Sump Pumps

What are they?

Sump pumps are used to remove water that accumulates in a basement or below a building’s foundation, or from equipment or floor drains in manufacturing plants. Residential configurations are most commonly used in areas where the normal water table is close to the surface, or in places that are prone to flash flooding or large, sudden snowmelt. The water collects in a sump pit—a tank mounted below the ground capable of collecting and retaining a prescribed volume of water. The pump then moves the water into the municipal sewer or storm water system, or, in the case of industrial applications, to a treatment process before discharge or reuse.

How do they work?

Ground water in the surrounding soil seeps into the lower level of a building. The water is directed by a sloping floor toward the pit, which is installed below the surface at the lowest section of the basement floor. In an industrial application, water moves into the pit as it leaks from pumps and other equipment, or is generated by washing down equipment and floors.

Most sump pumps have one of several types of level controls which signal the pump to start at a preset high level in the sump, and to shut off at a pre-set low level. The most common types of level switches are snap action, diaphragm, and tethered float switches.

Many of these systems use an electrically powered centrifugal pump. As the sump fills, the level control starts the motor, and the impeller turns, raising the velocity of the fluid and then converting this to high pressure in the pump volute casing.

Types of setups

There are two main types of sump pump setups—pedestal pumps, and submersible pumps. A pedestal setup, usually the less expensive option, has the motor mounted above the sump pit so that the motor is never submerged. With a submersible setup, the pump and motor are submerged in the sump pit, surrounded by a waterproof casing.

Here are a few sump pump manufacturers to consider.

Other related Pump Types include: water pumps, sewage pumps, submersible water pumps, well pumps.