Periods of high rainfall have led to the closure of a growing number of beaches along the Long Island Sound as untreated sewage, waste and fecal bacteria wash onto the region’s pristine shores, according to a report scheduled to be released Friday.
The nonprofit environmental organization Save the Sound also ranked seven Suffolk County beaches along the 110-mile Long Island Sound as among the best for overall water quality and safe swimming conditions.
The “Long Island Sound Beach Report,” which will be publicly released Friday at a news conference in Oyster Bay, found the Sound’s 204 swimming beaches in New York and Connecticut were deemed safe for swimming 93.3 percent of the time between 2016 and 2018, higher than the national average.
But the analysis, based on data submitted to the Environmental Protection Agency by the health departments of local municipalities, also points to troubling trends for those planning to visit North Shore beaches during the final months of summer.
Failing wastewater infrastructure, sanitary sewer overflows and stormwater runoff, often triggered by periods of high rain, are increasingly causing area beaches to be closed for swimming. The overall failure rate of Long Island Sound beach samples jumped from 5.4 percent in dry weather to 11.1 percent following rain, the group found.
The report found the quality of water varied significantly from beach to beach — even those in proximity to one another — as pollution tends to be highly localized.
“Pollution at Long Island beaches is a local problem with issues coming from the local community,” said Tracy Brown, director of Save the Sound. “And if you don’t want to swim in fecal matter, pollution needs to be handled on the local level.”
At coastal beaches on Suffolk, stormwater runoff is the predominant source of bacteria-laden water, according to county Health Department officials. Stormwater runoff typically becomes contaminated with bacteria as it flows across roadways, yards and parking lots. The polluted stormwater then travels through storm drains or sewer pipes and into local waterways that impact area beaches.
The most common risk when swimming in polluted waters is coming into contact with, or ingesting, disease-causing microorganisms such as fecal bacteria, viruses and other pathogens, the report said. Swimming in bacteria-contaminated water can cause gastrointestinal illness and infections of the eyes, ears, nose and throat.
With the Sound region expected to experience increased rainfall over the coming decades because of climate change, local governments should invest in environmentally friendly sewage infrastructure, said Gregory O’Mullan, an environmental microbiologist and professor at Queens College.
For example, Save Our Sound recommends eliminating all remaining combined sewage overflows — which collect rainwater runoff, domestic sewage and industrial wastewater in the same pipe — around the Long Island Sound.
“Many of these issues may be seen as a low priority,” said O’Mullan, who consulted on the report. “But for a lot of these coastal communities, their identity is based on their location. And water quality can be a serious quality-of-life issue.”
Rep. Thomas Suozzi (D-Glen Cove) said he would continue to push for federal dollars to protect and improve the Sound.
“We have made incredible strides over the last 20 years,” Suozzi said. “We cannot let our guard down and we must continue to reduce nitrogen runoff and improve stormwater management and sewage infrastructure.”
New York’s top beaches on the Sound, ranked on how often their water was deemed safe for swimming and its level of contamination, included 10 from Suffolk, the report found. They include Hobart Bay and Hobart Inlet/Sound in Northport, Port Jefferson East, Port Jefferson West and Belle Terre beaches in the Town of Brookhaven, and Iron Pier Beach in Jamesport and Mattituck Breakwater Beach. Suffolk beaches with the lowest water quality grades include Crescent Beach in Huntington and Scotts Beach in Miller Place, the report found.
In Nassau, high marks went to Bar Beach in Port Washington and Creek Beach in Lattingtown, while low grades went to Crescent Beach in Glen Cove and Lattingtown Beach. Most Long Island beaches are tested once a week during swimming season.
While a 10-year review of water quality data generally showed higher grades in the eastern Sound and lower to the west, there was little constant from year to year, the group found. For example, 2018 showed the largest decline in water quality at eastern Suffolk beaches. The reason for the decline, the report said, is not clear.
In addition to the report, Save the Sound also unveiled an upgraded website with more than a decade of water quality data for Long Island Sound beaches.