Using DNA to curb water pollution and reopen Cutchogue creek complex

08/24/2013 10:00 AM |

CARRIE MILLER PHOTO | John Bredemeyer, a Southold Town Trustee and chairman of the shellfish advisory committee, takes a water sample for DNA analysis from the Cutchogue Creek Complex.

Members of Southold’s shellfish advisory committee have been researching local creeks to identify specific sources of pollution and fecal bacteria that enter the waterways from septic tanks and stormwater runoff. Their research is part of an effort to reopen shellfish harvesting sites around town.

The committee has been working with the state Department of Environmental Conservation in hopes of reopening the Cutchogue creek complex, which was closed in 2004 due to water quality concerns, town officials said. Nine committee members have even been trained by DEC officials to collect water samples needed by the state.

So far two creeks – Wickham and Mattituck – have improved enough to possibly be reopened for shellfishing, said committee chairman and town Trustee John Bredemeyer.

While the committee waits to hear back from the DEC to see if restrictions will be lifted in those areas, committee members are stepping up their efforts to determine if other creeks have also improved enough to reopen.

Samples are being collected from East Creek, Mud Creek and Broadwater Cove and will be tested using DNA analysis, an “emerging science” in understanding water contamination, Mr. Bredemeyer said.

Sampling must be done 36 to 40 hours after heavy rainfall, while tides are going out. The goal is to get samples of runoff from nearby roads, homes and septic tanks, to see what kinds of fecal bacteria are entering Cutchogue’s creeks.

Mr. Bredemeyer said the analysis will identify sources of bacteria, whether it be human waste from nearby septic systems or scat from geese or swans.

“We’re on the hunt,” he said. “The waste of four or five geese could be equivalent to the waste of one human.”

The results with help the town determine if anything can be done to stop pollution from entering creek waters, he said.

“It would be difficult to diaper all the animals, but if we have trouble with runoff from public works or homes, those are areas that can be looked at and updated with improvements,” Mr. Bredemeyer said.

The town has contracted with researchers at Cornell Cooperative Extension to run the DNA analysis, which comes at a hefty price. Processing of 15 samples costs the town just under $11,000, Mr. Bredemeyer said.

To fund the testing, the town has increased mooring fees for boats in town creeks for the first time in more than five years, Mr. Bredemeyer said.

The cost for a small mooring is now about $150, he said.

Cornell stormwater specialist Scott Curatolo-Wagemann said a DNA footprint is made from the fecal bacteria in water samples.

He compares the DNA footprint to a library of 14 different species, identifying which animal it most closely matches, Mr. Curatolo-Wagemann said.

“As far as I know there is no one else on Long Island that has this,” he said. “We have had to go out and collect the animal scat samples and isolate the bacteria to build a profile of what the DNA looks like.”

Mr. Bredemeyer said the committee has become frustrated that the creeks have remained closed for so long, and are making the extra effort to ensure that shellfishing restrictions can be lifted in the future.

“The shellfishing industry employs a lot of people,” he said. “We want to get to the root of the problem so they can start working again.”

Baymen’s Association president Nate Andruski said the creeks might be commercially exploitable areas for fishermen.

“It would give us more options,” he said. “We’re pretty limited as it is. We don’t have huge areas of open town waters out here like Southampton and up-island.”

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