Sump pumps come in various sizes, and in most cases this isn’t the primary determining factor when you need a replacement. Sump pumps are designed to keep water off the basement floor and away from your foundation walls, where it could cause mold and mildew propagation, and foundation deterioration. Regional waterfall amounts and frequency determines how many gallons per hour you’ll need your pump to be able to push. The standard 1/3 horse power pump or a 110 volt pump will work for most spaces. There are even 1/4 and 1/2 horse power models, and size doesn’t determine power. Even small pumps can be adequate, pushing 3,000 gallons per hour. This should be enough for any basement.