High Spatial Resolution Land Cover, Percent Impervious Surface and Urban Tree Canopy derived by GEOBIA Techniques for Gainesville, GA

Abstract

Gainesville is located in Northeast Georgia in the outer suburbs of Atlanta and on the shores of Lake Sidney Lanier, which is the primary source of water for the metropolitan Atlanta area. A 6 inch spatial resolution land cover has been derived for the city of Gainesville using four band CIR aerial imagery and LiDAR. This land cover has been derived using Geographic Object Based Image Analysis (GEOBIA) techniques using rule-sets created on eCognition software. This high spatial land cover map of the city of Gainesville provides the basis for several value added products needed by city planners. The percent impervious surface per parcel has been estimated and forms the basis for a storm water utility tax that the cities in the region are considering implementing. The increasing impervious surface in the Lake Lanier watershed is starting to cause increased flooding and stream scour that can be ameliorated by better storm water utility infrastructure and this work provides preliminary estimates of the revenue that can be generated to this end for this study area. The urban tree canopy per parcel and for the entire city has also been estimated and this has implications for water treatment costs. Further modeling applications based on this GEOBIA derived land cover map will also be discussed.