The impervious cover data is generated using aerial photography collected every two years. Each pixel on the aerial photography represents 6 inches on the ground. The accuracy is suitable for defining the edges of buildings, patios, driveways and other types of impervious cover. This data was used to create impervious cover maps seen on the Find My Drainage Charge Map Tool. (For best results, use Internet Explorer 9 or higher, Firefox, Google Chrome or Safari.)
For properties developed or modified after the latest aerial photography, we use building permit data. Bills are typically adjusted based on the latest aerial photography in February during odd-numbered years.
