Title

Sump Pump Questions

(AE1573, Reviewed August 2021)
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Publication File:
Summary

For many homeowners the first line of defense against water in the basement is a sump with a pump in it. The sump may be connected to drain tile that drains the footings of the house, under the entire basement, or just the area where the sump is located. Many houses have tiling installed only around a portion of the house. The water that drains into the sump must be removed, and this is accomplished with a sump pump.

Lead Author
Lead Author:
Thomas Scherer, Extension Agricultural Engineer
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Availability:
Web only
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Water in the basement is always a concern when we receive a large amount of rain or snow. For many homeowners, the first line of defense is a sump with a pump in it.

The sump may be connected to tile that drains the area near the footings of the house under the entire basement or it may just drain the area where the sump is installed. Tiling can be installed on the outside or inside of the footings or both.

Many houses have tiling only installed around a portion of the house. Homeowners should try to determine what type of drainage system they have in the basement.

The water that drains into the sump must be removed, and this is accomplished with a sump pump. Sump pumps come in two basic models: the upright (commonly called a pedestal) and the submersible. Either will work well with proper maintenance.

The pedestal pump has the motor on top of the pedestal and the pump at the base, which sits on the bottom of the sump. The motor is not meant to get wet. The pedestal pump is turned on and off by a ball float. One advantage of this type of pump is the on/off switch is visible so the action of the ball float can be seen easily.

Submersible pumps are designed to be submerged in water and sit on the bottom of the sump. The on/off switch is attached to the pump and can be a ball float connected to an internal pressure switch or a sealed, adjustable, floating switch.

Both are reliable, but the floating switch requires a larger diameter sump. If the sump diameter is less than 18 inches, the floating switch or its cord could become entangled with the piping or pinned between the pump and sump.

Either type of pump should have a check valve on the water outlet pipe so water doesn’t flow back into the sump when the pump shuts off. Water flowing back and forth can cause the pump to turn on and off more frequently than necessary, which decreases the life of the pump.

Some frequently asked questions about sump pumps:

For More Information

• “Planning Ahead: Sump Pump Tips” video at www.youtube.com/watch?v=8P9b72wW8OQ 

• “Electric Backup Sump Pumps" (AE1771) publication at www.ag.ndsu.edu/publications/home-farm/electric-backup-sump-pumps-for-houses

• “Electric Backup Sump Pumps for Houses” video at www.youtube.com/watch?v=PPQvjRFVtxo

• “Backup Sump Pump Battery Selection, Installation and Maintenance” video at www.youtube.com/watch?v=ZGJPuGuRyL8

For more details about preparing for a flood and information about cleanup after a flood, contact your local NDSU Extension county office or visit the NDSU Extension Flood Information website at www.ag.ndsu.edu/flood.