Rapid population growth, water and air pollution, overloaded public services, and traffic congestion can stress economies and result in unsustainable communities. Geographic Information Science (GIS) is a valuable technology for reversing negative these types of trends by identifying areas that may presently exhibit Smart Growth characteristics. Rather than expand on the current transportation infrastructure and develop new Smart Growth communities, San Diego Metropolitan’s Transit System (SDMTS) intends to use this study to review the current transit routing infrastructure in an effort to support communities exhibiting Smart Growth potential. Communities along existing transportation infrastructure will analyzed as potential Smart Growth and TOD communities. After the study is completed, SDMTS will have the geospatial data necessary for supporting future Smart Growth development