A stormwater fee (or stormwater utility fee) is a charge to property owners for managing rainwater runoff, typically based on the amount of impervious surface (roofs, driveways, parking lots) on the property rather than property value or water consumption. Stormwater fees fund storm sewer systems, drainage infrastructure, flood management, and increasingly, water quality improvements. Separating stormwater costs from general taxes or water rates makes the costs transparent and allocates them based on contribution to runoff. Properties with more impervious surfaces creating more runoff pay more. Some programs offer credits for on-site stormwater management like rain gardens or permeable paving. Stormwater utilities are becoming more common as municipalities invest in aging drainage infrastructure and water quality improvements.