Save The River’s Beach Watch Water Quality program tests the waters of nine popular swimming locations on the Upper St. Lawrence River. Water Quality is determined by the number of E. coli colonies per 100 milliliter (mL) sample. If a sample has a concentration of over 235 colonies, it is considered unhealthy for humans by the New York State Health Department.
All nine locations tested by Save The River volunteers and staff came back within safe levels of E. coli for swimming. The highest was about 162 colonies in the 100mL sample at the Cove, Thousand Island Park. Scenic View Park, Alexandria Bay, came back at just over 115 colonies. Other sites include Wilson’s Beach, Cape Vincent; Potters Beach, Grindstone; Round Island, Clayton; Sawmill Bay, Clayton; Bathtub Bay, Picton Island; the Lake of the Isles, Wellesley Island; Frink Park, Clayton.
With the 2025 Beach Watch season coming to a close, overall water quality across most locations was good with the majority of sites well below safe standards of E. coli. Occasional short term upticks in coliform count were observed, but did not persist. The one exception to this was Sawmill Bay, Clayton, which reached a high count of 1,732.9 on July 14. This was the only site to repeatedly fail to meet health standards and highlights the need for continued monitoring and testing.
Save The River would like to extend a sincere thank you to all the volunteers who make the Beach Watch program possible. Each week, their commitment and consistency in collecting water samples and delivering them to our office have been vital in protecting the River we all love.
When a site fails, Save The River notifies the affected municipality or homeowners association. Beach Watch volunteers and Save The River do not have the authority to close beaches or swimming areas. The results are used to inform any possible stakeholders of potential health risks associated with water quality and to inform local and state authorities if a location fails.
For the last 26 years, Save The River has sampled popular swimming locations every week throughout the summer. This year they will test every week from July 7 to August 27. The results of each test are posted on Save The Rivers website at www.savetheriver.org, Save The River social media, the Save The River storefront located at 409 Riverside Drive, and on the Swim Guide mobile app and website at theswimguide.org.
1. Wilson’s Beach
2. Sawmill Bay
3. Potters Beach
4. Frink Park
5. Picton Island
6. Round Island
7. The T. I. Park Cove
8. The Lake of the Isles
9. Scenic View Park