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Water contamination is one major health hazard after a devastating hurricane. If water is tainted by bacteria, it can cause severe diarrhea which can be life threatening if untreated.

Tune in for instructions

Listen carefully to instructions from local authorities as the local water supply system is vulnerable to contamination during a storm when water pressure is lost; flooding can also allow sewage to enter the water supply system. The Water Authority will issue updates on the state of the water supply; until the all clear is given to do otherwise, it is wise to boil all water before use.

Disinfecting water by boiling

  • Let the water get to a “rolling” boil for at least 2 to 3 minutes.
  • Let it cool and add a pinch of salt.
  • Pour the water back and forth between clean containers to reduce the flat taste.

Water that has been saved in bottles before a storm should be good for up to six months, if properly stored. When filling bottles, leave no air in the container, and put filled containers in a cool, dark place. When in doubt as to the quality of the water stored, disinfect before use.

Disinfecting water using purification tablets or bleach :

To ensure safe, clean water, use water purification tablets and water filters. Purification tablets contain iodine, halazone, or chlorine which kill most waterborne bacteria, viruses, and parasites. But some parasites such as Cryptosporidium parvum, Giardia lamblia, and larger bacteria are not killed by purification tablets, so also use a water filter. Filters must be 1 micron absolute or smaller. Over time, purification tablets lose their potency, so maintain a fresh supply. Water sanitizing tablets for washing dishes can also be purchased (but don’t confuse the two).

Using chlorine tablets specifically labeled for drinking water (NOT POOL TABLETS)

  • Follow package directions.
  • The general rule is one tablet to each quart of water.
  • Ensure tablets dissolve completely by mixing thoroughly with water.
  • Let sit for 30 minutes.
  • Note that iodine should not be used by persons with iodine allergy, with active thyroid disease, or by pregnant women.

Using household bleach

Normal household bleach also kills most water germs. Read the label before buying and use only standard household bleach (5% chlorine) with no extra whiteners, brighteners, or scents. If the only active ingredient in the bleach is Sodium Hypochlorite , it is suitable for water sterilization.

  • Add ½ tsp. to five gallons of clear water or one tsp to five gallons if water is cloudy.
  • Allow water to sit at least 30 minutes. Stir or shake the water to assist with mixing. This sitting time is an important part of the process. Use clean sterile utensils to mix.
  • If the water lacks a slight chlorine odour after treatment, repeat process and let sit for another 15 minutes.
  • If you want to pre-filter the water, stock up on large coffee filters, and pour water through them before adding the bleach.
  • Bleach deteriorates on storage so be sure to rotate your supply and have a fresh stock. Also, store well – not in direct sunlight.

Using liquid iodine

  • Contact the Department.

Safeguards against contamination:

  • Use disinfected water to brush your teeth and to give pets.
  • Wash your hands frequently with disinfected water and soap or with hand sanitizers.
  • Use water stored in the bathtub or from the pool to flush the toilet.
  • Avoid drinking or cooking with pool water.
  • Bathing with poor quality tap water is fine, avoid contact with eyes, ears, or mouth. When shaving with tap water, treat cuts with antiseptic.
  • To clean contact lenses use bottled water only. Wash hands carefully before handling lenses.
  • Don’t drink water from wells, especially in areas of sewage contamination.
  • Disinfect tap water used for cooking, drinking or washing dishes if doubtful of water quality.
  • Always use clean containers for water.