The following water quality updates have been issued for Wednesday, June 14, 2023:

  • Pet Advisory signage was posted at Schoolhouse Pond, Hyannis due to high estimated Microcystin toxins being present
  • Public Health Advisory signage remains in place at Mystic Lake due to significant Cyanobacteria scum observed

Cyanobacteria Pet Advisory

Pet Advisory Level

Schoolhouse Pond, Hyannis







Public Health Advisory Level

Mystic Lake







If you are interested in receiving more information about Cyanobacteria and locations monitored, you may view the 2023 Cyanobacteria Monitoring Map at

If you are interested in receiving email notifications when there is a potential toxic bloom identified by Association to Preserve Cape Cod (APCC), you may opt-in by clicking this link: where you will be asked to enter your email address in order to receive cyanobacteria alerts.

Thomas A. McKean, RS, CHO
Director of Public Health