City of San Angelo to Temporarily Change Water Disinfection Method

SAN ANGELO, TX — The City of San Angelo Water Utilities Department will change how it disinfects the public water supply from May 30 to June 30. 

This annual preventive maintenance helps maintain the water distribution system, according to a press release from the City.

Water users may note a slight change in the smell, taste and appearance of their water that should subside after a couple of weeks. This may include a chlorine odor and minor discoloration. The water will remain safe for all normal uses, the release stated.

Chlorine levels and water-quality standards in the distribution system will be monitored daily to ensure all regulatory standards are met.

The Water Utilities Department normally uses chloramine, a mix of ammonia and chlorine, to disinfect water. From May 30 to June 30, the department will use only chlorine, also known as free chlorine, which is a stronger disinfectant than chloramine. This is an annual practice common for municipal water systems. 

Frequently Asked Questions

Will this change require any action on my part? No. Residents may continue to use and drink water as normal. 

What changes to the water quality will I notice during this period? You may notice a stronger chlorine taste and smell, especially in showers and sinks. Water may also appear slightly discolored in areas with low water flow. These symptoms should fade within a couple of weeks.

How can I reduce the chlorine taste and smell? A carbon filter can help remove the taste and odor of free chlorine and chloramines. If you have an existing carbon filter on your faucet, reverse-osmosis system or cartridge under the sink, it should continue to work effectively. These are available at local retail stores and are typically easy to install.

I have a fish tank. How will it affect my fish? No change or adjustment is typically needed because the same process you have in place to remove chloramines should also remove free chlorine. Check with your equipment supplier to be sure.

Will this affect my RO system? Some reverse osmosis systems are not designed to work with water that has free chlorine. Check with your system manual or manufacturer to determine if any changes are needed.

I’ve heard this can affect kidney dialysis machines. Is this true? We recommend you check with your equipment supplier, as different equipment may have different needs or adjustments. The City has contacted local hospitals to alert them of the change.

Will the City take steps to reduce the elevated odor and taste? The City will implement procedures to reduce effects as much as possible. Free chlorine levels will be monitored daily and fire hydrants in low-flow areas may be flushed to keep water moving through the system.

Can free chlorine bleach my clothes? Free chlorine is a stronger disinfectant than chloramine, but its residuals in the system will be lower. Bleaching is not expected, but to protect new, unwashed clothing, consider washing them in cold water first to help set the colors.

Will my water quality improve after this? After switching back to chloramine, the system typically requires less disinfectant to maintain proper levels. Those sensitive to chloramine may notice improved taste and smell.

Why is the City making this change? This temporary switch from chloramine to free chlorine is standard preventive maintenance. Free chlorine is more effective at controlling microbial buildup inside pipes. Many U.S. water systems using chloramine periodically make this switch to maintain system cleanliness and performance.