Flood monitoring using microwave remote sensing in a part of Nuna river basin, Odisha, India

Floods adversely affect the life of people and property in the coastal districts. It is important to delineate the flood extent and pattern which helps in the vulnerability assessment and also to find out the intensity of damages to facilitate future planning and management. The study area is a part of the Nuna river basin, which suffers from the flood disasters frequently. The present study applies microwave remote sensing (RADARSAT-1 images) to monitor extent, depth and duration of 2003 and 2008 floods in the Kendrapara district of Odisha, India. RADARSAT-1 images of 4, 11, 13 and 20 September of 2003 and 18, 20, 22 and 24 September of 2008 were used to monitor the flood extent, duration and depth. The threshold method was used to delineate flood extent which was used for calculating flood duration and depth. Further, vulnerability assessment of the paddy crop was done to obtain intensity of damage in the area from the 2003 and 2008 floods. Field survey was done to verify and assess the generated results. Areas affected by more than 15 days of flood duration and depth of more than 3 m faced maximum loss. Both the years witnessed major floods in this area with an estimated damage of around INR 174 million ($3.6 million) in 2003 and INR 75 million ($1.6 million) in 2008.