Water from rain and melting snow that does not immediately soak into the ground is stormwater runoff.  Stormwater flows across impervious surfaces such as concrete, streets, roofs, parking lots and sidewalks into catch basins, storm drains, swales, culverts, ditches and drywells, eventually emptying into our Lake and aquifer. Stormwater can carry pollutants, like lawn chemicals, automobile oil, grease, pet waste and sediment to our lakes and rivers.