A water-powered sump pump is a type of sump pump that uses the pressure of your home's water supply to pump water out of the sump pit. . They're typically used as backup pumps in case of a power outage. Instead of using electricity, water-powered pumps use a venturi system that creates a vacuum to draw water up from the sump pit.. They're also environmentally friendly, as they don't use any electricity. However, they can use a significant amount of water, so you may see an increase in your water bill. They also require a continuous and sufficient municipal water supply to function effectively. .