Why isn’t chlorine treatment of potable water enough to keep water safe?

I had some water utility workers ask me, “Why isn’t chlorine treatment of potable water enough to keep water safe? Why should we worry about cleaning tanks when we already use chlorine?”

Chlorine works great as long as there is not a breach in the tank. When there is a breach like a hole in the top that lets birds and insects inside the tank, the chlorine can not keep up. This is why annual tank inspections are so important. People have died from this scenario, see: “Salmonella Outbreak in Alamosa, Colorado“. According to USEPA officials a sediment build up on the interior floor of a water storage tank is another type of breach. Bacteria like Legionella, protozoa like Cryptosporidium, and a wide range of viruses including Norovirus can hide and GROW in the tank sediment.

Do you know what the #1 cause of municipal water contamination is? According to the CDC it is a microscopic parasite called Giardia. The sediment becomes a perfect habitat providing both shelter and food for Giardia and many other microorganisms to grow. In time, the contaminants can reach a point where they overwhelm chlorine or any other disinfectant you may be using. Keeping tanks clean keeps your drinking water safe.

Giardia- Photo CDC website

Top 10 Causes – Outbreaks in Public Water Systems*

• Giardia
• Legionella
• Norovirus
• Shigella
• Campylobacter
• Copper
• Salmonella
• Hepatitis A
• Cryptosporidium
• E. coli, excess fluoride (tie)

For a complete listing of water-related surveillance data, see CDC’s Surveillance Reports for Drinking Water-associated Disease & Outbreaks.

A professional potable water Dive Crew can remove tank sediment along with everything that is growing in it with minimal water loss.  The diver is sealed in a DRY suit so there is no human contact with the water supply.  Before entering the water system the diver is washed down with a chlorine solution to meet state and federal guidelines. The diver can then enter the tank and make quick work of removing tank sediment and any contaminant that may be hiding in it. It is basic housekeeping! You would not drink out of a dirty glass, no one should drink out of a dirty water storage tank or tower either. If you need a water storage tank or tower cleaned, give us a call toll free at 1-888-481-1768 for a free quote.

For more information on Municipal Water Tank Cleaning see: Ron Perrin Water Technologies web Site: www.rpwt.us.

Content source: Centers for Disease Control and Prevention, National Center for Emerging and Zoonotic Infectious Diseases

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