Mapping impervious surface areas from GIS planimetric data

Urban impervious surface is a characteristic of urban development. Knowledge about the impervious surface area is an essential component of planning decisions at metropolitan areas around the world. This paper demonstrates the use of available GIS planimetric information in the production of an impervious surface area map of Hong Kong. Hong Kong is one of the most populous cities in the world where there is a continuous need for new buildings, roads and other infrastructure. Hong Kong's calculated impervious surface area constitutes 18 % of the total surface area of the Hong Kong territories, which makes the city one of the greenest of the world despite its high population. In this study potential challenges in the identification of impervious surfaces were investigated.