Flood Modelling and Mapping

Abstract

This chapter presents an overview of the important concepts related to flood hazard assessments and explores the use of remote sensing data from satellites to supplement traditional assessment techniques. The method presented in this chapter can be used in sectoral planning activities and integrated planning studies and for damage assessment. The chapter presents the application of flood modelling to the study area. The study area, Adyar River in Chennai, has experienced major floods in the past decade which is attributed to increased urbanization. The hydrologic model for the Adyar River Basin was set up using HEC geoHMS and was run and calibrated using observed flow in HEC-HMS. The chapter also discusses the results obtained from the IDF analysis and its application in HEC HMS to generate hypothetical storm hydrographs. Furthermore, the chapter goes on to discuss the results obtained from the hydraulic modelling such as the inundation map for the 2005 flood event and the inundation map for hypothetical storms of varying return periods.