Report shows steady improvement in Long Island Sound water quality

A recent report from the nonprofit organization Save the Sound indicates that billions of dollars invested in wastewater treatment and other infrastructure improvements in Connecticut and New York have led to steady advancements in the water quality of Long Island Sound. The report, published every two years, assesses the sound's health by dividing it into five segments and numerous smaller bodies of water.

Notably, the three main basin segments all received "A" grades based on water samples taken in 2025, while the eastern narrows received a "B" grade for the second straight year. However, the eastern narrows and the smallest area around New York City, which previously had an "F" grade, have improved from a "F" to a "D." While officials credit these investments in upgrading wastewater systems for the improvements, they also acknowledge ongoing challenges from climate change, coastal development, and occasional stormwater and sewer overflows.

Despite this, Peter Linderoth, Director of Healthy Waters and Lands at Save the Sound, remains optimistic about the future. The report's findings were unveiled at a press conference in Darien, Connecticut, and officials attribute the progress to state and federal investments, with Connecticut spending approximately $1.2 billion over the past two decades to address combined sewer overflows.