Floods occur frequently throughout the United States, but they typically differ in intensity by region. Floods often form slowly, but flash floods form in minutes, typically without warning. Some floods only affect a small community, while others have devastating consequences throughout entire states or river basins.
Flash floods form very quickly following heavy rainfall, levee or damn breakage, or rapid ice melt. Flash floods typically carry debris, large chucks of mud, and heavy rocks. Overland flooding occurs after heavy rain or rapid snowmelt causes river or stream water overflow. These are the most frequently occurring types of flooding. During overland flooding, drainage systems are typically unable to effectively divert water to outlets.
Floods can occur anywhere, especially in basins or valleys below large water sources, cities below sea-level, or areas near large damns or levees. Floods can even occur near small creeks, rivers, streams, and other low-lying areas not designed to divert water flow.
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What to Do Before a Flood
Flooding can occur almost anywhere, but you can take steps to limit flood hazards.
Regardless of how protected your community is from flooding, it can flood anywhere with rain or snowfall. Even if it has never flooded in your community, it does not mean it is immune from flooding. Flood risk is affected by topography, rainfall, new development and construction, and erosion.
Flood-hazard maps are available to illustrate local flood risk. These maps are used by insurance companies to calculate flood insurance premiums. Homeowners insurance does not cover flood-related damage.
In addition to purchasing flood insurance, these tips will prepare you for potential flooding:
- Develop a family communications plan and amass an emergency preparedness kit.
- Do not build a home below a floodplain unless you intend to reinforce and elevate your house.
- If you live in a region with a history of flooding, elevate electric boxes, water heaters, and furnaces.
- Place “check valves” in your home to reduce flood water drainage in home drains.
- If possible, build barriers to prevent floodwater from entering your home and seal basement walls with waterproofing compounds.
Driving: Flood Facts
While driving, these signs indicate potential flooding:
- Water six inches deep reaches the bottom of your vehicle, causing it to stall or function improperly.
- A foot or higher of water on roads, which causes numerous vehicles to float.
- Two feet or more of running water flowing through streets. This is especially dangerous since most vehicles, including trucks, will be carried away.
- Never drive across a flooded street. Water depth is typically not obvious. Flooding often strips roadways, which could cause serious tire damage and other problems.
- Do not ignore barricades. Barricades keep motorists out of dangerous areas. Turn around and follow designated routes.
- Avoid taking short cuts since they’re typically blocked. Stay on marked evacuation routes.
- Be cautious while night driving since it’s harder to identify visible flooding hazards.
What to Do During a Flood
Follow these tips if a flood hits your area:
- Remain updated by following local radio and TV broadcasts.
- Remain vigilant for flash flooding. If you suspect potential flash flooding, relocate to higher ground at once. Don’t wait for instructions.
- Identify nearby streams, canyons, and drainage channels susceptible to sudden flooding. Flash flooding is possible in these areas, regardless of heavy rainfall.
Follow these steps while preparing for evacuation:
- Lock the home. Time permitting, place outdoor furniture and other objects inside. Place important objects on the highest floor.
- Turn off gas and other utilities if ordered by local authorities. Disconnect appliances and other electrical devices. Never operate electrical devices while standing in water.
Follow these evacuation tips if it’s necessary to leave your house:
- Never walk through streams of moving water. Moving water 6 inches or deeper can knock you over. Only walk in non-moving water. Utilize a stick to check ground for firmness.
- Never drive across flooded roads. If your vehicle begins to rise, leave it immediately and relocate to higher ground. Vehicles can be quickly swept away during flooding.
- Avoid camping near creeks, rivers, or streams, especially if flooding hazards are present.
What to Do After a Flood
If you’re home has been damaged, follow these tips after flooding has receded:
- Utilize local warning systems and alerts to remain updated about local conditions.
- Steer clear of moving water.
- Avoid damaged regions unless a police officer, firefighter, or relief agency has requested help.
- Steer clear of main roads since emergency personnel will be helping people trapped in flooded regions.
- Remain cautious. Flash or additional flooding can hit your area. Pay attention to local broadcasts and warnings. Evacuate to higher ground if you’re traveling in a car that stalls suddenly.
- Return home after instructed by local officials.
- Never travel through barricaded roads. Find alternative routes.
- Adhere to these tips if driving or walking through flooded regions:
- Remain on stable ground. You can be swept away by 6 inches or more of water. Likewise, water pools can be electrically charged since floods often knock power lines to the ground.
- Flooding typically causes alterations to familiar locations. Walkways and roads often become eroded following flooding. Flood debris often conceals broken glass, animal carcasses, and other objects. Do not walk through flood water since it’s slippery.
- Remain cautious in areas where floodwater has receded. Roads are often dangerous to drive on in recently flooded areas.
- Avoid structures surrounded by floodwater.
- Be careful while entering damaged buildings since floodwater can cause foundation damage.
Staying Healthy Flooding creates emotional and physical stress. Follow these steps to protect your health during flood cleanup:
- Steer clear of floodwater since it could contain sewage, oil, and dangerous chemicals.
- Repair damaged septic tanks, pits, cesspools, and leaching systems immediately. Damaged sewer systems pose severe health risks.
- Follow local news broadcasts to know when contaminated water is safe again.
- Disinfect and clean wet objects. Floodwater mud is often contaminated with chemicals and sewage.
- Eat nutritious food and rest frequently.
- Effectively manage your schedule. Develop and follow to do lists.
- Seek assistance if necessary and talk about concerns with relief agency representatives. The Red Cross provides emotional support to floodwater victims.
Cleaning Up and Repairing Your Home
- Regardless of whether local power has been switched off, use the fuse box or main breaker to turn the power off. Only turn power on when you’re 100 percent positive it’s safe.
- Obtain a book from the Red Cross entitled Repairing Your Flooded Home. It instructs flood victims how to:
- Reoccupy homes safety.
- Prevent additional damage.
- Document flood damage to present to insurance companies.
- Recognize water and gas leaks.
- Clean floors, furniture, and appliances.
- If necessary, obtain a cleanup kit from the Red Cross. These kits contain cleaning supplies, a bucket, and a mop.
- Discuss compensation options with you insurance company.
- Learn about federal and state government flood-recovery assistance programs.
- Always check the references of professionals hired to repair home damage. Be cautious of individuals soliciting door-to-door offering professional repair services.
Damage caused by flooding is not typically covered under a renter and homeowner’s insurance policy. FEMA manages the National Flood Insurance Program (NFIP), which provides consumers with federally-backed flood insurance available in communities that agree to adopt and enforce floodplain management ordinances to reduce future flood damage.
Flood insurance is usually offered in most communities through insurance agencies.
If you’re considering purchasing a flood insurance policy you should know that there is a standard 30-day waiting period before flood insurance goes into effect.
Last update 2021-04-08. Price and product availability may change.