• Sudhakar B Sharma
• Dr. Anupam K Singh
• Dr. Ajay S Rajawat

Flooding has been considered as one of the most dangerous and costly disasters in terms of property damage and human casualties etc.. Flood mapping provides a better information to communities for a better flood risk management and it can help in controlling the damage by giving warning to concerned authorities. The Lower Tapi Basin (LTB) in western India having a geographical area of 2920 km2 has been experiencing periodic floods (1978, 1979, 1990, 1994, 1998 and 2006) those frequency has increased in the recent past. Therefore, flood probability, flood predictions, flood hazard and flood risk assessment area needed to do under flood management. In this research paper, Submergence area to be identified from the flood events was carried out for different return periods (i.e. 2, 5, 10, 25, 50 and 100 years) using the GIS-based 1-D hydrodynamic model from US Army Corps of Engineering- HEC-RAS and HEC-GeoRAS. Annual peak flow data of 30 years from 1978 to 2007 has been collected at Ghala station, which is in near Surat city and examine that maximum discharge 25778m3/s in 2006 and minimum 340.8m3/s in 1987. This research work is also compared six flood frequency distribution methods such as Extreme value type I distribution (EVI), Generalized extreme value distribution (GEV), Log-Normal distribution parameter two/three (LN2/LN3), Parson type III distribution (P3) and Log Parson type III distribution (LP3) for Ghala station on lower Tapi river. The existing methods of flood frequency analysis produce variable outcomes, particularly at the higher return periods. Under this research effort cross-section profile, stage-discharge rating curve, river profile, flood plain and Submerged mapping have been developed for deferent return periods such as 2, 5, 10, 25, 50 and 100 years using GIS and remote sensing data integrated HEC-RAS hydraulic model for lower Tapi basin from Ukai to Hazira. Steady Flow analysis executed in HEC-RAS indicated that the discharge of 1864, 5904, 11619,25634, 44176, and 73860 m3/s inundated 56.23, 80.51, 134.26, 234.73, 320.68 and 345 km2 area respectively. These results provide essential information for planners, administrators and strategy maker to analyze and manage flood hazard and reduce risk.

Flood frequency Flood modeling, GIS, HEC-RAS and Lower Tapi basin

"Flood Submergence Study Using an Integrated approach of GIS and Hydrodynamic Modeling for an Indian catchment", International Journal of Emerging Technologies and Innovative Research (www.jetir.org), ISSN:2349-5162, Vol.5, Issue 7, page no.638-652, July-2018, Available :http://www.jetir.org/papers/JETIR1807240.pdf

"Flood Submergence Study Using an Integrated approach of GIS and Hydrodynamic Modeling for an Indian catchment", International Journal of Emerging Technologies and Innovative Research (www.jetir.org | UGC and issn Approved), ISSN:2349-5162, Vol.5, Issue 7, page no. pp638-652, July-2018, Available at : http://www.jetir.org/papers/JETIR1807240.pdf