Overview
Pathogens are viruses, bacteria, algae, and protozoans that cause diseases in humans, other animals or plants. Pathogens that may be found in marine waters include those causing gastroenteritis, salmonellosis, and hepatitis A. Pathogens can enter marine waters via untreated or partially treated human sewage and possibly by way of wild or domestic animal waste. Humans may encounter pathogens through direct contact with contaminated water, ingestion of contaminated water, or consumption of raw or partially cooked shellfish harvested from contaminated waters. Pathogen inputs to the Peconic Estuary are a concern because of the potential human health risks and the economic losses associated with the closure of shellfish beds and beaches.
Because measuring concentrations of specific pathogens in seawater is so difficult, scientists use indicators as a proxy for pathogens commonly found in the intestines of warm-blooded animals. The most common indicators are fecal and total coliform bacteria. Excessive levels of coliform bacteria are generally found in areas where the water exchange or tidal flushing is limited and runoff from the surrounding land is high.
Sources of pathogens in the Peconics
Stormwater runoff carries a multitude of nonpoint source pollutants and is the largest contributor of pathogens to the estuary. Coliform bacteria from undeveloped land are most likely from wildlife (including waterfowl) while those from developed areas may be from domestic animals, livestock, and/or poorly functioning septic systems or cesspools. More than 28 stormwater runoff abatement projects were implemented between 1993 and 2001. In addition to stormwater runoff, another small but possibly significant contributor of pathogens is sanitary wastewater from boats, particularly in the enclosed waters around marinas and mooring areas. To remedy this problem more sanitary pump-out stations have been installed at marinas over the past several years. Also, the Peconic Estuary Program has secured a ‘Vessel Waste No Discharge Area’ designation for the entire Peconic Estuary.
Pathogens can also originate from point source discharges. Point sources in the Peconic Estuary include effluent from sewage treatment plants and the Corwin Duck Farm on Meetinghouse Creek.
Status of pathogens in the Peconics
Approximately 4% of the Peconics is closed to shellfishing (5,222 acres) for reasons including water quality concerns. An additional three acres, in Pipe's Cove, where closed to seasonal shellfishing in 2007. Water quality in larger bodies of water in the Peconics support unrestricted shellfishing, unlike Flanders Bay and some more sheltered and poorly flushed creeks and embayments.
The Peconic Estuary boasts over 450 miles of shoreline and 31 bathing beaches permitted by Suffolk County. Since 1980, there have been only 12 bathing beach closures (11 of which were precautionary).
PEP pathogen management goals
- Minimize health risks due to human consumption of contaminated shellfish
- Minimize closure of beaches and shellfish beds due to pathogens
- Develop and implement plans to reopen closed shellfish beds
What the PEP is doing to reduce pathogen loads
The PEP has proposed a concerted effort to reduce the pathogen load to the Peconic Estuary, but controlling runoff from existing development is an extremely expensive and often complicated proposition that needs to be addressed over time. Many road runoff mitigation projects have been completed or are underway across the Peconic Watershed, undertaken at the State, County, town, and village levels. In June 2002, the entire Peconic Estuary was approved as a Vessel Waste No Discharge Area (NDA), making vessel waste discharges illegal. Numerous free municipal pump-out boats and shore-based facilities aid compliance with the NDA.
Other important management components are the New York State Shellfish Sanitation Program and the bathing beach monitoring program run by the Suffolk County Department of Health Services. Because measuring the concentration of specific pathogens in seawater is so difficult, scientists and regulators use fecal and total coliform bacteria, as well as enterococcus bacteria, as indicators of pathogen contamination. Managers use the monitoring data to establish shellfish harvesting and bathing beach closures necessary to protect public health.
