The New Hampshire Department of Environmental Services encourages residents to take precautions during and after the flooding, including protecting their drinking water. Flooding can cause the contamination of water with fecal matter from sewage systems, septic tanks, as well as contamination from oil, gasoline and other chemicals.
If you are on a public water system, check "Drinking Water Advisory" under ALERTS on http://des.nh.gov to see if your system is under a boil order. If it is, please read the information below to ensure your water is safe to drink.
After a flood, private drinking water wells may have been contaminated by the floodwaters. Heavy precipitation tends to mobilize bacteria and thus highlight conditions of poor well construction. DES urges all private well owners who’s well has been flooded to boil their water for drinking and to have their well water quality tested after the floodwaters have receded.
How to make sure your drinking water is safe:
- Disinfect and test flooded private water wells after floodwaters recede.
- To request a test container from the DES Laboratory, please contact 271-3445.
- For information on disinfection of private wells, please go to Disinfecting A Private Well
(DES Fact Sheet). - Chlorinating a Well and Water System - Montana State University video (9:27 min)
- For information on proper construction of private wells, please go to
Bedrock (Artesian, Drilled) Well Design
– for bedrock (artesian, drilled) wells (DES Fact Sheet)
Dug Well Design
– for dug wells (DES Fact Sheet)
Point Well Design
– for point wells (DES Fact Sheet).
- Safe water for drinking, cooking, and personal hygiene includes bottled, boiled, or treated water. Do not use contaminated water to wash dishes, brush your teeth, wash and prepare food, wash hands, or make baby formula.
- If you use bottled water, be sure it came from a safe source. If you do not know that the water is from a safe source, you should boil or treat it before you use it.
Additional safety tips during and after flooding:
- Be aware of potential chemical hazards you may encounter during flood recovery. Floodwaters may have moved containers of solvents, petroleum, or other hazardous chemicals from their normal storage places. If any propane tanks (whether 20-pound tanks from a gas grill or household propane tank) are discovered, do not attempt to move them yourself. These represent a very real danger of fire or explosion and if found, police or fire departments should be contacted immediately. To report a hazardous materials/waste spill, call 271-3899; to report a petroleum spill, call (603) 271-3644; after hours call (603) 223-4381.
- Car batteries, even those in floodwater, may still contain an electrical charge and should be removed with extreme caution by using insulated gloves. Avoid coming in contact with any acid that may have spilled from a damaged car battery.
- Dams are at or near flood levels. If you should observe any areas of erosion or instability around a dam, report it immediately to 271-3406 or after hours at 1-800-852-3411.
- Do not allow children to play in floodwaters, and do not allow them to play with toys that have been in floodwater until the toys have been disinfected. For disinfection, use 1/4 cup of bleach to one gallon of water.
For more information about environmental impacts from floodwaters, please contact the NH Department of Environmental Services at (603) 271-3503 or www.des.nh.gov. For public health information, please contact your local health department or the Division of Public Health Services at (603) 271-4496.
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