For many New Rochelle residents who live near Beechmont Lake, the sight of bright green algae blanketing the water is a painful reminder of the true cost of environmental damage.
Westchester County and New York State recently pioneered environmental legislation intended to reduce unsightly green algae blooming across our lakes by limiting the use of phosphorus-containing fertilizers. But the new laws, some of which go into effect just a few months from now, may be too little, too late.
Mayor Noam Bramson lives near the lake. “I live only a few hundred feet from Beechmont Lake and observe its condition with distress and frustration on a daily basis. The ecology of the lakes and waterways within New Rochelle — and throughout our region — is stressed by a variety of factors. Excess nitrogen and phosphorus, for example, makes its way into lakes from fertilizer run-off and a variety of other sources.”
The website of the New York Public Interest Research Group (NYPIRG) notes that “Phosphorus (P) occurs naturally in living things and soil, but when too much enters streams and lakes it stimulates the growth of algae and results in an algae bloom.” It is estimated that just one pound of phosphorus can produce up to 500 pounds of algae.
According to the New York State Department of Environmental Conservation (DEC), focusing on ways to limit phosphorus in lawn fertilizers is important because most soils in the state already contain sufficient phosphorus to support turf grass growth without additional phosphorus in fertilizers. In addition, phosphorus in lawn fertilizer can account for up to 50% of the soluble phosphorus in storm water runoff from lawn areas.
New rules on phosphorus in fertilizers will go into effect January 2012, including a ban on using lawn fertilizer between December 1 and April 1 and a ban on the use of fertilizer containing phosphorous unless you are just starting a new lawn or unless a soil test actually proves your lawn lacks adequate phosphorus.
How can you tell if your fertilizer is phosphorus-free? All fertilizer bags list 3 numbers on the label that are the percentages of 3 key nutrients in the product, always listed in order as Nitrogen ( N), Phosphorus ( P) and Potassium (K). So you might see a bag with 20-10-20, for example, meaning 20% Nitrogen; 10% Phosphorus, and 20% Potassium. Look for a middle number of zero ( 20-0-20) and that will be phosphorus-free.
New Rochelle’s recently adopted Sustainability Plan, GreeNR, includes “specific recommendations for improving water quality and restoring lake depth,” according to Mayor Bramson. But the plan is focused on the long term and doesn’t address the immediate algae problems.
“The cost of dredging a lake and then disposing of material is quite high and likely dependent upon grants,” says the Mayor. “Smaller steps, such as dredging Beechmont Lake’s forebay have already been attempted, with very limited effect.”
So what can we really do? The Commissioner of Public Works in New Rochelle, Alex Tergis, who has been on the job for just 9 months, says he is currently researching control methods and believes that the recent heat wave has accelerated the algae bloom this year. “The best prevention,” he explains, “is proper control with regard to the application of fertilizers, and dredging, which is very costly and a highly restricted type of project in terms of methods and timing, due to the aquatic life it affects.”
One step that has been taken by other communities is for neighborhood groups to work with city government to consider the installation of aerators that might partially address the problem. The aerators that were installed in the lakes in front of the New Rochelle High School seem to be effective, but residents say aerators installed at Glenwood Lake do not seem to have solved the problem there. Paine Lake and Carpenter Pond also seem to have algae blooms that are stronger this year.
Perhaps a neighborhood task force might be able to come up with some new ideas and viable solutions. Any volunteers to save our lakes?
Joyce H. Newman is an Emmy Award-winning environmental journalist, educator, and gardener. She holds a Certificate in Horticulture from The New York Botanical Garden, and is a tour guide there.