Hydrodynamic flow modelling and effect of roughness on river stage forecasting

Abstract

In recent times, undesirable climatic conditions have been attributed to climate change. The intensity of rainfall has amplified extremely, causing floods in many areas worldwide. It is desirable to regulate and minimize the consequences of floods and excess downpour. Using geospatial data for the development of hydraulic models and mapping of simulation results has become standard practice for floodplain assessment. The objective of the current investigation is to use one-dimensional floodplain modeling of the Bhima River between Lonikand and Rahu using the RAS-mapper tool (HEC-RAS). The modeled river reach is about 67 km long, near the Pune administrative division of Maharashtra, India. The hydrodynamic flow computations were carried out for the years 2005 and 2017. A total of 595 cross sections along the main river was employed for hydrodynamic flow simulations. In this study, cross-sections and past observed flood data have been used to develop a 1-D integrated hydraulic model of the Bhima River. The simulated water levels are also validated with observed water levels and found to be reasonably correlated.