The New London Day 10/10/2024
By Kimberly Drelich
Day Staff Writer
Groton ― The eastern part of Long Island Sound has received a top grade for water quality, while Mystic Harbor and outer Stonington Harbor ranked among the top five bays in the state, with Wequetequock Cove in Stonington among the worst.
These were among the results of a report card grading the ecological health of Long Island Sound and its 57 bays and harbors.
Save the Sound, a nonprofit organization focused on the restoration of Long Island Sound and surrounding lands, released its 2024 Long Island Sound Report Card during a press conference Thursday outside the Project Oceanology building at the University of Connecticut-Avery Point.
While Long Island Sound’s water quality has improved over the years, more work remains to reduce nitrogen levels and help the surrounding bays and harbors, said Peter Linderoth, the director of water quality for Save the Sound.
Jason Krumholz, associate professor at the University of Connecticut and stewardship coordinator for the Connecticut National Estuarine Research Reserve, said 98% of the open waters of Long Island Sound now score a B or better, based on amounts of chlorophyll, dissolved oxygen and seaweed along with water clarity and oxygen saturation levels.
The Eastern Basin of the sound, where water quality has been steady over the years, received an A+ grade. Krumholz said the region has a much lower coastal population, lots of undeveloped land and strong tidal exchanges with the Atlantic Ocean.
The rest of the sound received grades, ranging from an A in the Central Basin, to an F in the Western Narrows, near densely populated New York City. But Krumholz said New York City has invested in nitrogen pollution reduction at its sewage treatment plants, and there is some moderate improvement.
He added that Long Island Sound has seen improvements over the past 16 years, but climate change, continued population growth and development have threatened to undo some of this work. He said rising water temperatures have a range of potentially damaging impacts on the marine environment.
Krumholz also said 42% of the bays and harbors around the sound are still getting a discouraging grade of a C, D or F, and local action is critical to protect them.
Linderoth said the bays in eastern Connecticut generally are surrounded by on-site septic systems and cesspools that really don’t remove nitrogen before that wastewater makes its way into the groundwater. He said that tends to be a leading stressor on the bays, as well as fertilizer use and stormwater runoff.
Grades for local waterways
Wequetequock Cove, Stonington: D-
Mystic River: C-
Mystic Harbor: A-
Inner Stonington Harbor: B+
Outer Stonington Harbor: A
Alewife Cove, Waterford/New London: B
Mumford Cove, Groton: A-
Poquonnock River, Groton: B
Inner Niantic River: C+
Outer Niantic River: A-
Connecticut River: A-
How to help
State Sen. Heather Somers, R-Groton, said in remarks read aloud Thursday that the report card brings promising news for the region as water quality in the Sound continues to improve, but also underscores the significant challenges that remain, particularly in bays and areas near urban centers.
She said many bays continue to face elevated levels of nitrogen from stormwater runoff, fertilizers and aging septic systems, and southeastern Connecticut “must continue investing in wastewater infrastructure improvements to protect these local waterways.”
Project Oceanology was among the organizations that collected water data for the bays. It’s executive director, Andrew Ely, said the work gives its staff and educators the opportunity to participate in science that they can then bring into the classroom and reach the next generation of policymakers, engineers, scientists and global citizens.
Linderoth encouraged people to take steps to help the Sound. These include reducing water use; maintaining and upgrading sewers, septic systems and cesspools; reducing their carbon footprint by taking public transportation, walking or biking, shopping local and using energy-efficient appliances; planting native plants; eliminating or reducing fertilizer use; and making their voice heard about the importance of clean water.