BISMARCK, N.D. -- Emergency management officials in North Dakota are urging residents with basements flooded by the recent storms to use caution when pumping them out. Removing all of the water at once may cause serious structural damage to the house.
Draining the water too fast could cause the collapse of the cellar walls, floors, and foundation. The water must be drained slowly to equalize pressure on both sides of the wall, federal and state disaster response coordinators from the state of North Dakota and the Federal Emergency Management Agency indicated.
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 the basement is pushing back. If basements are drained faster than the water on the outside 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.
Officials recommend the following procedures be followed when pumping basements to avoid serious damage, collapse, or injury to occupants:
- Begin pumping when floodwaters are no longer covering the ground outside.
- 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.
The officials said they understand people are anxious to return home and begin the clean-up but urged caution, as the expense of rebuilding collapsed walls could be more than the cost of clean-up from the flood.