Flood Preparedness Guide: What to Do Before, During, and After a Flood
Floods kill more Americans every year than tornadoes, hurricanes, and lightning combined. The National Weather Service reports that flooding causes an average of 88 deaths per year in the United States, and the damage costs billions of dollars annually. What makes that number so striking is how many of those deaths happen in places people think of as safe, including city streets, highways, and suburban neighborhoods far from any river.
You do not need to live next to a river to be in danger. Flash floods happen in every state. Storms dump more rain than storm drains can handle. Levees fail. Roads flood and trap drivers. Urban areas with lots of concrete and asphalt send water rushing into intersections faster than anywhere else.
Flood preparedness is not just for people who live in a floodplain. It is for everyone. This guide will walk you through exactly what to do before, during, and after a flood so that your family stays safe when water starts rising.
Why Trust This Guide?
This article was researched and reviewed by contributors with hands-on experience in emergency preparedness. They have tested gear, built real systems, and lived through situations where these skills actually mattered.
Why Floods Are More Dangerous Than Most People Think
Most people picture a flood as water slowly rising over days, giving plenty of time to prepare and leave. That is not how most deadly floods happen.
A flash flood can turn a dry creek bed into a roaring wall of water in minutes. The water does not need to be deep to be deadly. Moving water that is only six inches deep can knock a person off their feet. Two feet of moving water can carry away most cars, including SUVs and pickup trucks.
Here are some facts that change how people think about flood risk:
About two thirds of flood deaths in the United States involve vehicles. People try to drive through flooded roads and get swept away. The phrase “turn around, don’t drown” exists for this exact reason.
Floods are the most expensive type of natural disaster in the country. Between 1980 and 2024, floods caused over one trillion dollars in damage across the United States, according to NOAA.
More than 40 percent of FEMA flood insurance claims come from properties outside of high-risk flood zones. Being outside the official floodplain does not mean you are safe.
Heavy rain upstream can cause flooding hundreds of miles away from where it rained. A flood in your area might have nothing to do with local weather.
Floodwater is almost never clean water. It carries sewage, chemicals, motor oil, pesticides, and bacteria. Contact with it creates real health risks, and so does breathing the air inside a flooded building after the water goes down.
Understanding Your Flood Risk
Before you can prepare, you need to know what kind of flood risk you face. Not all flood risk is the same.
Flood Zones and FEMA Maps
FEMA publishes flood maps for most of the country called Flood Insurance Rate Maps, or FIRMs. These maps divide land into flood zones based on how likely they are to flood in any given year.
Zone AE or Zone A means high risk. Properties here have a one percent chance or more of flooding in any given year. That sounds small, but over a 30-year mortgage it adds up to a 26 percent chance of flooding. Flood insurance is required for federally backed mortgages in these zones.
Zone X (shaded) is moderate risk. These areas have a 0.2 percent annual flood chance, or they are protected by a levee. Insurance is not required but is a good idea.
Zone X (unshaded) is low to minimal risk. But remember, over 40 percent of claims come from these zones.
You can check your flood zone by entering your address at the FEMA Flood Map Service Center at msc.fema.gov. It is free and takes about two minutes.
Levees Are Not Guarantees
Many cities and towns rely on levees to protect against flooding. Levees reduce risk but do not eliminate it. They can fail, overtop in extreme storms, or be overwhelmed by water that was not anticipated when they were designed. If a levee near you protects your area, find out when it was last inspected and what it was designed to handle. The Army Corps of Engineers maintains a National Levee Database at levees.army.mil.
Flash Flood Risk Factors
Even if your neighborhood is not near a river or in a named flood zone, you may still face flash flood risk. High flash flood risk areas include:
- Low-lying land that collects runoff from higher ground
- Streets near storm drains that overflow during heavy rain
- Areas near culverts or small streams that can fill quickly
- Canyons and ravines in arid regions where water rushes in from distant storms
- Areas with a lot of pavement that sheds water instead of absorbing it
Local Resources
Your county emergency management office often has more detailed local flood information than federal maps. Many counties publish flood hazard maps, historical flood records, and storm drain capacity data. A call to your local emergency management office can give you a much clearer picture of your specific risk.
Flood Insurance: A Critical Piece of Preparation
Standard homeowners insurance does not cover flood damage. This surprises a lot of people when they file a claim after a flood. By that point, it is too late to get coverage.
There are two options for flood insurance.
National Flood Insurance Program (NFIP). The federal government runs this program through FEMA. Most homeowners and renters can buy NFIP coverage through their insurance agent. There is a standard 30-day waiting period before coverage takes effect, so you cannot buy it when a storm is approaching and expect to be covered. Maximum coverage is $250,000 for a building and $100,000 for contents.
Private flood insurance. Private insurers offer flood coverage that can cover higher amounts, have shorter waiting periods, and sometimes cost less than NFIP. If you have a high-value home or need more than the NFIP limits, compare private options.
If you rent, your landlord’s insurance covers the building but not your belongings. Renters flood insurance is available through NFIP and private carriers. It is usually affordable and worth having in flood-prone areas.
Building Your Flood Emergency Kit
A flood emergency kit is similar to a general emergency kit but has some specific additions. Here is what to prioritize.
Water and Purification
Flooding often contaminates municipal water supplies. Even if tap water looks clear, it can carry bacteria and chemicals that make it dangerous. Have at least one gallon of clean water per person per day stored, plus purification tools in case you need more.
The LifeStraw Family Water Filter can purify up to 18 liters per hour and removes bacteria, parasites, and microplastics. It is a solid backup for treating questionable water when your tap is not safe.
Water purification tablets are a compact backup. Potable Aqua Iodine Water Purification Tablets treat a liter of water in about 35 minutes and take up almost no space in a bag or kit.
Emergency Radio
When power goes out and cell service fails, a battery-powered or hand-crank radio is how you get official information. The Midland ER310 Emergency Crank Weather Radio receives NOAA Weather Radio, which broadcasts official flood watches and warnings. It has a hand crank, a solar panel, USB charging, and a built-in flashlight. It works when nothing else does.
Power Backup
Flooding often knocks out power for days. A portable power station can keep phones charged, run medical devices, and power lights without the carbon monoxide risk of a gas generator indoors.
The Jackery Explorer 300 Plus holds enough charge for dozens of phone charges, a CPAP machine overnight, or a small lamp for extended use. It recharges via wall outlet, car outlet, or solar panel.
If you use a gas-powered generator, keep it outside and at least 20 feet from any window, door, or vent. Carbon monoxide from generators kills people every year during power outages. A First Alert carbon monoxide detector is essential anywhere a generator, grill, or camp stove is used near living spaces.
Waterproof Document Storage
When flood water enters your home, the first things to grab are your important documents. But during a rapid evacuation, grabbing individual papers wastes precious time.
Keep copies of these documents in a waterproof case or bag, ready to grab:
- Passports and birth certificates
- Insurance policies (home, flood, auto, health)
- Social Security cards
- Property deed or lease
- Vehicle titles
- Medical records and medication lists
- Recent photos of your home’s contents for insurance purposes
The Pelican 1200 Case is dustproof, waterproof to IP67 standards, and virtually crush-proof. Many people keep one permanently packed with documents and a USB drive containing digital copies of everything.
For a simpler option, a waterproof document bag with zipper seal costs under twenty dollars and keeps papers dry when submerged.
Protective Gear for Cleanup
Post-flood cleanup exposes you to contaminated water, mold, and debris. You need the right gear before you go back in.
Rubber boots. Thick rubber boots protect your feet from contaminated water and sharp debris. Look for knee-high or hip-high waders for serious flooding. Muck Boot Company rubber boots are a trusted option that many flood response volunteers use.
Nitrile gloves. Disposable nitrile gloves protect your hands from chemical and biological contamination. Dynarex nitrile gloves come in boxes of 100 and hold up better than latex under wet conditions.
N95 respirators. Mold grows rapidly in flood-damaged buildings, often within 24 to 48 hours of water intrusion. An N95 respirator filters 95 percent of airborne particles. The 3M Aura N95 respirator has a three-panel design that makes it easier to breathe during sustained work.
Eye protection. Debris, mold spores, and chemical splashes are all hazards during flood cleanup. Basic safety glasses or goggles are important personal protective equipment.
Portable Water Pump
If water enters your basement or home, removing it quickly reduces structural damage and mold growth. A submersible pump can move hundreds of gallons per hour.
The Wayne 1/2 HP submersible sump pump moves up to 3,700 gallons per hour and can handle small solids that get mixed in with water. Running a garden hose to a drain or out a window lets you remove water even when electricity is out if you pair it with a generator.
Protecting Your Home Before a Flood
If you know flooding is coming, there are things you can do to reduce damage. The time available depends on the type of flood. A river flood might give you days. A flash flood might give you minutes. Know your risk and have a plan ready.
Temporary Flood Barriers
Sandbags are the traditional tool for redirecting water. They work, but they require a lot of labor to fill and place, and getting the sand takes time and planning. If sandbags are part of your plan, stockpile bags and have a source of sand identified before you need them.
Water-activated flood barriers are a faster alternative. The AquaDam FloodSax expands when it absorbs water and forms a barrier against incoming flood water. Each bag weighs only a few ounces when dry but expands to a 20-pound barrier within minutes of contact with water. They store flat in a closet and can be deployed without any lifting of heavy sand bags.
Door flood barriers, sometimes called door dams, create a seal around door frames to prevent water from entering. The Quick Dam Flood Barrier slides into place in front of a door and activates when it gets wet. These work well for keeping small amounts of water out during localized flooding.
What to Move or Turn Off
When a flood is possible, take these steps before you leave or before water arrives:
Move valuables, electronics, and important documents to upper floors. Even moving things to countertops can protect them from a few inches of water.
Turn off the electricity at the breaker if water is entering or about to enter your home. Electricity and water together create electrocution risk. Only turn power off if you can reach the breaker panel without stepping through water.
Turn off the gas at the main shutoff if you are evacuating. This prevents gas leaks if appliances are disturbed by flood water.
Move your vehicles to higher ground early. Do not wait until water is already on the roads.
Take photographs of your home, furniture, appliances, and electronics before you leave. These photos help with insurance claims later.
Bring in outdoor furniture, toys, grills, and anything else that could be carried away or damaged.
Longer-Term Home Flood Proofing
If you live in a flood-prone area and you own your home, there are more permanent steps worth considering.
Sump pump with battery backup. A sump pump removes water that enters your basement. The battery backup keeps it running during power outages, which often happen during the same storms that cause flooding. The Zoeller M53 sump pump is one of the most recommended options for residential use.
Backwater valve. A backwater valve on your sewer line prevents sewage from backing up into your home when municipal sewer systems get overwhelmed. This is a plumber installation but pays for itself after one major storm.
Flood vents. Flood vents allow water to flow through foundation walls and back out, equalizing pressure instead of letting it build up and crack foundations. They are required in new construction in many flood zones.
Raising electrical outlets and appliances. Moving electrical panels, outlets, and appliances like water heaters and HVAC units above the base flood elevation dramatically reduces damage and speeds up recovery.
Flood Watches, Warnings, and Advisories
Understanding flood alerts from the National Weather Service helps you know how to respond at the right time.
Flood Advisory. Minor flooding is possible, often in low-lying areas. Pay attention and be ready to act. This is the time to check your kit and know your route.
Flood Watch. Conditions are favorable for flooding. Flooding is possible but not certain. This is your signal to prepare to leave. Charge devices, pack your bag, move valuables to upper floors, and fill your gas tank.
Flood Warning. Flooding is occurring or will occur soon. Move to higher ground immediately if you are in a flood-prone area. Do not wait to see the water.
Flash Flood Warning. This is the highest urgency alert. Flash flooding is happening now or is imminent. Take action immediately. Move to higher ground without delay.
Flash Flood Emergency. Rare. Issued only for extreme events with a serious threat to human life and widespread catastrophic damage. This is a life-threatening situation requiring immediate action.
Sign up for your county’s emergency alert system so you receive flood warnings automatically. Most counties use Nixle, Everbridge, CodeRED, or a similar platform. Search for your county name and “emergency alerts” to find the sign-up page. Also enable Wireless Emergency Alerts on your phone, which pushes official alerts without needing an app or data connection.
What to Do During a Flood
The Most Important Rule: Never Drive Through Flooded Roads
Sixty-three percent of flood deaths happen in vehicles. The danger is real and it is underestimated. Here is why:
It only takes six inches of water to stall most cars. Twelve inches of water can carry away a small vehicle. Two feet of water can carry away nearly any car or truck. At night or in murky water, you cannot judge the depth from the road surface. What looks like four inches can be four feet.
Concrete roads can wash out beneath flood water, leaving nothing under your tires while the surface looks intact. Flowing water that crosses a road is almost always faster and deeper than it appears.
If water is flowing over a road, stop. Turn around. Find another route. No destination is worth your life. This applies even if other cars went through before you. Water levels can change in seconds.
If your car stalls in rising water, get out immediately and move to higher ground. Do not wait. A car can be replaced. Do not be the person who drowns in a car trying to save the car.
If Water Enters Your Home
If water begins rising inside your home, move to higher floors. Do not go to the attic unless you have a way to escape, such as a roof hatch or attic window. People have drowned in attics after becoming trapped by rising water with no way out.
Turn off electricity at the breaker if you can safely reach it without stepping through standing water. Water conducts electricity, and a live circuit in a flooded room can electrocute you.
Do not use any open-flame or gas appliances during a flood. Flooding can disturb gas lines.
Charge your phone and contact local emergency services if you are trapped. Tell them your location, the number of people with you, and whether anyone needs medical attention. Text messages often get through when calls cannot.
If you must leave through water, move carefully. Use a long stick to probe ahead of you and check depth and footing. Avoid moving water whenever possible. Even slow-moving water with debris in it is dangerous.
Sheltering in Place vs Evacuating
In a river flood with days of warning, evacuating early is almost always the right call. Once roads begin to flood, evacuation becomes dangerous. Leave before the water arrives.
In a flash flood, you usually have no choice. Get to the highest point you can reach, whether that is the second floor of a building, a hill, or a bridge overpass. The goal is elevation and staying out of moving water.
Sheltering in place on an upper floor makes sense when:
- You cannot safely reach your car without going through water
- Roads around you are already flooded
- Emergency services have told you to stay put
- You are above the expected flood level
Evacuating makes sense when:
- You receive a mandatory evacuation order
- Your home is in a low-lying area
- You have enough time to leave before roads flood
- You or a family member has a medical condition requiring reliable power or temperature control
Evacuation Routes and Plans
Know your evacuation routes before a flood threatens. Your normal route may be the first one to flood. Have at least two alternates planned.
Your evacuation plan should include:
Where you will go. Know your destination before you need it. This could be a family member’s home, a hotel, or an official emergency shelter. Your county emergency management office publishes shelter locations. Know two options in case one is full or inaccessible.
How you will get there. Identify routes that stay on higher ground. Avoid routes that cross creeks, rivers, or low-lying bridges. Identify which roads in your area flood first so you can avoid them.
How you will communicate. Agree on a contact person outside your area for family members to check in with if local phone service is jammed. Text messages use less network capacity than calls and get through more reliably during emergencies.
What you will take. Your go bag, your pets, your medications, your documents. Know where all of these are. Keep them together.
What happens if you are separated. Tell every family member what to do if you cannot reach each other during an evacuation. Where to meet. Who to call. Where the plan is written down.
After the Flood: Returning Home Safely
Returning home after a flood feels urgent. People want to see their belongings and start cleaning up. But returning too soon is dangerous. Wait for official clearance from local emergency management before going back.
Before You Enter
Walk around the outside of your home before you go in. Look for:
- Structural damage like foundation cracks, leaning walls, or a shifted foundation
- Sagging roof sections or collapsed porches
- Gas smell around the building
If you see structural damage, do not enter. Call a building inspector first. A structurally compromised building can collapse without warning.
If you smell gas, stay out, call your gas company, and wait for them to turn off the supply before entering.
When you are ready to enter, wear rubber boots, nitrile gloves, N95 respirators, and eye protection. This is not optional. Floodwater contains human sewage, E. coli, hepatitis A, and dozens of chemical contaminants. Every surface that was submerged is contaminated.
Electrical Safety
Do not turn on electricity until a licensed electrician has inspected your electrical system. Submerged wiring, outlets, and electrical panels can be damaged in ways that are not visible. Turning power on to damaged wiring starts fires.
If you have a gas-powered generator, keep it at least 20 feet from windows, doors, and vents, and run it only outside. Keep a carbon monoxide detector near any room where people are sleeping.
Documenting Damage for Insurance
Before you clean up or throw anything away, photograph and video everything. Walk through every room. Document every damaged item. Capture the water line on walls to show how high the water reached. Your insurance company will need this evidence.
Make a written list of damaged items, including approximate values and purchase dates. Keep all receipts for emergency repairs, supplies, and hotel stays. These are often reimbursable under flood insurance policies.
Contact your insurance company as soon as possible to start the claims process. FEMA disaster assistance may also be available if your area has a federal disaster declaration. Register at disasterassistance.gov.
Drying Out Your Home
Mold begins growing within 24 to 48 hours of water intrusion. The faster you remove moisture, the less damage it causes. Speed matters.
Remove standing water with a submersible pump or wet-dry vacuum. Tear out wet drywall and carpet as soon as possible. Wet drywall and insulation cannot be dried in place and must be removed to prevent mold.
Open windows and doors when the outside air is drier than the inside air. Run dehumidifiers continuously. Run fans to move air across wet surfaces.
Mold remediation for severe cases is a professional job. The EPA recommends hiring a professional for mold contamination covering more than 10 square feet. For smaller areas, use a commercial mold killer and follow label instructions carefully, using gloves and an N95 respirator throughout.
Health Risks After a Flood
The health dangers after a flood are significant and should not be ignored.
Contaminated water. Do not drink tap water until authorities declare it safe. Boil advisories may be in effect even when water looks clear. Stick to stored water or water you have purified yourself.
Mold exposure. Mold causes respiratory problems, allergic reactions, and in high concentrations can cause serious illness. Wear an N95 respirator any time you are inside a flood-damaged building.
Wound infections. Even minor cuts exposed to floodwater can become seriously infected. Clean any cuts thoroughly and watch for signs of infection including redness, swelling, warmth, and increasing pain. See a doctor if any wound becomes infected after flood water exposure.
Mental health. Losing your home or belongings to a flood is traumatic. The process of recovery is long and exhausting. Serious stress reactions, depression, and anxiety are common after major flood events. Take these seriously and seek help from a mental health professional or through FEMA’s crisis counseling programs if you are struggling.
A Flood Preparedness Checklist You Can Actually Use
Most checklists are too long and vague to be useful. This one is organized by when to do each item.
Special Considerations for Apartments and Urban Areas
Living in an apartment or a city changes how you think about flood risk. You have less control over your building but you face some unique challenges and advantages.
High-rise apartments are generally safer from flooding as long as you are above the ground floor. However, flooding can knock out elevators, disrupt water pressure, and cut off access to the building. Keep enough supplies on hand to shelter in place for several days.
Ground floor and basement apartments face more direct flood risk. Know your building’s history with flooding. Know how quickly you need to leave if rain starts. If your apartment has flooded before, take that seriously when planning.
Urban flash flooding happens fast and in places people do not expect, including streets, subway stations, and underpasses. During heavy rain, avoid low-lying routes. Watch for water pooling in intersections. If you drive, know which roads in your neighborhood flood first and avoid them.
Community organizing matters in urban settings. Priya K., one of our contributors who runs a neighborhood preparedness group in Chicago, emphasizes the value of knowing your neighbors. During a flood, the people around you are often your first source of help. Knowing who needs assistance and having a communication plan for your building or block makes a real difference.
Preparing Pets for Flood Evacuation
Pets are family. They need to be part of your flood plan.
Know in advance which emergency shelters in your area accept pets. Many public shelters do not. Have a backup option: a pet-friendly hotel, a boarding facility that stays open during emergencies, or a friend or family member outside the flood zone.
Keep a pet emergency kit ready that includes:
- Several days of food and medication
- Bowls and a water supply
- Carriers or crates for every pet
- Copies of vaccination records
- Photos of you with your pet (helpful if you get separated)
- Leashes, harnesses, and collars with ID tags
Do not leave pets behind during a flood evacuation. Animals left inside flooded homes frequently do not survive. If you do not have a way to take them, start making those arrangements now, before a flood is in the forecast.
Final Thoughts: Do This Today
The most important thing about flood preparedness is doing something now rather than waiting until a storm is in the forecast. Once the rain starts, your options narrow fast.
Three things you can do today that will make a real difference:
Check your flood zone. Go to msc.fema.gov and look up your address. Know whether you are at elevated risk.
Sign up for flood alerts. Find your county’s emergency notification system and add your phone number and email. It takes five minutes.
Review your insurance. Pull out your homeowners or renters policy and read what it says about flood damage. If flood is not covered, talk to your insurance agent this week about your options.
Those three steps cost nothing and take less than an hour. They are the foundation everything else builds on. Do them before the next storm season arrives, and you will be in a very different position than most of your neighbors when the warnings start coming in.
Floods are predictable events in most parts of the country. That is actually good news. It means there is time to prepare. Use it.