-reduce the amount of water that flows into the storm sewer
-When the storm sewer gets overflowed it combines with the sanitary sewer and that water is not treated
-Rain gardens play an important role in that, carrying tremendous environmental and health benefits. They reduce toxins and other pollutants in water, turning streets greener and more resilient.
Rain gardens prevents sewage water overflow from going into treated water by taking in overflow water from the street.