20230507 11241400 1.0 TRUE Stormwater Bills 2011 Gwinnett County Department of Water Resources, Stormwater Management. 2011 Stormwater Service Fee bills are based on the square feet amount of impervious area represented in parcel polygons. The impervious area polygons are created digitally by the evaluation of aerial photography using stereoscope equipment and proprietary software products. The impervious area polygons are intesected with the parcelnew shapefile, yielding a set of impervious polygons with a parcel ID number. The total impervious area for each parcel is summed and then the billable impervious area is rounded down to the next lowest 100 sq feet for billing purposes. The billing rate in 2011 was $2.46 per 100 sq ft. swservice@gwinnettcounty.com