewage and septic tanks can have a series of serious negative impacts on the bay, including harmful brown tides. Second, the extra flushing provided by the new ocean inlet formed by Hurricane Sandy is sparing the eastern regions of Great South Bay and western Moriches Bay from the worst of this event. But clearly, this flushing is not enough to counteract the heavy loading of nitrogen from land.”
Dr. Gobler noted that since the new inlet was created on Fire Island, there has been higher salinity, lower nitrogen, stronger flushing, and less algae in eastern Great South Bay. You can learn more about the attributes of the new inlet by visiting SaveTheGreatSouthBay.org
What Long Island’s waters have been undergoing is a classic case of the admonition of the cartoon character Pogo: “We have met the enemy and he is us.”
We must move to make peace with nature for the sake of the bays and marine life and our lives. “And if we don’t wake up and restore these waters, we’re going to be hit in the pocket book,” warns Baykeeper McAllister. A Long Island of red and brown waters will be a far, far less attractive place for people to live.