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@article{206579,
        author = {Amrutha Rani H R and Yatish Ram, E. R and A. S. Ravikumar},
        title = {ASSESSMENT OF FLOOD INUNDATION USING HYDROLOGIC-HYDRAULIC MODELLING : A CASE STUDY FOR HEBBAL VALLEY, BENGALURU URBAN},
        journal = {International Journal of Innovative Research in Technology},
        year = {2026},
        volume = {13},
        number = {2},
        pages = {2500-2509},
        issn = {2349-6002},
        url = {https://ijirt.org/article?manuscript=206579},
        abstract = {Urban flooding has emerged as a major concern in rapidly growing cities due to increasing impervious surfaces, altered drainage patterns, and intense rainfall events. Accurate estimation of runoff and flood extent in an ungauged urban valleys are essential for effective flood management and infrastructure planning. The present study focuses on Hebbal valley located in the northern and northeastern regions of Bengaluru urban, Karnataka which is geographically lies between 12º 58’ and 13º 12’N latitude and 77º 31’ and 77º 47’E longitude and covering an area of 312.29 km². An integrated hydrologic and hydraulic modelling approach is adopted using HEC-HMS and HEC-RAS 2D to simulate flood scenarios under various return periods. The HEC-HMS model is used to simulate rainfall-runoff process using the SCS-CN method, incorporating rainfall depth from IDF curves, land use from Sentinel-2, soil data for infiltration, and SRTM DEM for topography. The output hydrographs are then input into HEC-RAS 2D to simulate spatial flood extents. Results reveal that the inundation areas expand significantly from 18.74 km² to 30.93 km² for the 2 year and 100 year respectively. The built-up zones being the most vulnerable to flooding, accounting about 43 % for 2 year event to increasing upto 57 % for 100 year event. This shift underscores the risk faced by urbanized regions during extreme hydrological events. The study demonstrates the integration of physically based models with geospatial datasets offers a reliable and scalable solution for flood risk assessment in urban ungauged valleys, supporting evidence-based urban flood mitigation strategies.},
        keywords = {Urban flooding, HECHMS, HECRAS, SCS CN, IDF},
        month = {July},
        }