How fast should I pump water out of a flooded basement?

If the ground outside was flooded, gradually: FEMA recommends pumping about a foot a day at first and waiting to see whether the water returns, because draining too fast can let outside pressure crack or collapse walls.

How quickly do I need to dry a flooded basement?

The EPA advises drying wet materials and furnishings within 24 to 48 hours to prevent mold.

Can I run a generator in the basement to power the pumps?

No. Never run gasoline generators or pumps indoors. Keep generators outside, at least 20 feet from windows, doors and vents.

Does insurance cover a flooded basement?

It depends on the source. Floods need flood insurance; sewer and sump pump backups usually need a water backup add-on; groundwater seepage is usually excluded.

What to Do After a Basement Flood: Step-by-Step

1. Safety first

Electricity: don’t step into standing water if it may reach outlets, cords, the furnace or appliances. Shut off power to the basement at the panel only if you can reach it safely; otherwise call the electric utility.
Gas: if you smell gas, leave and call the gas company from outside.
Carbon monoxide: never run gasoline pumps or generators inside the house or basement. Keep generators outdoors, at least 20 feet from windows, doors and vents, as the Consumer Product Safety Commission recommends.
Contamination: water from floor drains or outside flooding can contain sewage. Wear boots, gloves and eye protection.

2. Document before you clean

Take photos and video of the water level, the damage, where water came in and damaged belongings (including model and serial numbers of appliances). Then call your insurance agent; many policies require prompt notice and steps to prevent further damage.

3. Pump out the water – gradually if the ground is flooded

If the area around your house was flooded, don’t pump the basement dry all at once. FEMA warns that saturated soil outside still pushes on the walls; draining the inside too fast can make walls or floors crack or collapse. FEMA’s recommended approach:

Start only when floodwater no longer covers the ground outside.
Pump out about 1 foot of water, mark the level and wait overnight.
If the water rises back above the mark, it is still too early – wait another 24 hours and repeat.
When the level stops rising, pump out 2 to 3 feet per day, checking each day, until the water is gone.

For a few inches of water from a failed sump pump or a backup, with dry ground outside, a wet/dry vacuum or utility pump is usually fine right away.

4. Dry everything within 24–48 hours

The U.S. EPA advises drying wet building materials and furnishings within 24 to 48 hours to prevent mold growth.

Remove wet carpet and pad, cardboard, paper and upholstered items.
Cut out soaked drywall and insulation, often a foot or more above the water line.
Run fans and dehumidifiers continuously; open windows only when the outside air is drier.
Clean hard surfaces; follow EPA mold guidance and consider professionals for large areas or sewage contamination.

5. Find out why it happened

Before you rebuild anything, identify the source: sewer backup (water from floor drains), groundwater (water along the walls or up through the floor), surface water (one spot, near a downspout or window well), a failed sump pump, or river/flash flooding. Each has a different fix – see water in the basement after heavy rain.

6. Insurance

Standard homeowners policies usually exclude flood and groundwater; sewer and sump pump backups are typically covered only with a water backup add-on.
Flood damage needs separate flood insurance (NFIP or private), which normally has a 30-day waiting period for new policies.
Keep receipts for cleanup equipment and professional services.

More: does homeowners insurance cover a wet basement?

7. Prevent the next one

A sump pump with battery backup and a water alarm.
A backwater valve if water came up through floor drains – see backwater valves.
Interior drainage for groundwater seepage.
Gutters, downspouts and grading that move water away from the house.
Furnace, water heater and electrical panel raised where flooding is likely; valuables stored upstairs.

What to do after a basement flood: step by step