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Lopez Lake
Lopez Lake

Conversion of Drinking Water Disinfectant to Free Chlorine for the Five-Cities Area

Author: Public Works
Date: 10/23/2020 10:56:05 AM

The County of San Luis Obispo Department of Public Works will change the disinfectant to free chlorine in the Lopez Project water distribution system from October 28, 2020, through November 19, 2020.

Because the County provides water to the cities of Arroyo Grande, Pismo Beach, Grover Beach, Oceano, Avila Beach, and Port San Luis, these areas may also be converting to free chlorine. 

Free chlorine is a stronger disinfection process than the blended chlorine treatment typically used by the County. This annual switchover of disinfectants helps to ensure water mains remain free of potentially harmful bacteria. This is considered a best management practice in the water industry.

Each individual customer has their own sensitivity level to the taste and/or odor of chlorine. Although many detect no change at all, others may notice a taste or chemical odor similar to a swimming pool. Free chlorine can be minimized or removed by boiling water, running water through a carbon filter, or filling a container with water and leaving it to vent overnight.

Chlorination is the most common disinfection practice used in the drinking water industry.  Most customers will not need to take any precautions as the water remains safe to drink by Federal and State drinking water standards. If you have any questions or concerns about your drinking water, please contact your local water supplier.