CARRIE MILLER PHOTO | Suffolk County Water Authority assistant superintendent Warren Jensen.
In an effort to reduce the impact of chemicals on Long Island’s groundwater, the Suffolk County Water Authority wants to learn more about how North Fork farmers cultivate their land.
The public agency has contracted Cornell Cooperative Extension of Suffolk County to gather data from local farmers about their agricultural practices, hoping to better understand if and how the chemicals they use are reaching groundwater.
“We want to have a better handle on things like what crops are being grown and what products are being used to grow those crops,” said Carrie Meek Gallagher, chief sustainability officer for the SCWA.
A farmer’s irrigation and product storage practices can each play a role in whether or not chemicals are leeching into the groundwater, she said.
After gathering the information, Cornell scientists will make recommendations on how farming practices might be improved to protect water quality in the future, Ms. Gallagher said.
Dale Moyer, agriculture program director at the county extension said researchers are in the beginning stages of planning the study, which they hope to start sometime early next year.
“Based on what we learn and understand, we may come up with additional practices to avoid or minimize any impacts from the pesticide use,” Mr. Moyer said. “Now is the time when the farmers aren’t so busy, so there can be some conversation and discussion of practices of what’s being done and what can be done.”
He said there are many materials farmers use that do not make their way into groundwater, so researchers hope to also get a broad understanding of products working well in the area.
The program, which will cost about $5,700, will focus on farms surrounding the agency’s well field off Route 48 near Mill Lane in Peconic. The well field, one of 17 overseen by SCWA, has seven individual wells, Ms. Gallagher said.
It is one component of a long-term plan the authority is working on to continue supplying North Fork residents with safe drinking water — free of pesticides, herbicides and fertilizers used in agricultural production, according to SCWA officials.
“Currently, 27 out of 56 authority supply wells on the North Fork are on treatment for pesticide-related contamination,” said SCWA chairman James Gaughran. “As the equipment needed to filter out these chemicals is extremely expensive, it’s in the best interest of our customers to take whatever steps are possible to reduce the amount of these chemicals entering the aquifer system.”
This year, SCWA installed a filter known as a granular activated carbon system, at one of the seven wells in the Peconic field. The system, which holds 10,000 pounds of carbon, costs about $750,000, not including maintenance, said Warren Jensen, an assistant superintendent with the agency.
Trace amounts of at least five different chemicals commonly used in agriculture had been detected in groundwater at the Peconic site, according to 2012 SCWA data. They include nitrates (nitrogen) and metalaxyl, two of the substances most widely contested by environmental advocates.
Many of the pesticides or fertilizers that have been detected in Long Island’s groundwater are what the agency calls legacy contaminants that are no longer available for use on Long Island, Ms. Gallagher said. Some of the detected compounds, however, are still being used in fertilizers and pesticides on Long Island.
If SCWA finds the information gathered by Cornell useful, it may extend the program to each of its additional well fields.