Author(s): Subrahmanian Sreethu; Balaji Narasimhan; S. Murty Bhallamudi

Linked Author(s): Balaji Narasimhan, S. Murty Bhallamudi

Keywords: Low impact development techniques; Process modelling; HYDRUS 1D

Abstract: Increase in population and urbanization have been paving way for considerable variations in the hydrological cycles of our watersheds by altering the natural landscapes and processes. Increase in the frequency of occurrence of pluvial floods in urban areas can be regarded as an immediate effect of this hydrological change. For places where water scarcity prevails during the acute months, the flood water can be treated as an additional source of water (through storage and groundwater recharge) by integrating sustainable approach of low impact development (LID) techniques with storm water drainage systems. LIDs are primarily considered as runoff regulating structures and are effective when employed in plot level scales. However, the cumulative effect of LIDs implemented in watersheds, on runoff regulation as well as groundwater recharge, is an area less attended by research. LID process modelling for hydrological models which are capable of simulating large watersheds is hence imperative for analyzing the impact of LIDs in different combinations when implemented at a watershed scale. The objective of this study is to conceptualize different types of LIDs based on a simplified process-based approach integrating Green and Ampt infiltration model with nonlinear reservoir type model and verification of the same with process intensive HYDRUS 1D model, so as to enable its incorporation into hydrological models such as soil and water assessment tool (SWAT). This shall enable large-scale watershed scale impact assessment of LIDs on hydrological cycles in a less computational-intensive way. Successful demonstration of this may encourage policymakers to choose sustainable urban drainage systems over conventional drainage networks.

DOI: https://doi.org/10.1007/978-981-97-6009-1_8

Year: 2022