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Sump Pumps
A sump pump is an automatic water pump installed below grade to remove unwanted groundwater build-up that threatens to encroach on living space.

It is mounted in a pit recessed in the sump, or ground area around a home's basement foundation. This is generally in the deepest part of the foundation, and it's normally placed inside the house. In new construction, this pit is connected to the drainage tile buried around the foundation, the purpose of which is to collect and divert groundwater.

As groundwater rises and seeps into the pit, it triggers the float valve attached to the sump pump and activates the motor, which then pumps the water from the pit through a drainpipe or hose to a safe location away from the house.

It should not be permitted to pump this water into a sanitary sewage system, only a storm sewer or above the ground. By removing this water below grade, it cannot seep into the basement and damage property.

1. Pedestal pumps, where the motor is mounted at the top of a pedestal, above the water line, where it cannot get wet. This is the original style.
   
   
2. Submersible, where the entire pump fixture is mounted below the water level in the sump pit. This type has the advantage of being out of sight.
   
   
3. Battery backup pumps. These are powered by continually recharged deep-cycle batteries and mounted in the same pit as a submersible, ready to activate in an emergency when the primary pump fails for any reason.
   
   
4. Water-powered, where water pressure is used to pump the water out rather than an electric pump. This has the advantage of being able to work even during a power failure, but are not in common use due to the low volume of water they can pump.
   
   

Note: UPS (battery backup) modules can be added to electric motor-driven pumps to keep them running for a brief duration in the event of a power loss, but they offer no protection in the event of mechanical failure of the pump, so most homeowners purchase battery backup pumps instead. You can also install a separate alarm to alert you to a system failure.

• Inadequate gutters around the house, which allow rainwater to drain directly into the soil around the basement foundation.
  
  
• Negative grading, or the sloping of the ground around a house toward the house instead of away from it.
  
  
• House built in a low-lying area relative to the neighborhood. This will cause water to tend to flow toward the house rather than away from it.
  
  
• Poorly draining soil in a region that tends to experience heavy rainfall. When the ground becomes saturated with water, it will tend to follow the path of least resistance, or the basement.
  
  
• A naturally high water table in the area where the home is built. Nature establishes where this level will be, without asking the builder's permission.
  
  

• A sump pump should have an isolated electric circuit protected by a ground-fault interrupter.
  
  
• The pvc pipe serving as a discharge for the pumped water should include a check valve to prevent water from flowing back into the pit when the pump shuts off.
  
  
• The pump should be cleaned periodically to prevent the clogging of its protective screen.
  
  
• The discharge should exit at least 20 ft. away from the house, and never uphill, where the discharge could find its way right back into the sump.
  
  
• Optional alarms are available to warn the owner when the system fails
  
  

Choosing the Right Sump Pump
Pumps come in various sizes and capacities.

For most applications, a standard model will do quite nicely, but in those rare occasions where water seepage is particularly heavy or where the water has to be pumped a long distance, a larger capacity pump should be considered.

Sometimes, multiple pumps might be called for, in which case they may serve as emergency backups for each other.

In any case, some type of backup system is a good idea because if the pump fails, you may only have a few minutes to act to prevent your basement from flooding.

If you're handy, you can drive to one of our stores and buy a replacement, or you can place an emergency call to a plumber, but the chances are your basement will be flooded before a replacement unit can be installed. A backup system could be inexpensive insurance.

See Also:

Centrifugal Pumps
Recirculation Pumps
Sewage Ejector Pumps
Sump Pumps
Well Pumps

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