Weekly report: Long Island water quality generally good

Water quality is rated mostly good for Long Island bays, harbors, rivers and inlets, according to a report of weekly samplings.

Out of 29 shore locations tested Monday, 17 received good ratings, meaning clear water, no or low levels of algae and/or bacteria from human or animal waste, and hospitable conditions for fish and shellfish. Ten were rated fair, and two, poor.

That’s according to the Long Island Water Quality Report, a weekly score card issued from Memorial Day to Labor Day. It’s created by Chris Gobler, professor of marine science  at Stony Brook University and director of the university's New York State Center for Clean Water Technology, and his team of more than 20 students and scientists.

“As we move through June, water quality is generally good or fair,” he said.

Still, two spots were tagged as poor — the Forge River and Western Moriches Bay, both with reduced water clarity, low levels of oxygen and high levels of harmful algal bloom. A high level of fecal bacteria was also found in the Forge.

In addition, the middle of the Great South Bay was deemed to be fair, due to low oxygen and water clarity, elevated levels of algae, along with signs of brown tide starting to emerge.

The area in 2017 saw “record-setting brown tide,” Gobler said. That year a coffee-colored bloom in the Great South Bay lasted for 10 weeks, the longest and most intense documented here. Brown tide poses no danger to human health, but can be harmful to shellfish.

The aim of the weekly water-sampling project, started in 2014, is to provide regular snapshots of ecosystem health, with an eye to how well locations are supporting — or not supporting — robust fishing and shellfishing activity.

While the beach crowd may find some basics useful — water temperature and clarity assessments — this is not the place to go to see what locations are up to snuff for swimming and splashing around. Look, instead, to official calls from county health departments on where to swim or not, Gobler said. And, for any curtailment of shellfishing, the state Department of Environmental Conservation is the go-to official source.

Sampling is done on Mondays, as six teams “fan out across Long Island, collecting water samples, making measurements, and downloading data from logging devices, like oxygen meters,” he said.

From all that, the good, fair and poor scores are determined.