Environmental nonprofit Save the Sound has released its annual water quality report card, grading more than 50 bays and four basins of open water on the Long Island Sound. Scientists said the results are encouraging, but there’s still work to be done.
Ninety-eight percent of the open waters that were tested received a B grade or higher. Scientists credit improved stormwater drainage and reduced nitrogen pollution.
Dr. Jason Krumholz is an associate professor at UConn and the stewardship coordinator for the Connecticut National Estuarine Research Reserve. He explained the grading system.
“Indicators include dissolved organic carbon, which is a measure of the amount of influence on the system; Chlorophyll A, which is a measure of microscopic algae in the water; dissolved oxygen, which is critical to the survival of fish, shellfish; and water clarity, which is a matter of measure of how far light penetrates in the water,” Krumholz said.
Forty-two percent of the bays and harbors around the sound received a C grade or lower.
Peter Linderoth is the director of water quality at Save the Sound. He blamed nitrogen pollution for the instances of low water quality.
Nitrogen comes from fertilizer and aging septic systems that end up in the sound through stormwater runoff. Excess nitrogen in the water causes harmful algae blooms, which lower oxygen and plants and animals.
“We must continue investing in wastewater infrastructure improvements to protect these local waterways,” Linderoth said.
Most of the bays that got lower grades are located near New York City. But three that are located in Connecticut and Long Island received F grades: the inner Bridgeport Harbor, the Inner Norwalk Harbor and the Inner Manhasset Bay.
Data for the report card was provided by the Connecticut Department of Energy and Environmental Protection, the New York City Department of Environmental Protection and the Interstate Environmental Commission. The data was collected in 2023.
Another issue that threatens the sound is water temperature, according to Krumholz.
The average annual water temperature has risen 3.7 degrees since 1960, according to the Long Island Sound Study.
“While we've seen improvements over the last 16 years, climate change and continued population growth and coastal development threaten to undo some of the great work that's been done,” Krumholz said. “Rising water temperatures have a range of potentially damaging impacts on the marine environment, including the elevated risk for hypoxia, which is low levels of oxygen in the water.”
The U.S. House of Representatives recently passed the Long Island Sound Stewardship and Restoration Act, co-sponsored by Rep. Joe Courtney (D-CT-2) and Rep. Nick LaLota (R-NY-1).
The bill authorizes funds, around $40 million, according to LaLota, for preservation efforts through 2028. It’s waiting for a vote in the Senate.
