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Floods are one of the most common hazards in the U.S. While most people don't believe that they could be impacted by flooding, floods impact New Hampshire annually and are likely to occur in many jurisdictions.

photo of car in flooded road

Not all floods are alike. Some floods develop slowly – often times over a period of days. Flash floods can develop quickly, sometimes in a matter of minutes and without any visible signs of rain. Flash floods often have a dangerous wall of roaring water that carries rocks, mud and other debris, sweeping away most things in its path.

Take Action Before a Flood

Before an event, information about the risk of floods can be found on local television and radio, the National Weather Service, and NOAA. To find out about any potential flooding in your area, visit and input your zip code.

Steps to Be Ready

  1. Complete the Family Emergency Plan pdf file and discuss it as a family. This is a simple way of keeping each member of the family informed on critical information: where to reconnect should you become separated, who to call, and what you will do should a flood occur.
  2. Complete the Emergency Contacts Card pdf file for each family member.
  3. Develop an Emergency Kit. Your Emergency Kit should be easily accessible if you have to leave your home in a hurry, and should account for the needs of each family. Make sure it is ready to go at all times of the year and contains items suitable for the season.

Take Action to Evacuate or Shelter-in-Place

Floods are one of the emergencies that may require you to evacuate your home. You will need to stay tuned to local information so that you know if you need to evacuate. There are some actions you can take today to get prepared so that you will know what to do if you stay at home or if you need to leave. A simple action to take is to elevate important documents and appliances in your home to keep those items safe from flood damage. Additional steps you can take include:

  • Find out if you live in a flood-prone area.
  • Know if your property is above or below the flood stage water level and learn about the history of flooding for your region.
  • Ask your insurance agent about flood insurance. Most homeowner and renter policies do not cover flood damage, but can be accessed through the National Flood Insurance Program (NFIP).
  • Have check valves installed in building sewer traps to prevent flood waters from backing up in sewer drains.
  • Seal walls in basements with waterproofing compounds to avoid seepage.

Be Safe During Floods

During a flood it is important to be aware and knowledgeable on what is happening. Listen to news reports, secure important items to higher ground and get ready to make the decision to stay or go. If you are advised to evacuate, do so immediately. Evacuation is simple and safer before the flood waters rise. Don't forget your Emergency Kit, which should include your Emergency Contacts Card, and your Family Emergency Plan pdf file which includes your evacuation location options. Have your evacuation plan ready, and follow recommended routes. Know that flash flooding can occur. If there is any possibility of a flash flood, move to higher ground right away. Do not wait for instructions to move.

If you leave your house, remember:

  • Turn Around, Don't Drown! ®
  • Avoid walking or driving through flood waters.
  • Just 6 inches of moving water can knock you down, and 1 foot of water can sweep your vehicle away.
  • Use a stick to check the firmness of the ground in front of you.
  • Listen to the radio or television for information.

Make Your Home Safe

  • If you must evacuate, secure your home. If you have time, bring in outdoor furniture. Move essential items to an upper floor to protect them from flood damage.
  • If instructed, turn off your gas and electricity at the main switch or valve to help prevent fires and explosions.
  • Disconnect electrical appliances. Do not touch electrical equipment if you are wet or standing in water.

Be Safe in a Vehicle

  • Do not drive into flooded areas.
  • If floodwaters rise around your car but the water is not moving, abandon the car and move to higher ground. Do not leave the car and enter moving water.
  • Know that 6 inches of water will reach the bottom of most passenger cars causing loss of control and possible stalling.
  • Be aware that most vehicles begin to float in just 12 inches of water. 24 inches of water will sweep most vehicles away, including SUVs and pick-ups.
  • Avoid camping or parking along streams, rivers, and creeks during heavy rainfall. These areas can flood quickly with little warning.

Take Action After a Flood

Many injuries take place after a flood happens. Flood waters, standing water and flood water residue pose various risks including injuries, infectious diseases and chemical hazards. Steps that you should follow after a flood include:

  • Return home only when authorities say it is safe.
  • Stay away from power lines and electrical wires. Electrical current can travel through water. Report downed power lines to the power company.
  • Don't use appliances or motors that have gotten wet unless they have been taken apart, cleaned, and dried. Some appliances, such as television sets, keep electrical charges even after they have been unplugged.
  • Wait before entering a structure damaged by flooding. Structures that have been damaged by flooding may not be safe to enter. Wait for the building to be inspected before entering.
  • Be alert for gas leaks. Use a flashlight to inspect for damage. Don't smoke or use candles, lanterns, or open flames unless you know the gas has been turned off and the area has been ventilated.
  • Listen for news reports to learn whether the community's water supply is safe to drink.
  • Photograph damage to your property for insurance purposes.

Avoid Floodwaters

Water may be contaminated by oil, gasoline, or raw sewage. Water may also be electrically charged from underground or downed power lines.

  • Service damaged septic tanks, cesspools, pits, and leaching systems as soon as possible. Damaged sewage systems are serious health hazards.
  • Clean and disinfect everything that got wet. Mud left from floodwater can contain sewage and chemicals. You can use a solution of 1 cup of bleach to 5 gallons of water to disinfect surfaces, especially those that may come into contact with food or areas where small children play.
  • Look out for any mold growth after a flood and learn about the best way to address any issues that you see.

Flood Key Terms
Flood Watch
Conditions are right for flooding to occur in your area.
Flash Flood Watch
Flash flooding is possible. Be prepared to move to higher ground.
Flood Warning
Flooding is occurring or will occur soon; if advised to evacuate, do so immediately.
Flash Flood Warning
A flash flood is occurring; seek higher ground on food immediately.

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