A sump pump pumps ground water (water from the soil/drain tile surrounding your home’s foundation). When the sump pump activates, it pumps the water out of the sump basin through a discharge pipe out onto the lawn or a municipal storm sewer.
An ejector pump moves wastewater up into the main sewer line. Homes that have bathrooms and/or water-using appliances installed in the basement or lower-level need an ejector pump. Because these fixtures are lower than the home’s main sewer line, wastewater cannot flow out utilizing gravity – therefore a pump is needed to pump it up and out of the home.
The main difference between a sump pump and an ejector pump is the presence of sewage. Ejector pump failure can cause raw sewage to enter your basement. Sump pump failure causes flooding and water damage.