Faculty: Tushar Bose

Cost estimation of Low Impact Development Strategies

India is fast urbanizing. Between 2020 and 2050, India will add 416 million urban dwellers, more than any other country in this period (United Nations Department of Economic and Social Affairs Population Division, 2018). Urbanization brings challenges for cities in terms of stormwater management due to the change in natural hydrology in a city. This challenge is further exacerbated by climate change. As per the sixth IPCC assessment report, the frequency of 10-year floods is projected to increase by 1.5, 1.7, 2.7 times, and the intensity by 10.5%, 14%, and 30.2 %, for future global warming levels of 1.5 0C, 2 0C, and 4 0C, respectively (IPCC, 2021). This change in hydrology, coupled with the increasing frequency and intensity of extreme rainfall due to climate change, increases the flood risks in our cities.

One of the emerging areas that can enhance the adaptation of cities to flooding is the application of Low Impact Development (LID) strategies. LID refers to achieving natural hydrology " by use of site layout and integrated control measures" (Fletcher et al., 2015). LIDs are characterized by smaller-scale stormwater treatment devices such as bioretention systems, green roofs, and bioswales located at or near the source of runoff. In this research we will study the cost of implementation and maintenance of the Low Impact Development Strategies in the Indian context.