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Posted 07.30.07 $617M Later, no clear picture of Sound's health The Stamford Advocate By Tim Stelloh Twenty years ago, Long Island Sound was practically dead. An abundance of nitrogen - largely from sewage treatment plants - had fueled the growth of oxygen-depriving algae suffocating shellfish and fin fish across broad swaths of the Sound. By 1994, New York, Connecticut and the federal government came up with a plan to restore the Sound's health. At the top of its list was solving the nitrogen problem. A few years later, officials set a timeline: By 2014, the amount of nitrogen flowing into the Sound would drop by 58.5 percent. Nearly 15 years and $617 million in sewage treatment plant upgrades later, it's difficult to gauge how effective that nitrogen reduction plan has been - and there are still disagreements among experts on how best to restore the Sound. A recent report by the federal Environmental Protection Agency's Long Island Sound Study says that nitrogen flowing into the Sound has been reduced by 20 percent - or by an average of 40,645 pounds a day - since 1994. But another report released last month by the Connecticut Council on Environmental Quality shows that the number of square kilometers in the Sound with enough dissolved oxygen to support aquatic life has risen and fallen sharply in the last 15 years. In 2006, the area affected by hypoxia - a condition caused by excessive nitrogen - was slightly larger than in 1991. Despite the large area still suffering from hypoxia, many officials and advocates say nitrogen reduction is critical to improving the health of the Sound. Most say it is necessary that in the coming weeks the state approves funding to replenish the Clean Water Fund, which provides grants and loans to municipalities to upgrade their sewage treatment plants. In recent years, the fund was emptied for projects not related to sewage treatment. But the emphasis on nitrogen reduction and sewage plant upgrades may not be the prescription to save the Sound, say some advocates. Staying the course Though large areas of coastal waters are still drained of oxygen, Mark Tedesco, director of the Long Island Sound Study, said he has begun seeing improvements in areas most affected by hypoxia - though he cautioned that he doesn't expect to see a "linear response" to nitrogen reduction. "Do we see less nitrogen getting into the Sound? Based on the monitoring program, we are seeing lower concentrations in the Sound," Tedesco said. "Are we seeing less plant production as a result of reduced nutrient levels? Yes, we are. There's evidence that nitrogen is decreasing in some of the hot spot areas - waters off of Stamford, and moving west from there." Tedesco pointed to two potential culprits for the Sound's still-decreased dissolved oxygen levels: Nitrogen pollution stored in the Sound's sediments and the region's increasingly warmer weather. As the Sound warms, it separates into two layers: Cooler water remains at the bottom, while warmer water rises to the surface. The warmer the water gets, the less oxygen it holds. But that top layer also seals off the cooler water, preventing oxygen from reaching the bottom.Ê "We've had some of the hottest years on record," Tedesco said. "That can exacerbate hypoxia." Since 1994, 39 of the 104 sewage treatment plants that empty into the Sound have been retrofitted with nitrogen removal technology, according to the Long Island Sound Study report. Had those treatment plants not been upgraded, hypoxia in the Sound today could be far worse, Tedesco said. Terry Backer, head of the nonprofit Soundkeeper group, agreed that sewage treatment and nitrogen reduction has been good for the Sound. He cited recent research by Ellen Thomas, a scientist at Yale University, that shows that nitrogen pollution - and possibly warmer water - is fundamentally changing the Sound's food chain. Diatoms - a single-celled, microscopic algae that has, for thousands of years, been at the base of that food chain - are made of nitrogen and silica. But the excess nitrogen has made the Sound unfit for diatoms, causing a surge in blue-green algae - which thrive on nitrogen, but don't need silica. Jellyfish feed on the latter, but the shellfish and fin fish that have traditionally populated the Sound don't. Another critical piece of the sewage treatment equation, according to Tom Andersen, author of "This Fine Piece of Water: An Environmental History of Long Island Sound," is getting New York City to begin removing nitrogen from wastewater plants that dump sewage into the East River, much of which flows into the Sound. In 1998, the city agreed to reduce its nitrogen levels - the same year as New York state and Connecticut - but shortly after backed away from its agreement. It wasn't until early 2006 that, after years of litigation with New York state, the city agreed to lower its nitrogen releases. The city was given until 2017 to fix its nitrogen problem, while the rest of New York state and Connecticut still have until 2014. In a statement, the New York City Department of Environmental Protection said it is "spending millions to upgrade its plants." Despite repeated requests, the agency did not provide specifics on those upgrades. An alternative? Art Glowka, a shellfish commissioner in Stamford and a longtime advocate for the Sound, is perhaps the fiercest critic of the nitrogen reduction plan. "Chemically clean water is not biologically productive water," he's fond of saying. "You can't grow fish in a bathtub." Looking at an old tidal map of New York Harbor, he points to a line that curves across the East River. "The river flows to the Sound about one hour, then it goes back out," he said. "There's a squiggle line where Throgs Neck Bridge is. . . . That's where the tides meet." His hypothesis that New York City's nitrogen doesn't flow to the Sound isn't his only beef with the restoration plan. Unlike the diatom research, Glowka said it's a lack of nitrogen that is hurting the Sound - not an excess of it. "If you're only scenario is reducing nitrogen, you starve plankton. You starve the ecosystem," he said. Starving the plankton reduces its size and drives out the fish that have traditionally fed on it, he said. "Since they're obsessed with clean, clean, clean, this is where we are now," he said. "All our native populations have decreased dramatically, like winter flounder and blackfish. Until the last couple of weeks, you didn't even see any birds out there." Yet Gary Wikfors, a fish biologist with the Milford branch of the federal National Oceanic and Atmospheric Administration and a member of the Long Island Sound Study management committee, said he has not seen any evidence of shrinking plankton, nor has he seen the blue-green algae mentioned by Backer. "The cast of characters has not changed very much. The same things come in the spring that came in 1955. It tends to be the same flora," he said. "That's one of the issues with any discussion of nitrogen. Is it going to change what phytoplankton is there? There's no strong evidence that it's changed." Wikfors, however, has his own problems with the restoration plan. He said the bulk of nitrogen reduction funds shouldn't be spent only on sewage treatment upgrades. Fish farms are an equally plausible solution and have been used in areas facing similar nitrogen problems, he said. Shellfish would soak up the nitrogen. And once harvested, the nitrogen would be removed along with the shellfish. These shellfish would not be harmful for consumption because "protein is 16 percent nitrogen by weight," he said. "It's not only safe, it's necessary," he said. Ê Wikfors is skeptical of another central pillar of the Long Island Sound Study restoration plan: that excessive nitrogen has spawned algae blooms in the Sound, which has in turn fueled hypoxia. "That hasn't happened. It's not supported by scientific data," he said. "I study algae blooms. I have to go to the Chesapeake Bay to study them. I can't find them in the Sound." Asked whether or not he thought spending millions on sewage plant upgrades is money well spent, he said: "I think nitrogen reduction is not the only step to restoring the Long Island Sound." Few dispute that. Backer compared restoring the Sound to both peeling an onion and putting together a giant jigsaw puzzle. As it's repaired, each piece of the restoration plan - such as stormwater management and sprawl control - needs to be plugged in correctly, he said. Robin Kreisberg of Save the Sound said that sewage treatment is like the low-hanging fruit of a tree. "It's not even clear we have been making progress because there's been so much development," she said. "It has to be a more holistic approach." Although Tedesco said upgrading sewage treatment plants is still a top priority in repairing the Sound, he said a "holistic" strategy is what the Long Island Sound Study has been working on. "I think everyone recognizes that restoring and protecting habitats is key," he said. "We need to improve how we're managing land use and development, so that we reduce runoff that gets into the Sound. That is all certainly very important." |
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