Rainwater Harvesting for Urban Flood Mitigation: A BIM-GIS Integrated Approach

Abstract

Urban Flooding is becoming a major problem all around the world especially in developing countries like Pakistan, India, and Bangladesh etc. The common cause is the rapid Urbanization of major cities such as Islamabad, which is also our study area. Rainwater Harvesting has the potential to solve two problems of Islamabad, one is Urban Flooding, and the other is the rising Water Scarcity in the city. Rainwater Harvesting can help in collecting and storing rainwater from impervious surfaces thereby reducing runoff from surfaces and recharge the Groundwater. This research aims to evaluate the environmental, socio economic and operational benefits of integrating Building Information Modelling (BIM) Geographic Information System (GIS) Technologies for Urban Stormwater Management. Using high resolution spatial data and advanced modelling techniques, comprehensive analysis was performed for its impact and benefits to the environment. Our Research indicates reductions in water usage alongside better urban resilience against flooding and water scarcity. Our research suggests that even if <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$50 \%$</tex> of the rainwater in a year from surface runoff is harvested, CDA can supply the whole Islamabad with a sustainable source of water throughout the year. This research also compares our results with previous research, showcasing the advancements and the variations in Methodological and data usage. By demonstrating the Broad Benefits of BIM-GIS integration approach in Urban Water Management, this study emphasizes its potential to contribute to a greener and more sustainable urban environment for our upcoming generations.