Greenwich swimmers have mostly clean waters this summer — but one beach continues to struggle after storms.

Three of the town’s four public beaches earned A or A+ ratings in Save the Sound’s latest water quality report based on 2025 testing data. Greenwich Point and Great Captain Island received A+ grades, while Island Beach earned an A.

Byram Park Beach received a D+, failing water quality tests 36% of the time overall and 56% after wet weather.

Town officials say Byram’s location makes it more vulnerable to pollution from stormwater runoff. The beach sits in an inlet with limited tidal flushing, and nearby drainage systems and a brook can carry runoff into the water.

“The beach is closed when the area gets 0.3 inches or more of rain,” said Michael Long, Greenwich’s director of environmental services.

The latest grade is an improvement from recent years, when Byram received an F in 2023 and a D- in 2024.

Greenwich tests all four beaches weekly through its own laboratory and increases monitoring when bacteria levels rise. The town has also invested more than $70 million in shoreline sewer and collection upgrades over the past decade.

Residents can check daily swimming conditions on the city's website. Officials advise avoiding swimming after significant rainfall, especially at Byram Beach.