How do sump pumps work?

Sump pumps are activated by water levels and, when switched on, pump water away from the foundation or basement of a building. They are used to protect the structure of a building from water. This could be water from rain or water that comes up through the ground.

A sump pump is usually located in a corner of a basement or in a crawlspace. Typically it is at the bottom of a pit. The floor of the area is laid so that water flows towards and into this pit. Once the water gets to a certain level, the pump automatically switches on and starts to pump the water from the pit to the outside of the building.

There are two main types of sump pump:

• Pedestal sump pump - the motor of a pedestal pump sits on a pedestal so that it never goes underwater. A pipe runs from it to the bottom of the pit. When the water level reaches a certain point the motor is switched on, and the water is pumped up through the pipe.
• Submersible sump pump - this type of sump pump sits at the bottom of the pit, under the water. The water is sucked up through the pump, which is protected by a screen or grate from gravel and stones.