eFADSS A Web GIS based Flood Awareness and Decision Support System for Pakistan

Abstract

Pakistan has been a target of catastrophic and frequent flood disasters over past many decades. Unfortunately the country has no effective system available for prediction and management of flood events despite their serious socio-economic consequences. The objectives of this study were to (1) develop an automated system for acquisition of near real time remotely sensed flood related data, (2) carry out post processing and analyses on the acquired spatial data for scenario based flood modeling and (3) set up a Web GIS based delivery system with Geospatial analysis tools and flood data dissemination mechanism to serve as a Flood Decision Support System for Pakistan. In the first phase of this study a number of remotely sensed near real time flood data sources were discovered which include NASA daily flood extents and Dartmouth Flood Observatory river discharge data. In the second phase various spatial analysis techniques were developed for the acquired data to establish flood hazard extents to provide spatial intelligence to decision makers. This included development of a Flood Vulnerability Model for spatial computation of vulnerable population and area based on anticipated flood extents. The vulnerability model was further refined using flood return period (4yr, Syr, 20yr, 50yr) extents developed using United Nations Environmental Program flood hazard data. An additional dimension was added in establishing flood hazard extents using Hydrologic Engineering Center River Analysis System (HEC-RAS) which involved modeling of complete Indus River Basin split into four reaches; Upper, Upper Middle, Lower Middle and Lower. Finally all of these capabilities and spatial products were packaged into an enterprise level web based delivery system based on ArcGIS server with a user friendly front end application and data dissemination mechanism developed using AP ACHE FLEX. The resulting Flood Awareness and Decision Support System has an independent data acquisition mechanism based on online remotely sensed data. The web based application provides users with efficient flood situational awareness along with state-of-the-art geo processing capabilities to extend necessary decision support. The resulting system in its present state is ready to be deployed and utilized by any disaster management organization of the country.