Real-time flood forecasting using an integrated hydrologic and hydraulic model for the Vamsadhara and Nagavali basins, Eastern India

• Published in: Natural hazards (Dordrecht) Vol. 120; no. 7; pp. 6011 - 6039
• Main Authors: Venkata Rao, G., Nagireddy, Nageswara Reddy, Keesara, Venkata Reddy, Sridhar, Venkataramana, Srinivasan, Raghavan, Umamahesh, N. V., Pratap, Deva
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.05.2024; Springer Nature B.V
• Subjects: Agricultural land; Basins; Civil Engineering; Cyclones; Depth; Earth and Environmental Science; Earth Sciences; Environmental Management; Extreme weather; Flood forecasting; Flood frequency; Flood predictions; Flooding; Floods; Geophysics/Geodesy; Geotechnical Engineering & Applied Earth Sciences; Government agencies; Historic floods; Hurricanes; Hydraulic models; Hydrogeology; Hydrologic analysis; Hydrologic models; Lead time; Modelling; Natural Hazards; Original Paper; Precipitation; Rainfall; Rainfall forecasting; Soil water; Stream discharge; Stream flow; Tropical cyclones; Two dimensional analysis; India; Lead time; SWAT; Integrated model; GFS; HEC-RAS; Flood inundation area and depth; Floods
• ISSN: 0921-030X; 1573-0840
• DOI: 10.1007/s11069-023-06366-3

Due to recent rainfall extremes and tropical cyclones that form over the Bay of Bengal during the pre- and post-monsoon seasons, the Nagavali and Vamsadhara basins in India experience frequent floods, causing significant loss of human life and damage to agricultural lands and infrastructure. This study provides an integrated hydrologic and hydraulic modeling system that is based on the Soil and Water Assessment Tool model and the 2-Dimensional Hydrological Engineering Centre-River Analysis System, which simulates floods using Global Forecasting System rainfall forecasts with a 48-h lead time. The integrated model was used to simulate the streamflow, flood area extent, and depth for the historical flood events (i.e., 1991–2018) with peak discharges of 1200 m 3 /s in the Nagavali basin and 1360 m 3 /s in the Vamsadhara basin. The integrated model predicted flood inundation depths that were in good agreement with observed inundation depths provided by the Central Water Commission. The inundation maps generated by the integrated modeling system with a 48-h lead time for tropical cyclone Titli demonstrated an accuracy of more than 75%. The insights gained from this study will help the public and government agencies make better decisions and deal with floods.