On Tuesday morning, a public health sanitarian from the County Health Department went to the south end of Lake Montauk to test the water at the popular beach there, as well as the water in two streams that enter the lake nearby.
The testing is related to swimming safety and not to the possible contamination of shellfish. East Hampton Town Supervisor Bill Wilkinson asked for the test last week and said he would use the results to decide whether the beach should be closed to bathers. Testing done by the County Health Department six years ago found contaminants in tributaries.
Mr. Wilkinson said he understood that tests of the water where people swam were made at the time. “I’m interested in the whole south end,” he said.
The State Department of Environmental Conservation closed the entire lake to shellfishing as a result of the heavy rainfall on Sunday and Monday. Normally, the south end (where the water was tested for swimming safety on Tuesday) is closed to shellfishing in the summer months, as are areas around the Montauk Lake Club, the east side of Star Island, and in Coonsfoot Cove in the lake’s harbor area.
Tuesday’s test was one result of a well-attended Aug. 10 meeting of the town’s Lake Montauk Watershed Advisory Committee. During the meeting, Kim Shaw, a senior public health sanitarian with the Health Department and a county liaison to the Peconic Estuary Program, surprised some committee members by revealing that the Health Department had a record of swimming-related water testing until 2005.
The data will be added to a recent study done by the Cornell Cooperative Extension that identified, through DNA, the sources — animal as opposed to human — of fecal coliform bacteria found in water around the lake.
In a phone interview on Monday, she said the county had not tested the waters at “South Beach” since 2005 because that year the town stripped the beach of its lifeguard. Once a beach is no longer considered a certified bathing beach — with a guard and public toilets — the county stops testing.
Ironically, the beach had been equipped with an advanced compostable toilet in the late ’90s compliments of a grant from the Environmental Protection Agency via the Peconic Estuary Program, according to Larry Penny, the town’s director of natural resources. But, without a guard, a swimming-prohibited sign went up.
The sign was not meant to suggest the waters were unclean, he said, only that the beach was unguarded. Mr. Penny stressed that tests of water quality as they pertained to the risk of eating shellfish harvested from an area were different from tests to determine swimming safety.
The State Department of Environmental Conservation uses the level of coliform bacteria associated with fecal matter to determine the relative safety of shellfish. The County Health Department looks for enterococcus bacteria, intestinal flora that can cause illness.
Bill Hastback, a shellfish biologist with the D.E.C., said the difference in testing protocols was rooted in standards for bathing beaches that were changed by the Environmental Protection Agency in 1986. In the past, the County Health Department tested for the presence of both organisms.
“Shellfish water quality standards are super strict. If areas are open to shellfishing, they’re probably suitable for bathing beaches,” Mr. Hastback said. But, if an area is closed to shellfishing, it does not follow that it should be closed to swimmers. When the presence of fecal coliform was used as a standard, the allowable limit for swimming was 200 parts per 100 milliliters of water, rather than 14 parts per 100 milliliters for shellfish safety.
According to Mr. Penny, existing Health Department test results have shown the presence of enterococcus bacteria coming from a stream that enters the lake on its southeast end. There are three tributaries to the south end, the stream on the east, another stream on the west that flows from the Ditch Plain community, and a culvert that passes under Montauk Highway, also adding to the flow from the east.
The Cornell Cooperative Extension’s study of 14 sites around the lake found that those located near the southernmost tributaries were the only ones to contain human fecal coliform bacteria.
Mr. Penny stressed that while there were concerns about the lake’s south end, “all along people have been saying the lake water has improved. There have been no increased [shellfish] closures since the ’80s. There have been in other places — Three Mile Harbor and Hog Creek.”
Kevin McAllister, the Peconic Baykeeper, is a member of the lake committee. He said on Tuesday that there remained “looming questions” about water quality. “Let’s be honest about these waters. With respect to bathing beaches, even unguarded swimming holes, they are recreational bodies of water. There’s kayaking, paddleboarding. Let’s see if they’re safe.”
He said he had spent over a year trying to convince the Village of Sag Harbor to monitor Havens Beach more closely. “The county kept saying it was safe, and I kept insisting that the water was not being tested after heavy rainfalls that bring in the pollutants.” His independent testing of “the pulses of rain,” in cooperation with Southampton College, finally convinced the village to take action.
He said he wanted Lake Montauk to be subjected to the same kind of comprehensive testing. “If we’re not responsive to the rain event pulses, routine testing schedules will miss what’s really going on,” he said, adding that testing for pesticide and nitrogen from fertilizer should be put on the front burner.
Tuesday’s testing was an example of how the lake committee had found its rhythm, Supervisor Wilkinson said that day. “The committee’s taken great leaps in the last couple of months. It’s started to click as a group of concerned citizens not individuals. The lake is the beneficiary.”
He announced that a subcommittee had been formed, the Lake Montauk sustainability committee “to raise funds privately.” Mr. Wilkinson said the umbrella committee would decide on how the money raised is disbursed. “I think it’s great.”
Bill Grimm, a commercial fisherman who helped organize the subcommittee, has suggested holding a fund-raising event at the Inlet Seafood restaurant before the end of the summer season.