Designed and built a customised GIS application for the Drainage Services Department to derive the zone of influence (ZOI) which based on topology, slope orientation, drainage pipeline and manhole location. The ZOI represents the potential impact zone during leakage of drainage pipe on slope area. Automated map printing functionality was developed in ArcGIS to have auto batch publishing of the ZOI plan into survey extent map. The scope of work included over 4,500 numbers of slope area disseminated in different part of Hong Kong. Part of the services was to retrieve pipeline attribute information from the Intergraph Gtech AM/FM drainage pipeline network into GIS for auto reporting.