As Long Island’s bays are once again staining red and brown with blooms of algae, scientists from Stony Brook University pitched a plan to Southampton Town officials this week that they say could help municipalities more efficiently focus their dollars on water quality problems to optimize the benefits of every dollar spent.
The scientists told town lawmakers that they can help the town develop maps of the watersheds to local bays and harbors that will show where the most aggressive efforts to reduce the flow of nitrogen from residential septic systems should be focused to realize the greatest impact on the factors that are believed to contribute to devastating algae blooms.
“We can build a model that essentially figures out how to lessen the intensity of the algal blooms to have the maximum positive effect in the environment,” said Christopher Gobler, Ph.D., a professor at Stony Brook and expert on the algal blooms that have plagued the East End’s bays since the mid-1980s. “Once it is built, we can use models to define what is needed to dial it down to the point where there is either no algal blooms or less intense blooms, less deleterious to the environment.”
The plan, which would include an online model that homeowners could use to calculate their own property’s “nitrogen footprint,” would cost $95,000, primarily directed to the salaries of two researchers who would do the detailed mapping of nitrogen flows and environmental factors and develop the computer management models.
Just a day after making the pitch to the Town Board last Thursday, August 7, the Stony Brook scientists announced that water testing had shown that a red algae bloom had once again emerged in local bays, at densities not seen in years.
Over the last several years, Stony Brook researchers studying the algae blooms have issued a series of reports on the conditions of Long Island’s bays that, they say, has shown direct ties between increasing amounts of nitrogen flowing into local bays, primarily from residential septic systems, and the number and intensity of the algae blooms that have swept the region in summer, killing fish and shellfish and hobbling local fisheries.
Biologists from Stony Brook and other organizations have said that the only way to effectively combat the proliferation and devastation of the blooms is to greatly reduce the amount of nitrogen in the water. But on the broadest scale, such a goal is lofty, complicated and expensive.
“It’s mind-boggling how much it is going to cost,” Southampton Town Supervisor Anna Throne-Holst said. “Who is going to pay for it? Is there a way to do something that gets us our biggest bang for the buck?”
Southampton Town last year began a program to help homeowners pay for replacing failing septic systems, which allow high levels of nitrogen to seep into groundwater flowing toward bays. Such efforts are expensive—thousands of dollars per property—and funding has been hard to come by. The town has said it needs to be able to direct what support it can muster to properties that will pay the biggest dividends.
Dr. Gobler told the board last week that in certain areas septic upgrades, indeed, should be high priority. But in others, like areas where strong tidal currents flush in clean water and dilute nitrogen loads, the impacts of leaking septics may not be quite as disastrous.
“In certain areas the only solution might be that everything needs to be on alternative [septic] systems,” he said. “But in others it may be that the [tidal] flushing means that it can really survive on tertiary systems and we could put the attention on another area.”
On some large properties, especially those used only seasonally, septic inputs may not be the biggest contributor of nitrogen. In such cases, other efforts, like reducing the amount of fertilizers used on lawns, may be more effective in reducing nitrogen. For those properties, directing public outreach and education would be more effective than encouraging septic upgrades. Ms. Throne-Holst said that if the town chose to fund the Stony Brook modeling plan—other groups have been working on similar priority mapping—it would not be funded with tax dollars but with funds from the town’s dedicated Water Quality Improvement Fund, which draws revenues from a variety of fees and contributions from development projects.
“We have to be careful about how we spend, but all the sleuthing out has to be done,” the supervisor said. “This would really be a tangible contribution that the town could make and a good way to direct dollars toward this situation.”