Public Water Supply

• Safe drinking water must be free of harmful chemicals and disease-producing germs. These germs can cause illnesses such as giardiasis, gastroenteritis, and hepatitis. When there is damage to a well or the well has been flooded, disease causing germs and chemicals can flow into the well water.
• The purpose of disinfection is to kill or inactivate all disease causing germs that may be present.
• Chemical contaminants are more difficult to eliminate. Consult the public health department for advice on dealing with chemical contaminants.

• Laboratory tests can identify specific chemicals and a group of bacteria called "coliform."
• The presence of coliform indicates possible fecal contamination and a potential health hazard.

• Niagara County Dept of Health will test water for the presence of coliform, but does not offer testing for chemicals. There is a charge for the test.
• Private laboratories also test water for coliforms. They will also test for chemical contamination. A listing of these laboratories can be found in the telephone book yellow pages under "laboratories - analytical."

• If coliforms are found in the water, the well can be disinfected as described below.
• Liquid household chlorine bleach is an effective and economical disinfectant. Chlorine bleach is also available in a granule form.

• Improper construction, protection or location of a well is a common cause of well contamination.

In general, wells should be located uphill, a minimum of 100 lineal feet and preferably 200 feet away from any standing water, privy, cesspool, tile field, leaching pit or other sewage disposal system.  Upon receipt of a laboratory report indicating that a well water sample is bacteriology contaminated, all water used for drinking or culinary purposes should first be boiled to maintain a rolling boil for a minimum of two minutes prior to use.  Where a public water supply is available, every effort should be made to use this water supply in preference to any private well water supply.

In the absence of a public water supply, one should try to find and remove the probable cause of pollution.  The cause could be holes in the side of the casing, channels along the length of the casing leading to the well, or crevices in rock connecting surface pollution with the water-bearing strata.  An inspection should be made of the top and inside of the casing, with the aid of a mirror or strong light, to determine if water is entering the well from close to the surface or through the bottom of the casing.  If deficiencies are found, a competent well driller should engaged to investigate the possibility of sealing the opening, installing an inner casing, or installing a new casing carefully sealed in rock with cement grout.

All existing wells used for domestic water supplies which may be subject to contamination should be reconstructed so as to produce safe water, or, if this is not practicable, the well should be abandoned and safe supplies developed by constructing new wells, or water should be obtained from other safe sources.

Dug wells with stone or brick casing should be protected to a minimum depth of 10 feet from existing grade.  In addition, dug wells should have a cover, which is watertight and extends downward at least 2 inches over the wall or curbing of the well with a proper seal.

After the improvements have been completed, the well should be disinfected with an unscented chlorine bleach (blue cap) such as Clorox, Dazzle, 101, etc.  Clorox, Dazzle, 101, and other bleaches containing 6% available chlorine can be purchased in most drug and grocery stores.  Mix two quarts of bleach in 10 gallons of tap water.  Pour the solution into the well while it is being pumped.  Keep pumping the well until chlorine odor appears at all taps.  Close the taps and stop the pump.  It will be necessary to open a valve or plug in the top of the pressure tank if so equipped, in order to permit the concentrated chlorine solution to come into contact with the entire inside of the tank.  After allowing the well to stand idle for 8-24 hours; then air must again be introduced into the pressure tank and the opening closed.  Mix two more quarts of bleach in 10 gallons of water and pour this chlorine solution into the well.  Allow the well to stand idle for at least 8 hours and preferably 12-24 hours.  Pump the well to waste away from grass and shrubbery through the storage tank and taps, until the odor of chlorine disappears.

After all the chlorine is pumped out, a water sample should be collected and tested by the Niagara County Health Department to determine whether all bacteriological contamination has been eliminated.  No water quality sample will be taken if there is any chlorine present.

This procedure is to remove bacteriological contamination in the well casing and/or piping in the house; the disinfection procedure is no assurance that the water entering the well or spring is free of pollution.

CAUTION: Do not use more chlorine bleach than recommended because excessive amounts can be poisonous!

• A disaster such as a flood or an earthquake may contaminate water when sewage systems are damaged or when there are breaks in the water lines.
• Contaminated water can cause many illnesses.
• It is best to have a supply of water on hand to prepare for these times; however, this fact sheet will help you if you did not plan ahead, and you need to find purified water now.

• When it is suspected that water supplies have been contaminated, there will be a public announcement to boil the water. This is known as a "boil water order."
• If there is any chance of your water being contaminated, do not drink it or use it for food preparation or tooth brushing.

• Purified water can be prepared by anyone at home, or it can be purchased. Instructions are provided below on how to purify water at home.
• Canned drinks, such as juices, pop, or beer can be considered purified.
• Boiling water kills bacteria, viruses, and parasites that can cause illness. Treating water with chlorine bleach kills most disease causing bacteria and viruses; however it probably will not kill parasites. Boiling is a more effective water purification method than treating water with chlorine bleach.
• People who have weakened immune systems and who are in an area where the water has been contaminated should always rely on boiling as their home water purification method, or they should buy distilled bottled water or canned drinks.
• Use purified water within six months of its purification or purchase date to assure safety and obtain the best quality.

• Fill a large pot with water after straining the water through a coffee filter or cheesecloth to remove dirt and other particles.
• Bring the water to a rolling boil and keep it boiling for 3 minutes.
• Pour the water into a disinfected drinking water bottle.
• Store in the refrigerator, if possible.

• Containers can be purified either by using bleach as a chemical disinfectant or by boiling the container.
• Plastic containers cannot be boiled.
• Before using either method provided  to disinfect a container, wash the container thoroughly with soap and water, and rinse out the container with water.

The container should be disinfected with unscented chlorine bleach (blue cap) that contains 6% available chlorine such as Clorox, Dazzle, 101, etc., which can be purchased in most drug and grocery stores. If household bleach is utilized as a disinfecting agent, a concentration of 200 mg/l or parts per million (ppm) available chlorine is required to provide effective disinfection.

A 200-ppm available chlorine solution can be produced by adding two (2) ounces of household bleach (6%) to five gallons of tap water.  Please note that not all surfaces and materials are compatible with a bleach solution.  The department recommends that you test an inconspicuous area for compatibility prior to use.

All safety precautions outlined on the bleach bottle should be followed when handling any chlorine solution.    

The bleach solution must completely fill the container and remain in contact with the inside of the container for a minimum of 30 minutes.  The disinfected water must be discharged to waste away from any existing surface water bodies, streams or valuable vegetation.  The cooler should be rinsed thoroughly with a clean source of water and filled accordingly.

The bleach/water ratio for different size containers is as follows:

• For a 5 Gallon container of water -  add 2 oz. of 6% bleach
• For a 10 Gallon container of water -  add 4 oz. of 6% bleach
• For a 20 Gallon container of water - add 8 oz. of 6% bleach
• For a 30 Gallon container of water -  add 12 oz. of 6% bleach

• You may boil glass bottles or jars to disinfect them.
• In a large pan submerge the glass bottle or jar in water.
• Bring to a rolling boil and then boil the container for 10 minutes.
• Fill the glass bottles and jars with purified water and cap the container for later use.
• Use the stored water within six months.

• Use clean plastic or glass containers such as soft drink bottles or canning jars that have tight fitting screw caps.
• Do not use milk bottles - they do not seal well.
• Water containers should be disinfected before filling them with purified water the first time and disinfected again each time they are refilled.