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Emergency · Basement Flooded Right Now?

Basement Flooding Emergency — Act in the Next 60 Minutes

Standing water in your basement? Follow this exact sequence: safety first, pump planning, documentation, and when to call IICRC-certified pros before mold starts.

(888) 840-6512Mold window: 48 hours

Emergency checklist

  1. Do NOT enter a flooded basement if water may have reached electrical outlets — cut power at the main breaker first

    Electrocution risk is the #1 basement flooding hazard

  2. Identify the water source: groundwater seepage, sump pump failure, sewer backup, or supply line break

    Sewage backup (Category 3) requires full evacuation until decontaminated

  3. Photograph water depth marks on walls, damaged items, and the entry point before pumping

    Insurance adjusters need pre-cleanup evidence

  4. If safe and Category 1 water: use a submersible pump to remove standing water — never use a household vacuum

    Pump toward a drain away from the foundation, not into the yard toward the house

  5. Call an IICRC-certified restoration company — basement flooding requires commercial dehumidifiers and moisture mapping

    Consumer dehumidifiers cannot dry concrete walls or subfloor in time

  6. Call your insurer immediately — ask if sewer backup rider applies if water came from floor drain

    Standard homeowners insurance does NOT cover groundwater flooding without flood insurance

Typical cost range

$2,500$15,000

Full cost breakdown

Mold growth timeline

Mold Growth Clock

What happens hour by hour after water damage

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elapsed

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or click any marker
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Water Intrusion

lowHour 0

Water enters the structure. Clock starts NOW.

Recommended Action

Shut off water source, move valuables off floor, begin documentation with photos/video.

Next milestone: Absorption Begins at 1 Hour

All Milestones

Basement Flooded Right Now? FAQ

Is basement flooding covered by homeowners insurance?
It depends on the source. Burst pipes and appliance failures are typically covered. Groundwater seepage, sump pump failure (without a rider), and river flooding are usually excluded. Sewer backup may be covered only if you have a sewer backup endorsement.
Can I pump the basement myself?
For clean water (Category 1) from a broken supply line, yes — if electrical safety is confirmed. For gray or black water, or if water exceeds 2 inches and covers outlets, wait for professionals with proper PPE and extraction equipment.
How long before mold grows in a flooded basement?
Mold can begin colonizing within 24–48 hours in a humid basement. Concrete and block walls retain moisture for weeks without commercial drying equipment. Start professional drying within the first 24 hours.
How to Replace a Main Shutoff Valve | Ask This Old HouseThis Old House walks through locating, operating and replacing the main water shutoff valve — the most important emergency skill for limiting water damage. Read the full guide →