August 2013, the death of a 4-year-old boy staying near Violet, Louisiana, was linked to the naegleria fowleri amoeba. The child had been playing on a slip and slide connected to the St. Bernard Parish’s water system that was later found to be contaminated with the amoeba.
More common in Australia NBC news reported that this was the first case in the U.S.
Keeping the city’s potable water storage tanks and towers clean may be more important now than ever!
Over time almost all tanks accumulate sediment on the floor. Any amount of sediment can become a habitat for bacteria, protozoa (like Cryptosporidium) and viruses. However, when tests show chlorine depletion, the idea of removing the sediment is usually not thought of. Additional treatment chemicals are usually the first line of defense, quickly becoming chemical warfare and potentially leaving the tank with low, or no, chlorine protection for long periods. American Water Works Association (AWWA) recommends that potable water storage tanks be cleaned every 3 to five years. Few states actually require tanks to be cleaned on a regular basis, and some don’t require it at all.
When a contaminant (bacteria, protozoa or viruses) enters a water storage tank and finds sediment to get a foothold in, chlorine can be quickly depleted while the contaminants grow under the protection of the sediment. Even otherwise harmless bacteria can help to deplete chlorine reserves leaving the tank vulnerable to more dangerous contaminants.
Removing sediment from the floor of potable water storage tanks greatly reduces the chance that any contaminant can get a foothold in the distribution system and grow to become a larger problem.
So why isn’t cleaning potable water storage tanks a common practice? Removing tanks from service to perform cleaning is time consuming and expensive. The smaller the water utility, the more difficult it is to find the budget for preventive maintenance. There are many contractors that offer Potable Water Dive crews that can remove floor sediment with little or no down time and minimal water loss. Using a qualified potable water dive crew to clean water storage tanks can save the water utility time and water.
Keeping potable water storage tanks free of accumulated sediment is essential for the health of the system and the health of your customers. If you administer a drinking water system, make a plan to schedule cleanings and stick to it.
For more information on Potable Water Divers see: www.ronperrin.com
For more information on Naegleria fowleri amoeba in drinking water see:
NOTE: You cannot be infected with Naegleria fowleri by drinking contaminated water. In very rare instances, Naegleria infections may also occur when contaminated water from other sources (such as inadequately chlorinated swimming pool water or contaminated tap water) enters the nose. (For example: when people submerge their heads or cleanse their noses during religious practices, and when people irrigate their sinuses (nose) using contaminated tap water.)