Rhode Island Department of Environmental Management

07/23/2025 | Press release | Distributed by Public on 07/23/2025 10:48

RIDOH and DEM Lift Advisory at Slack Reservoir

RIDOH and DEM Lift Advisory at Slack Reservoir

Published on Wednesday, July 23, 2025

The Rhode Island Department of Health (RIDOH) and Rhode Island Department of Environmental Management (DEM) have lifted the recommendation to avoid recreational activities at Slack Reservoir in Smithfield/Johnston. The harmful algae bloom (HAB) caused by blue-green algae (cyanobacteria) has cleared. Recent testing shows algae levels are low and no toxins were detected, meeting safety guidelines.

HAB conditions can change quickly, and blooms may affect Slack Reservoir again, or other areas in Rhode Island. Water with HABs may be bright to dark green with thick, floating algal mats. The water may look like green paint, thick pea soup, or green cottage cheese. If you see water like this, keep people and pets away from it. Toxins may persist in the water after a blue-green algae bloom is no longer visible.

To report suspected blue-green algae blooms, contact DEM's Office of Water Resources at 401-222-4700 Press 6 or [email protected] and if possible, send a photograph of the reported algae bloom. For more information and the Cyanobacteria Tracker Dashboard that lists current advisories and data, visit: https://www.dem.ri.gov/bluegreen

Rhode Island Department of Environmental Management published this content on July 23, 2025, and is solely responsible for the information contained herein. Distributed via Public Technologies (PUBT), unedited and unaltered, on July 23, 2025 at 16:48 UTC. If you believe the information included in the content is inaccurate or outdated and requires editing or removal, please contact us at [email protected]