Urban Flood Risk Assessment Using Gis Based Hydraulic Modelling

Amongst the various techniques available for assessing flood risk, the ones using Geographical Information System (GIS) are most promising. GIS is used to construct and update hydraulic models which are capable of predicting one dimensional and two dimensional flooding. The paper evaluates a flood risk tool which uses two methods of risk assessment - backing up from connecting sewers and surface overland flow. Overland flows can be assessed in two ways - using a rolling ball technique and using two dimensional surface flow data from hydraulic simulation software. The paper concludes that ‘Flood Risk Tool’ which uses both the above methods is useful in understanding flood risk.