As the weather starts to heat up, Long Islanders headed to local beaches may have to share the water with an unwanted visitor: toxic algae.

Last year, toxic algae was found in nearly every major bay and estuary across Long Island, according to data compiled by the Nature Conservancy, a national environmental organization.

President of Friends of Bellport Bay, Thomas Schultz, explained that the excess algae blocks sunlight from penetrating the water column, thereby inhibiting photosynthesis. “We do have some bodies of water like that where there’s hardly any life at all because there’s no oxygen, there’s no photosynthesis,” he said.

This problem is due in great part, to an excessive amount of nitrogen-heavy sewage seeping into local waterways.

A 2011 study published in the Journal of Coastal Research found that outdated septic and cesspool systems accounted for 69 percent of nitrogen in the Great South Bay.

“Seventy percent of Suffolk County’s population is just using these septics which allow for untreated sewage and nitrogen to enter into groundwater which discharges into freshwater lakes and also our bays and estuaries,” Adrienne Esposito, Executive Director of Citizens Campaign for the Environment, said. “We’re not treating our sewage and we’re allowing it to mix with our drinking water supply and our surface water. That’s crazy.”

In an attempt to lessen the problem, the [read more]