Toxic algae returns to upper reservoir

City of Norwalk water plant personnel have detected a harmful algae bloom in Upper Reservoir. Some of the algae has overflowed into Memorial Reservoir.Therefore, a Do Not Contact advisory has been issued for both Upper and Memorial reservoirs.Lower Reservoir has been isolated from Memorial and Upper reservoirs. The city's drinking water is produced from water in Lower Reservoir. The drinking water is unaffected by the harmful algae bloom.Testing has confirmed there are no algal toxins in Lower Reservoir or the drinking water.Algal toxins have been confirmed in much of Upper Reservoir and the area of Memorial Reservoir nearest the spillway from Upper. The no-contact advisory includes all of Memorial Reservoir as a precaution because the toxins may spread depending on the water flow from Upper and the wind direction. Humans and pets should not have any contact with the water in Upper and Memorial reservoirs. Most importantly, pets should not be allowed to drink from Upper or Memorial reservoirs.Both Upper Reservoir and the appropriate portion of Memorial Reservoir have been treated with copper to kill the harmful algae. As the algae dies, the toxins will dissipate. The Do Not Contact advisory will remain in effect until toxin levels return to an acceptable level. At that time, the public will be informed. Updates will be posted on the City of Norwalk Facebook page. People with questions may call the water plant at 419/663-6725.