Water Damage Statistics

Last Updated: October 1, 2022

Report Highlights. Water damage statistics indicate even a minor leak can increase the average household water bill by 10%.

  • The average home insurance claim for water damage is $11,098.
  • 98% of basements experience some sort of water damage.
  • 14.6 million U.S. homes are at risk of flooding.
  • On any given day, home water damage emergencies effect 14,000 people.
  • Nationwide, household water damage costs up to $20 billion annually.
Typical Household Water Damage Costs
Type of Damage Total Cost*
Minor plumbing or fixture leak $100
Malfunctioning appliance $1,600
Single floor, 1 inch of water in a small home $11,000
Single floor, 1 foot of water in a single-family home $29,000
Heavy storm damage $38,000
Unfinished basement flooded with contaminated water $60,000
2nd floor contaminated water damage $100,000

*Including all repairs, replacements, and wastage.

Common Household Water Damage Statistics

Water damage and freezing as a category is the second-most common type of home insurance claim (following wind and hail).

  • Nationwide, household leaks waste an estimated one (1) trillion gallons, or enough to supply 11 million homes with water for a year.
  • 10% of homes with leaks waste 90 gallons daily.
  • A leaky faucet can waste 3,000 gallons per year.
  • A leak in an irrigation system can waste 6,300 gallons in a year.
  • An average household leak can waste up to 10,000 gallons of water in a year.
  • Annual water wastage from a typical household leak is equivalent to the water used for:
    • 270 loads of laundry.
    • 600 showers.
    • 1,200 loads of dishes in a dishwasher.
    • 6,250 flushes of a standard toilet.
    • 7,813 flushes of a WaterSense toilet.
    • 1,280,000 servings of water.

Weather and Water Emergency Statistics

Water damage can be an emergency, especially if the damage is weather-related. The most expensive home repairs are typically due to emergency water damage.

  • 99% of U.S. counties were impacted by a flooding event between 1996 and 2019.
  • Since 2000, flood damage has quadrupled.
  • The average flood claim payout from the National Flood Insurance Program is $52,000.
  • Flood insurance costs $700 annually.
  • One inch of floodwater can cause more than $25,000 damage.
  • Homes on floodplains are overvalued by an average of $11,526 each for nearly $44 billion.

Water Damage Health Risks

Water entering a home can harm the health and well-being of those living there.

  • Mold and mildew. The Center for Disease Control cites mold and mildew as significant health risks that can produce allergens, irritants, and toxic substances (mycotoxins).
  • Injuries. Aside from the obvious slip-and-fall, water is an excellent conductor of electricity; electrocution can cause permanent bodily damage and death.
  • Chemical hazards. Depending on where the water is coming from, it may bring toxic chemicals with it; this is most typical of water damage from natural disasters, such as floods.

The Environmental Protection Agency (EPA) recommends homeowners regularly check for leaks and advises that it is unlikely that a family of four would use more than 12,000 gallons per month.

Water Contamination Levels

The contamination levels in water influence clean-up costs of water damage.

  • Category 1 or white water originates from a hygienic source such as a water supply line or melted snow.
  • Category 2 or grey water has been exposed to contaminants, such as rainwater, bath or shower water, discharge from a washing machine or dishwasher, aquariums, etc.
  • Category 3 or black water is hazardous. It may contain pathogenic or toxigenic contaminants from sources like sewage, toilet backflows, seawater, river or lake water, and water containing toxic substances. This includes all floodwater.

Untreated Water Damage

Homes continue to deteriorate when water damage is left untreated. Left to sit, water damage goes through a general timeline:

Within Minutes

  • Carpets, padding beneath flooring, subflooring becomes saturated.
  • Furniture on wet carpets begins to leach and stain.
  • Wood and wood products begin absorbing water.
  • Personal belongings, such as photos and paperwork, may be destroyed.

Within Hours

  • Humidity begins to make the house stink.
  • Furniture in contact with water delaminates and swells.
  • Particleboard cabinetry and furniture distorts and weakens, crumbling over time.
  • Dyes from non-colorfast fabrics bleed (clothing stored together, upholstery, etc.).
  • In 48 hours or less, clean or grey water can deteriorate to black water, and in areas that experience water intrusion, clean water can rapidly become toxic.

Within Days

  • Fungi and mold becomes visible and causes musty odors
  • Allergen sensitivities can be caused by microbial organisms.
  • Wood may severely warp and cup, making most wooden floors unsalvageable.
  • Painted walls blister, and wallpaper begins to peel away.
  • Structural wood within the home, such as framing, begins to swell and split.

Within Weeks

  • Home is hazardous to human health and must be evacuated.
  • Mold infests organic materials, rendering it unsalvageable.
  • Drywall crumbles while the home’s structural integrity declines.
  • Damage to the foundation becomes apparent.
  • Home may be salvageable but may need to be gutted down to the studs.

Within Months

  • Damage to the foundation may be significant.
  • The cost of repairs is likely more than the home’s value.
  • Damage that could have been prevented over time (i.e., neglect) disqualifies the owner from insurance claims.
  • The home may be unsalvageable.

Water Intrusion

The level of water intrusion in a water damage event is measured by the amount of water, the materials affected, and the level of absorption, with Class 1 of water intrusion being the least dangerous and Class 4 the worst.

  • Class 1 indicates a minimal amount of water flow to the area, and materials are mainly low porosity, such as a tile floor. Little moisture remains after bulk water is removed, and a minimal amount of evaporation is needed for drying to complete. Can deteriorate to Class 2 or 3.
  • Class 2 is due to a significant amount of water flow into the area. Materials that got wet are medium to high porosity (carpet, gypsum wallboard). The scope of what got wet is confined to what flowed across a floor with adsorption into other materials. Can deteriorate to Class 3.
  • Class 3 indicates the greatest amount of absorption into materials, with the highest possible rate of evaporation needed after bulk water is removed. Includes major part of structural surfaces within the wet area, such as carpet, particleboard, wall, and ceiling boards.
  • Class 4 means the majority of moisture is trapped or bound within the building materials with a meager potential rate of evaporation after bulk water removal. Materials are typically low in porosity and may require special methods, longer drying times, or structure disassembly.


  1. Stanford News, Stanford Researchers Reveal that Homes in Floodplains Are Overvalued by Nearly $44 Billion
  2. United States Environmental Protection Agency (EPA), Fix a Leak Week
  3. EPA, Residential Toilets
  4. Centers for Disease Control and Prevention, Mold: Cleanup and Remediation
  5. Federal Emergency Management Agency (FEMA), Historical Flood Risks and Costs
  6. FEMA National Flood Insurance Program, Flood Risks and Costs
  7. Insurance Information Institute, Faces + Statistics: Homeowners and Renters Insurance
  8. FEMA, Flood Insurance and the NFIP