Innovative water management using abandoned quarries for urban water supply and flood mitigation

Floods and droughts are becoming common and concurrently occurring in different parts of the world due to changing global climate. Innovative and sustainable water management strategies are necessary to overcome the issues of flooding and drought, especially in large urban regions. This study aims to use abandoned quarries as an innovative and sustainable measure for flood mitigation and improved urban water supply. Chennai, one of the large metropolises of India, is a typical example of a city experiencing periodic floods and droughts. The MIKE11 Nedbor-Afstromings Model (NAM) was used to assess the efficacy of the proposed intervention and temporally varying water diversion strategies among the different water storage options. The approach was also tested with extreme rainfall cases and flood events in 2015, and it was confirmed that the presented method would reduce the surplus flow in the river and improve the water supply. The approach considered here is promising as it is possible to increase the urban water supply and reduce the impact of flooding. The innovative approach has dual benefits and can be adopted in regions with abandoned quarries under changing climatic conditions, leading to frequent flooding and droughts.