FOR IMMEDIATE RELEASE: August 28, 2005
CONTACT: Doc Kokol (850) 245-4111
**HURRICANE KATRINA INFORMATION SHEET **
Department of Health Warns of Risks to
Water Supply Due to Storms
TALLAHASSEE - Hurricanes, especially if accompanied by
a tidal surge or flooding, can contaminate the public
water supply. Drinking contaminated water may cause
illness. Individuals cannot assume that the water in the
hurricane-affected area is safe to drink.
In the area hit by a hurricane, water treatment
plants may not be operating. Even if they are, storm
damage and flooding can contaminate water lines. Listen
for public announcements about the safety of the
municipal water supply.
If your well has been flooded, it needs to be tested
and disinfected after the storm passes and the
floodwaters recede. Questions about testing should be
directed to your local or state health department.
Water for Drinking and Cooking
Safe drinking water
includes bottled, boiled or treated water. Here are some
general rules concerning water for drinking and cooking.
Do not use contaminated water to wash dishes, brush
your teeth, wash and prepare food or make ice.
- If you
use bottled water, know where it came from. Otherwise,
water should be boiled or treated before use. Drink only
bottled, boiled or treated water until your supply is
tested and deemed safe.
- Boiling water kills harmful
bacteria and parasites. Bringing water to a rolling boil
for 1 minute will kill infectious organisms (germs).
Water may be treated with chlorine by mixing eight drops
(1/8 teaspoon; about the size of a dime) of unscented,
ordinary household chlorine bleach (4-6 percent active
ingredients) per gallon of water. Mix the solution
thoroughly, and let stand for about 30 minutes. However,
this treatment will not kill parasitic organisms that
may have entered a flooded well. Iodine tablets
available at sporting goods stores may also be used.
Containers for water should be rinsed with a bleach
solution before reusing them (one tablespoon bleach per
gallon of water). Use water storage tanks and other
types of containers with caution. For example, fire
truck storage tanks as well as previously used cans or
bottles may be contaminated with microbes or chemicals.
Do not rely on untested devices for decontaminating
How do I disinfect my well?
It is important to disinfect both the well and
plumbing with 4-6 percent chlorine, non-scented
household bleach to ensure that all infectious agents
are killed. If you have water treatment devices, remove
all membranes, cartridges and filters and replace them
after the chlorination process is completed.
The amount of chlorine and the length of time you
allow it to remain in your system are equally important.
Common unscented laundry bleach can be used effectively
as a chlorine disinfectant. Follow these steps for the
recommended usage amount of chlorine bleach:
- If the water is discolored before chlorination, run
the water until it is clear for up to 10 minutes.
- Turn off and then drain your hot water
heater—chlorine is not effective in water above 105
- Remove and replace charcoal filters after the
chlorination process is completed.
- To avoid adding contamination to the well during
disinfection, first clean the work area around the top
of the well. Remove grease and mineral deposits from
accessible parts of the well head and flush the outside
surfaces with 1/2 cup of laundry bleach in 5 gallons of
- Turn off the pump. Remove the cap or the well plug
on the rubber seal. There are many types of well caps
and plugs. If you have questions, you should contact a
licensed well driller. If you have a submersible pump,
you may also want to contact a licensed well driller for
advice on disinfection procedures.
Try to coat the sides of the casing as you pour in
one gallon of bleach. If you get chlorine on the pump or
wiring, flush it thoroughly with fresh water to prevent
later corrosion. Your county health department may issue
additional guidance for your area.
- Re-cap or plug the well opening and wait 30
- Turn on and, if needed, reprime the pump. Open all
the faucets on the system one by one. Allow the water to
run until there is a noticeable smell of chlorine. You
may also want to flush the toilets. If you have outside
faucets, you may want to direct the water away from
sensitive plants. If you cannot detect a chlorine odor,
re-chlorinate the well.
- Turn off all the faucets and allow the chlorine to
remain in the system for at least eight hours.
- Backwash water softeners, sand filters and iron
removal filters with chlorinated water.
- Again open all the faucets and run the water until
there is no chlorine smell—for up to 15 minutes.
Is it safe now?
The only way to verify that the water is safe to
drink is to have it tested. Although chlorine bleach is
effective against microorganisms, it will not remove
chemical contamination that may have gotten into your
well. Contact your county health department for sampling
instructions to get your water tested.
For further information, please contact your local
county health department or visit
www.FloridaDisaster.org. Photos of this procedure are on
the USEPA website at:
The Florida Emergency Information Line:
Public Information Emergency Support Function:
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