Potential of Retrofitting Sustainable Urban Drainage Systems Using an Integrated Geographical Information System-Remote Sensing Based Approach

Many urban areas are located in flat, low lying coastal areas with outdated, inadequate sewer networks. Flooding is a major problem in such urban areas worldwide with consequent severe economic impacts. Many current monitoring approaches are based on ground-based visual mapping and household flooding surveys which are expensive, time-consuming and often produce inaccurate and spatially incomplete results. Low-cost methodologies that can rapidly assess the scale and identify the reasons causing these flood events at minimal cost are therefore urgently required. This study has evaluated the capability of an integrated remote sensing and geographical information system based approach to provide complete coverage of the critical information on the spatial extent of flooding and flood water volumes rapidly and at low cost. Airborne and Terrestrial LiDAR datasets were combined with digital aerial photography, flood assessment surveys, and maps of housing, infrastructure and the sewer network to provide an enhanced understanding of the sources and pathways of the flood water runoff, accurate quantification of the water volumes associated with each flooding event and the identification of locations and size of potential retrofit Sustainable Urban Drainage systems.