Integrated Modelling of Rainfall Runoff Process and Rservoir Operation for balancing water supply and flood mitigation A case study from chennai India

Abstract

The water demand and the occurrence of hydrologic extremes in an newlineurbanized region have increased due to urbanization and climate change. The newlinereservoirs in the urbanized regions are utilized for providing solutions to the newlineincreasing water demand and hydrologic extremes. Researchers have studied newlinethe various impacts of reservoir operation on optimized use of water under newlinedifferent hydrological conditions using various algorithms and tools which newlinerequire large data and time. However, a simplified modelling approach for newlinereservoir operation is necessary to address the combined effects of floods and newlinedroughts. One such simple model for reservoir operation was developed and newlineintegrated with hydrologic and hydraulic models. The developed integrated newlinemodelling approach was used for the assessment of various operations of newlineChembarambakkam reservoir located in Chennai, India, and its impacts on newlinewater supply and flood mitigation. The rainfall variability and hydrometeorological newlinedrought in the Adyar River basin were analyzed from 1978 to newline2019 to understand the occurrence of hydrologic extreme events and their newlinerelationship with hydrological subsystems. The rainfall-runoff process in the newlinereservoir catchment and reservoir inflow was simulated using the Soil and newlineWater Assessment Tool. The model performance was ascertained with newlinemultiple performance indicators and found satisfactory. Further, this model newlinewas used for the simulation of reservoir inflow for the future period from newline2021 to 2099. This simulated reservoir inflow was used for the assessment of newlinewater supply management in the future period. The rainfall and reservoir newlineinflow were used as the inputs for developing the model for reservoir newlineoperation. newline