A New Look at the Mill Pond’s Problems
(09/17/2009) The bad news is that Water Mill’s Mill Pond continues to have significant problems with algae, carp, and excess nitrogen and phosphorous. The good news is that after 20 years of such problems and a decade of outcry from the community, eventually . . . possibly . . . maybe even soon . . . something will be done about it.
Mill Pond and Mill Creek’s intersection with Montauk Highway in Water Mill is a significant gateway to the area many people think of when they refer to “the Hamptons.” But for almost as long as anyone can remember, the clear Mill Pond waters people once ice-skated on have been besieged by algae blooms.
A massive fish kill in late September last year clogged the water with the smelly carcasses of an estimated 2,500 pounds of fish and prompted the Southampton Town Trustees to commission a study of the causes and to find possible solutions.
Fred Havemeyer, the trustee responsible for the bodies of water in the area of Southampton Town from the Shinnecock Inlet to Ocean Road in Bridgehampton, addressed the Water Mill Citizens Advisory Committee and residents who live on the pond Monday night. He called the fish kill a “classic situation where excess nutrients caused an excessive algae bloom. The first cold night causes the algae to die off. It’s a bloom like that from the changing temperature. The dying algae suck all the oxygen out of the lake. It’s a classic fish kill. It’s happened in Lake Agawam and Cooper’s Neck Pond and now Mill Pond. It’s a canary in a coal mine.”
Mr. Havemeyer said residents will not have to worry about another fish die-off like last year’s. “There’s not any fish left after the kill.” Part of the work to determine the health of the pond will include a fish count to find out what species are left — probably just carp and goldfish, which can survive such conditions.
“Once we turn the lake around, we will reintroduce them into the lake,” he said. “We have a stock ready, we just can’t do it yet.”
Although both nitrogen and phosphorous tend to cause the conditions seen at Mill Pond, Mr. Havemeyer and Jim Walker, an environmental consultant at Inter-Science in Southampton, said phosphorous is probably the biggest culprit. Phosphorous is a byproduct of stormwater runoff or of waste in septic systems that enters the pond by seeping up from groundwater.
“It’s a limiting factor in a pond like Mill Pond. I expect it to be very high,” Mr. Walker said.
He and the trustees are also working with Christopher Gobler, an associate professor of marine science at Stony Brook Southampton and an expert in harmful algae blooms, and Lee Lyman, the head of Lycott Environmental of Southbridge, Mass., which offers expertise on pond and lake management.
According to Mr. Walker, Dr. Gobler has been studying Mill Pond since 2001 “and will share all work with us,” including data taken from 2005 to 2008.
This year’s problems were less severe because the spring and early summer were colder than usual and the blue-green algae did not develop until much later.
The trustees have made a concerted effort to reclaim Lake Agawam in Southampton and have had some success. They installed bubblers, which work well with the lake’s smaller size and can tap into the village’s electric system. They also reintroduced fish, such as largemouth bass, that eat young carp. The fish could also be a good population control for the carp in Mill Pond. The trustees hired a bayman to address Agawam’s carp problem, and he netted 4,500 pounds in one season, according to Mr. Havemeyer.
The carp, which have been stocked in the pond since Colonial times, eat plants that are beneficial to the pond’s ecosystem. The slow-moving fish are easy to catch. They ensured the settlers would have food, and they are still popular with some people, particularly at Christmastime.
Mr. Havemeyer encouraged those who live on the pond to create buffers on their properties or widen existing ones “so runoff doesn’t make it into the pond.” He pointed out that Marty Shea, the town’s chief environmentalist, has guides to native plants. They are in his office for anyone who wants more information.
The easy way to create a buffer is simply to refrain from mowing grass near the pond’s edge, Mr. Havemeyer said. “Then the natives come in. Buffers, buffers, buffers are the most important thing you can do. . . . Bottom line, the worst thing is when runoff goes to the water’s edge.”
One of the pieces of data Mr. Lyman wanted to collect was the phosphorous content of the water supplied through the Suffolk County Water Authority system. “Even sprinklers could be a cause,” Mr. Havemeyer said, because pond water is that sensitive.
Toni Maloney, who lives on the pond, asked about a test from two years ago that found that the water quality was dangerous for animals and not good for humans.
Mr. Havemeyer said he was not familiar with such a study. From the material he had read from Dr. Gobler, a person would have to drink 400 liters of Mill Pond’s water a day to be affected by it. “I didn’t think anybody was that thirsty,” he said.
Comparing Mill Pond to Big Fresh Pond in North Sea, Mr. Havemeyer said runoff was not a problem there because a majority of the houses were across the street from the water, whereas houses at Mill Pond were on the pond.
Residents were also concerned about the preponderance of water lilies, which make navigating the pond difficult. Mr. Havemeyer said water lilies are native to the pond and that Mr. Shea was opposed to “anything touching the water lilies,” which provide shade for the pond and a habitat for fish.
As long as a property receives a permit, the State Department of Environmental Conservation will allow a narrow channel to be cut through them from a dock to the open water. Once the pond is treated and the nutrient level decreases, the number of water lilies should return to normal. With the amount of fertilizing elements in the pond now, however, the water lilies are reacting as any other plant would to having an abundance of food.
Mr. Walker said the study he and the trustees are working on should be completed by Jan. 1. It will have recommendations and could allow for doing some cleanup work next spring and summer, depending on both financial factors and the D.E.C.’s permitting process.
Southampton Town Councilman Chris Nuzzi, who was at the meeting with Councilwoman Sally Pope and Bridget Fleming, a candidate for town board, said that he believed there was a role for the town board in cleaning up the pond. As the board is interested in allocating money for the project, he said, “we are in sync with the trustees.”