We know: All About Sump Pumps

What's a sump pump?

A sump is a low-lying place. A sump pump is the name for water pumps that are designed to help keep areas susceptible to flooding, such as basements, dry by allowing you to pump out excess water when it accumulates.

What kinds of sump pumps are there?

There are two kinds of sump pumps, electric-powered and water-powered.

Electric-powered sump pumps have two basic designs:

Upright or pedestal electric sump pumps have a motor positioned above the ground to avoid touching water. When water collects in the area around the pump, such as a basement floor, a float-activated switch rises and turns on the pump, which begins to drain the water. They are very effective, but can be noisy.

Submersible electric sump pumps can be placed directly into the ground where there is a drainage problem and are water-safe. A float-activated switch turns the pump on when it senses the presence of water. They often cost more than standing pumps, but are quieter and usually last longer.

Water-powered sump pumps also are activated by a float switch. They are powered by your home's water pressure pumping system and require no electricity, but you must have city water, not a well. They pump slower than electric models and are often used as a backup system for electric pumps.

What else should I look for in a sump pump?

Both kinds of pumps should always have a check valve to prevent water from flowing back into the sump or low-lying area when the pump is turned off.

How do I know what size to buy?

The size of the pump is determined by its horsepower. You determine the horsepower of the pump you need by considering things like the area of the sump, the depth of the groundwater, and how high you have to pump the water to remove it. For most homes, a 1/3 horsepower motor is suitable.

Typically, a 1/3 HP sump pump has an average lift ability of 25 feet and flow capacity of about 25 GPM.

Do sump pumps have filters which need to be cleaned or replaced?

Sump pumps do not have filters, but they do have screens or small openings where the water enters the pump. These can sometimes be plugged.

How much does a sump pump cost?

Sump pumps range in price from just over $50 to more than $500.