ATLANTIC CITY — Technicians were busy testing water samples from Atlantic County ocean and bay beaches at a laboratory here Monday, looking for signs of bacterial contamination.
If a beach’s water sample is too high for Enterococcus, a bacterium found in the digestive tracts of animals, an advisory is put out on the beach and new samples collected. If it remains high two days in a row, the beach is closed, said Atlantic County Utilities Authority Laboratory Director Michael Gille.
Since water quality problems usually happen after big rain events, it wasn’t surprising when 47 Jersey Shore beaches tested positive after sampling June 11, and advisories went out June 12. The previous week was unusually rainy, he said.
ATLANTIC CITY— Water quality advisories are in effect for beaches on Georgia Avenue and Miss…
But the next samples collected were all clear in Atlantic and Cape May counties, so no beaches in southeastern New Jersey were closed.
It’s all part of the state’s Cooperative Coastal Monitoring Program, Gille said. Testing is always done on Mondays, with results taking 24 hours. The lab also does wastewater and drinking water testing and is located at the ACUA wastewater treatment plant.
The water tested Monday came back fine Tuesday.
Generally high Enterococci counts are caused by animal droppings, said Gille. Dog, cat, bird and other wildlife waste gets swept up by stormwater runoff, into street drains that dump into nearby streams that end in the ocean.
But the real culprit is all the impervious surface — places rainwater cannot penetrate — in our highly developed state.
“On normal undeveloped ground, (the waste) percolates into the soil with the water and is broken down,” Gille said. But when you develop land, put down concrete and asphalt, water has to go somewhere else.”
Coastal areas are some of the state’s most developed areas, with homes packed tightly together on barrier islands, and little space for yards or planted areas.
“There are things people can do,” ACUA spokeswoman Amy Menzel said. “They can pick up their dog waste, and be mindful of what goes into the storm drain, which goes into the nearest body of water, not to the sewer treatment plant.”
They also can capture rainwater in rain barrels and reuse it in gardens, use green roofs as planting surfaces and generally avoid paving over their properties, she said.
The ACUA laboratory has been working with the Atlantic County and Atlantic City health departments on ocean and bay monitoring since 1985, Gille said. At first it tested for fecal coliform levels, but switched to Enterococci in 2004.
Its die-off rate is slower in salt water than fecal coliform, so it’s a more reliable indicator of water quality, Gille said.
The lab analyzes samples collected by health department staff and relays the data to the New Jersey Department of Environmental Protection and both health departments. They in turn issue advisories or closings when needed, Gille said.
Bacteria levels on most shore beaches after a storm are not truly dangerous, even if they are above the safe-swimming standard, said Bruce Friedman, director of the DEP’s Division of Water Monitoring and Standards.
Experts say when impervious surfaces make up 8 percent or more of the total landscape, waterways are at greater risk of degradation.
New Jersey, as a whole, reached that threshold in 2011, according to the National Land Cover Database. No other state has a higher share.
The most recent statewide figure is somewhere north of 12 percent, according to a 2016 analysis by the Rutgers Cooperative Extension Water Resources Program.
The Associated Press contributed to this report.