Author(s): P. Vengadesan; S. A. Sannasiraj; S. Murty Bhallamudi

Linked Author(s): Sannasi Annamalaisamy Sannasiraj, S. Murty Bhallamudi

Keywords: Narmada river; Estuary model; Tidal dynamics; River discharge control

Abstract: Estuaries are transitional zones between the river and the marine environment and one of the most productive ecosystems in the world because they are home to a wide variety of species. The estuarian environment is very complex due to the influence of waves, tides, river flow and human interventions. The tidal wave propagation from oceans to coasts and estuaries are modified by shallow water friction, basin topography and river discharge. The fresh water discharge and the tidal characteristics are the external forcing factors that affect the estuarian dynamics. Dams prevent water scarcity in non-monsoon periods, but the seasonal flow patterns are severely impacted. Especially the frequency and characteristics of floods on the downstream side get affected. The river discharge reduces the tidal motion by damping and dissipating the energy. So, the hydrodynamic conditions of a particular site are often affected by variation in fresh water input into the estuary and the tidal amplitude variation at the river mouth. For the proper functioning of the estuary, the freshwater inflow is very much essential. In this study, the impact on the Narmada River estuary due to discharge reduction by Sardar Sarovar Dam is investigated using TELEMAC-2D numerical model and extent of tidal intrusion for various discharge rates and tidal conditions along with tidal propagation characteristics in the Narmada estuary is evaluated.

DOI: https://doi.org/10.1007/978-981-97-6009-1_29

Year: 2022