On July 28, 2026 the APCC reported that potentially toxic cyanobacteria blooms have recently been detected in Santuit Pond, Mashpee, and North Pond, Barnstable. See 8/25/26 update below.

The town has been notified of the findings. If you have any questions, contact the local health department.

You can view the most recent sampling date and results on the APCC's interactive map.

Avoid contact, particularly incidental ingestion of pond water that can occur during swimming. Dogs and children are especially susceptible to cyanotoxins through ingestion.

Frequently asked questions about cyanobacteria, click here.

If you see a possible bloom in a pond, avoid it and notify your local board of health. Take a picture, note the location and date and send to cyano@apcc.org.

8/26/26 update: Today I spoke with Rick York, retired Mashpee Director of Natural Resources. Rick is currently sampling and analyzing the water in Mashpee's ponds. He said that the pond is holding up well so far compared to previous years, which explains why to the town hasn't issued a warning about the pond after the APCC report on July 28th. Although there is some cloudiness from algae, he though the pond looked more brown than green, which is a sign of more benign algae. He also observed that the overall clarity is much better. Last year you couldn't see 6" down into the water, and now you can see the bottom pretty clearly at a couple of feet. There are reasons to be hopeful about this, and I'll go into that later. -JG