Before you go downstairs
If water is near outlets, the furnace, the water heater or the electrical panel, do not step into it. If the water came up through a floor drain, treat it as sewage. When in doubt, stay on the stairs and request service.
What happens after a basement floods
After a basement floods, water soaks into carpet pad, the lower edge of drywall, wall framing and anything stored on the floor. The concrete slab also absorbs moisture. Cleanup involves removing the water, discarding what cannot be saved and drying the structure before mold develops.
Why Anoka-area basements flood
Snowmelt
In March and April, snow melts while the ground beneath is still frozen. The water cannot soak down, so it moves toward foundations and window wells.
Groundwater and sandy soil
Much of Anoka County sits on the Anoka Sand Plain, where the water table is shallow in many neighborhoods. After a wet spell, groundwater rises to the level of the basement floor and the sump pump has to move it.
Summer storms
A heavy thunderstorm can drop more rain in an hour than gutters and grading can handle. Window wells fill and leak, and a storm that knocks out power also stops the sump pump. See sump pump failure cleanup.
Plumbing above
Not all basement water comes from outside. A burst pipe, a failed water heater or a washing machine hose on the main floor all end up downstairs.
The cleanup process
- Safety check of power and the type of water.
- Pump out standing water, then extract from carpet and floors.
- Remove carpet pad, wet cardboard and materials that will not dry.
- Open up where needed. Baseboards come off. Drywall may be cut a foot or two above the floor if insulation behind it is wet.
- Dry the slab, framing and remaining drywall with air movement and dehumidification.
- Clean floors and lower walls.
Finished versus unfinished basements
An unfinished basement with a bare slab and block walls is the simpler case: pump, clean and dry. A finished basement has carpet, framed walls, insulation and often a bathroom or bedroom. Water gets behind the finished wall and sits against the foundation where air cannot reach it. That hidden space is where most of the work is.
What can usually be saved
- Carpet, if the water was clean and it is handled quickly
- Drywall that is firm and was wet for a short time
- Solid wood furniture
- Framing, almost always
Pad, particleboard furniture, wet cardboard boxes and saturated insulation rarely are.
After the cleanup
Once the basement is dry, look at why it flooded. Extending downspouts, regrading soil near the foundation, adding window well covers and installing a battery backup on the sump pump prevent most repeat floods. Our flooded basement guide covers these.