It was reported in the news recently that a woman died after a waterborne illness that she received from her dentist (view article). The illness was from the Legionella virus. What most people don't know is that Legionella is in everyone's water in small amounts. The reason this person was infected and died was most likely due to the fact that the pump in her dental chair had not been maintained properly, therefore causing the Legionella virus to grow out of control.

Although Legionella is in everyone's water in small amounts, it does not typically become dangerous until it has been allowed to populate, or grow. One way Legionella can multiply is in your water heater. The warm water below 140 degrees is the perfect breeding ground for the Legionella. One solution is to turn the temperature on the water heater over 140 degrees and install a mixing valve to return the water temperature on the out going side to 120 degrees. The additional benefit to this higher stored water temperature is that you actually increase the volume of delivered 120 degree water by as much as 40%. WARNING: never allow water over 120 degrees to be distributed to your faucets. If you have never had your plumbing inspected, you might also want a professional to make sure that you do not have any “dead ends” in your water piping system. A dead-end is another area that can harbor Legionella and other harmful waterborne contaminants. The technical or code definition of a dead-end is a pipe that is more than 2 feet in length and does not feed anything. A common dead-end in a home could be a water pipe that used to feed a fixture or a hose faucet and is no longer being used. The water will literally stagnate in that pipe, and any negative pressure will wash all of those contaminants into the water that you drink and shower in.

In case you are thinking that you are safe because you don't drink your tap water, please be careful. Legionella and many other contaminants find their way into your body not from ingesting them, but rather when you inhale them from the mist of your shower. Every confirmed case of Legionella poisoning has been a result of it being airborne. To learn more about how to keep your family safe or to set up your own home inspection, just call the offices of John Baethke & Son Plumbing in Chicago at 773-276-5430, or email me at