Spatial BMP approach for mitigating the urban flooding in Bengaluru city, Karnataka, India

Abstract

Urbanization result into more impervious land cover and increased stormwater runoff leads to flooding of the drainage system. Best Management Practice (BMP) is an alternative approach to manage the urban stormwater runoff at the source where it originates. BMPs like permeable pavement, infiltration trench, bioretention cell, rainwater barrel storage and so on will be used to reduce rate of flow and flow volume. The present paper describes a simulation modeling approach to incorporate such BMPs in an existing hydrological model to estimate the performance of each BMP on runoff volume reduction under different rainfall characteristics. The results obtained are according to the suitable BMPs site availability in the study area. The BMP results are validated with the international stormwater management BMP database and results are comparable. The results indicate that, permeable pavement, infiltration trench, and rainwater barrel storage BMP scenarios are more effective than bioretention cell BMP scenarios in flood volume reduction under heavier and shorter rainfall events. This study provides information on BMPs implementation and its performance which is essential for urban flooding mitigation in the study area.