The City of Moncton has expanded its water ban on recreational activities to include Jones Lake and Centennial Park pond.
Officials say the water is being tested for the presence of blue-green algae.
The waterways have been closed as a precautionary measure.
Kayaking and canoeing are not permitted and pet owners are urged to keep dogs away from the water.
Irishtown Nature Park was closed last week for recreation due to blue-green algae.