Why we need sump pumps
This picture shows a new basement before the final concrete is applied. Notice the accumulation of ground water because the sump pump system is not installed.
One of the most important functions of sump pumps is to protect basements from flooding. Heavy rains can overwhelm the sanitary sewer collection system and lead to sewage backups in basements. The sanitary system is designed to heavy rains, but it becomes overloaded because many people connect their sump pump discharge hose to the sanitary sewer. The sanitary system does not have capacity to carry this excess clear water.
Sump pumps also perform important functions during normal weather conditions. They drain groundwater from under and around our basement floors. Removing the groundwater reduces the possibility of the basement floors cracking and shifting from the water pressure. The basement area stays drier and feels less humid. Molds, mildew and other problems associated with damp areas will not get the opportunity to grow if the basement is kept dry and clean.