Draining the water from your basement too fast could cause the collapse of the cellar walls, floors, and foundation of the house. The water must be drained slowly to equalize pressure on both sides of the wall. Although the flood has receded, water still in the ground outside your house may be pushing hard against the outside of your basement walls. The water in your basement is pushing back. If you drain your basement faster than the water in the ground is draining, the outside pressure will be greater than the inside pressure and may cause the foundation, basement walls or floor to crack or rupture.
The Federal Emergency Management Agency (FEMA) and the Indiana State Emergency Management Agency (SEMA) recommend the following procedures be followed when pumping a basement to avoid serious damage, collapse, or injury:
- Begin pumping when floodwaters are no longer covering the ground outside.
- Pump water away from the home to avoid backpressure.
- Pump out one foot of water. Mark the water level and wait overnight.
- Check the water level the next day. If the level went back up (covered your mark) it is still too early to drain your basement.
- Wait 24 hours and then pump the water down one foot again. Check the level the next day.
- When the water in the basement stops returning to your mark, pump out two to three feet and wait overnight.
- Repeat daily until all the water is out of the basement.
