What to Do After Your Basement Floods

Quickly take action to resolve flooding and mitigate expensive water damage.

Black mold in the corner of basement with mildew removal products

coja1108 / Getty Images

One of the more problematic issues that can occur in a home is flooding. When a basement floods because of excessive rain or meltwater from snow and ice and the problem is beyond just a leaky basement, it's important to take immediate action in order to help mitigate the damage to the home. Flooding can damage the foundation, drywall, carpet, hardwood floor, furniture, furnishings, and more. Even the basement ceiling and lighting can be impacted due to the significant increase in moisture inside the home.

However, some of the worst issues can occur after the water is cleaned up because areas that are out of sight, like under the floor or inside the walls, can become breeding grounds for mold and mildew if the home isn't properly cleaned and treated with an anti-mold solution. A high level of mold in the home greatly impacts air quality and can lead to the development of respiratory problems, among other health issues. Make sure that you know what to do after your basement floods to reduce the immediate damage and begin preparations for restoration.

  1. Turn off Electricity and Gas to the Flooded Area

    Before taking a step down into a flooded basement, it is imperative that the electricity is turned off to the flooded part of the home. If the electricity is not turned off, then the water could be conducting electrical currents from a short or a submerged power outlet. To avoid the risk of electrocution, turn off the electricity to the affected area of the home.

    In some cases, you may not be able to reach the breaker box to shut down the electricity. At this point, it's necessary to call a qualified electrician to shut down the electricity.

    Warning

    Never enter a flooded area while the power is on. Call a qualified electrician before entering the room if you aren’t sure how to shut these areas off.

    Similarly, you should shut down any gas appliances, like the hot water tank, gas dryer, or furnace. These appliances will need to be inspected before they can be turned back on to ensure that they were not damaged in the flood.

  2. Determine the Source of the Water

    Flooding can be the result of leaks in the foundation, clogged septic systems, broken pipes, or leaking fixtures. If the source of the flooding is from a burst pipe or leaking fixture, turn off the water to the home to stop the flooding.

    Water from a backed-up septic system won't continue to flood the home if the drains are not used, so it's a good idea to turn off the water to prevent further flooding in this case, as well. However, if the flooding is caused by excess rain, sleet, melting snow, or ice then you will need to locate the exact point where the water is entering the basement to control the leak with towels or buckets until you can have the foundation repaired by a professional.

    If the basement has a floor drain, make sure to keep it clear from obstructions so that the water can begin to drain out of your home. Just keep in mind that this floor drain is relatively useless if the problem was caused by a clogged septic system.

    Tip

    Finding the source of the leak is important for stopping the flood and fixing the initial issue, but before entering the basement make sure to wear boots, gloves, and a mask for protection. If the water level is higher than your boots, consider using hip or chest waders to stay dry while you work.

  3. Take Pictures and Call Home Insurance

    After you have a handle on the situation and have done what you can to stop the flow of water into your home, you need to pull out your phone or a digital camera and start taking pictures of the affected area. These pictures are your way of keeping a visual record so that you know what items were damaged, the current condition of the items, and what areas of the room were affected.

    This information will be very important when you contact your home insurance company. Just keep in mind that if you didn't sign up for flood coverage, then you may be stuck shouldering the costs of the damage.

  4. Drain the Water out of the Basement

    The water that has accumulated in the basement may drain out through the floor drain after you find the source of the flooding and shut it down. However, if you don't have a floor drain, the floor drain is clogged, or the floor is sloped in such a way that prevents the water from naturally draining, then the water is stuck in the basement until you find a way to remove it.

    Mops and buckets are a good way to start, but it will be much easier to move a large volume of water with a pump or even a wet/dry shop vac. When most of the water has been removed, switch to towels, cloths, and sponges to soak up the remainder of the water.

  5. Remove Damaged Items

    The damaged items in the basement, like couches, chairs, tables, bookcases, and other furniture, need to be moved into a dry, well-ventilated area. If the items stay in the basement, even if all of the water is cleaned up, they will take much longer to properly dry and may begin to grow mold or mildew in unseen locations, like the cushions of a couch.

    Prepare an area in a shed or garage where the items can be stored while they dry. If the weather permits, consider putting the items out in the sun to help them dry out quicker. Any items that are still wet or damp after about 48 hours may have already developed mold and mildew. Consider which items can be kept and which items will need to be thrown out.

    Warning

    Don't pick up electrical items, like a television, lamp, or game system. While the risk is low that the items will shock you if the electricity is turned off, there is the potential for further damage by moving the device, causing water to flow into previously dry areas. If at all possible, leave electrical items in place to dry or remove them carefully with insulated gloves.

  6. Dispose of Damaged Walls and Flooring

    In most circumstances, the flooring in the area of the basement that was flooded will need to be torn up and thrown out. Whether you have carpet, tiles, adhesive laminate, or hardwood flooring, extensive water damage is typically irreparable. Saturated laminate and tile come loose in patches, while both hardwood and carpet absorb and retain moisture, quickly becoming a breeding ground for mold and mildew.

    While you are ripping up the flooring, it's also advised to take out any underlay or plyboards. If you have a raised floor, the 2x4 support beams can usually be dried out and reused, but they will need to be treated with anti-mold spray to prevent mold and mildew growth. Wet and damaged drywall and insulation will also need to be taken out and replaced, though the drywall framework can, in most cases, be left in place to dry.

  7. Set up Fans and Dehumidifiers

    Leaving the basement empty and relatively water-free isn't enough to prevent the growth of mold and mildew throughout your home. The goal is to rapidly dry the floors, walls, and any objects that were left in the basement to dry, but you also need to remove the excess water from the air.

    The best way to thoroughly dry out the basement is to open any windows (weather permitting) then set up one or more fans to help improve the air circulation in the area. One or more dehumidifiers will pull moisture from the air and collect it in a bucket that you will need to empty about once every 4 to 6 hours. If you don't have fans or a dehumidifier, you can typically buy or rent them from your local hardware store.

  8. Wash the Floors and Walls

    Adding more water may seem counterproductive, but when the basement is completely dry you will still notice a lingering musty smell. Use a disinfecting cleaner that's safe for the floors and walls to help clean off any residual dirt and grime while killing viruses, bacteria, and fungi that may have been in the water.

    A scented cleaner is a great way to help remove the smell: Just make sure to wear a mask and that the basement is properly ventilated to avoid inhaling powerful cleaning chemical fumes while you work.

  9. Treat All Affected Surfaces With Anti-Mold Spray

    Even after cleaning the floors and walls with a disinfectant, mold and mildew can still begin to grow in unexpected locations. To help eliminate any existing mold and prevent the growth of mold and mildew in the basement, use an anti-mold spray on all affected surfaces. This includes flooring, framework, walls, ceilings, exposed insulation, and any other objects that could be vulnerable to mold and mildew.

  10. Make Repairs to Prevent Future Flooding

    When you have cleaned up the mess and ensured that the basement will not be subjected to ongoing water damage and mold growth, it's time to deal with the main problem. If the leak was caused by a broken pipe or plumbing fixture, call a plumber to assess the damage and make the necessary repairs.

    Foundation experts can inspect and advise on the next steps for repairing foundation cracks and leaks, while you would need to speak to a plumbing company that specializes in septic system maintenance and repair to begin the process of emptying and unclogging your septic system.

    If the primary cause of the flood is not addressed and resolved flooding is likely to reoccur.

Article Sources
The Spruce uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Dealing With and Preventing Mold in Your Home. University Of Minnesota Extension.

  2. A Brief Guide to Mold, Moisture and Your Home. United States Environmental Protection Agency.

  3. Flood Waters or Standing Waters. Centers for Disease Control and Prevention.