GIS Based Multicriteria Decision Analysis of Riverine Flooding: A Case Study of Maharashtra Deluge 2019

Abstract

Riverine flooding is frequent catastrophic event for Indian subcontinent and prevalent in western ghat region. The south-western monsoonal precipitation escalates the situation to detrimental level in the populous regions along the rivers. The previous studies suggest that the settlements in the vicinity of seasonal rivers are mostly affected during heavy precipitation due to unpredicted event and lack of preventive infrastructure along the bank. Such devastation can be reduced with detailed analysis of river basin and flood recurrence trends. Present study focuses on the flood frequency and settlement patterns in the Krishna River basin of Maharashtra state. The region has cotton soil (clay to loamy dark grey soil) cover, which encourages the agricultural practices. The agriculture being major occupation of the state engaged more than 64% population contributing largely in cotton and cereal production of the country. The discrete pattern of rainfall causes flooding at places, which not only distresses the settlement but also adversely affects the rate of soil erosion resulting elimination of the most fertile layer of surface. The study mainly emphases on the Shirindwad, Kurundwad, Rajapur villages of Shirol taluka of Kolhapur district, where Koyna, Warna, Panchaganga, Tarli, Urmodi, Dudhganga and Hiranyakeshi rivers of Krishna River basin overflowed decade’s water level in August 2019 flooding event. The event put an eternal scar to the inhabitants with pile of flood water over their cotton soil. The devastation of the event would be predicted if spatio-temporal analyses of rainfall and settlement pattern have been done. So, the present study aims to evaluate the impacts of future flooding by the analysis of rainfall pattern and demarcation of settlement clusters under threat. This can be done by scrutinizing ancillary data in GIS (geographical information system) environment with the help of temporal satellite data. The GIS-based multicriteria decision analysis can provide result as demarcation of potential flood risk zones and this can be resourceful for disaster management and town planning practices.