How to handle water sitting in the pipes of an unoccupied building. By Jessica Kalloch, Director of Business Development, Bill Howe Plumbing, a Gold IREM Industry Partner

This is a just another thing for all of us to think about in these uncharted times. There are many, many
commercial buildings that have been sitting vacant and may continue to stay vacant for a while. When the
day comes that we go back in we should be thinking of some of the potential problems that may arise.
Water sitting stagnant in a pipe for an extended period of time is never a good thing. The possibility of
bacteria growing in that environment is very real. I have seen water lines especially recirculation lines that
have been stagnant for a few years and trust me you would not want that water going anywhere near
anyone. Hopefully none of your building are down long enough for something that bad to happen, but the
start of that process might be taking place as we speak.

Copper piping is somewhat resistant to bacteria and most commercial buildings are supplied with copper
piping so hopefully your piping is mitigating some of this already. The real area of concern would be any
tanks that might be on the property. Water heaters are very capable of growing bacteria. The water temp is
higher which promotes growth to a point and if the glass lining of the tank has been compromised at any
point we would have water sitting with raw steel which will promote growth.
Luckily the water that the City supplies to us is treated to eliminate bacterial growth. If you smell City
water you will notice it is treated with chlorine. Not good for drinking but good for eliminating disease in
our water supply.

Another issue that might come up is the drain system in the building is drying out. Every plumbing fixture
is equipped with a P-Trap and the purpose of the P-Trap is to provide a water seal that prevents sewer gas
from entering the building. As these buildings sit unoccupied the water in these P-Traps is evaporating. If
enough water evaporates the water seal is broken and you could get sewer smells coming into the building.
You might also have some fixtures that will develop leaks or become harder to operate. Don’t be surprised
if you are repairing a few fixtures after this is all over.

The Solution:
Flushing the water lines before you re-open is an easy and very effective way to eliminate any potential
problems. Simply go in and run water from every faucet for several seconds and flush every toilet. You will
get the fixtures back in operating mode again. This will get any of the stagnant water out of the system and
will refill the P-Traps on those fixtures which will eliminate the sewer gas smell problem. The fresh
sanitized water from the city that will now be in the pipes will help eliminate any other potential growth.
You might also consider turning the temperature of any water heaters up for a short time. Bacteria will not
grow in water that is above 140 degrees. Turn the heater up and let it reach a higher temperature to kill
growth. HOWEVER, please remember to turn it back down to the previous setting when you are
done. Skin can be scalded by water at or above 120 degrees SO please turn it back down!!

Jessica Kalloch, Director of Business Developement

Bill Howe Plumbing, a Gold IREM Industry Partner.

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