Assessing the benefits of Blue-Green Infrastructure for Pune

Abstract

As cities sprawl and populations surge, urban environments face a double threat. Rapid development strains resources like water and sewage systems, while the loss of green spaces due to construction exacerbates flooding. Impervious surfaces like roads and buildings prevent natural water absorption, overloading storm water drainage. Blue-Green infrastructure (BGI), encompassing elements like parks, rain gardens, and street trees, emerges as a promising solution. These features not only mitigate flooding but also enhance urban living. However, a significant gap exists between developed nations with extensive green spaces and many Indian cities. While urban planning in India designates open spaces, the actual implementation often lags, leaving cities vulnerable and lacking the benefits of a robust green infrastructure. This thesis explores the challenges and opportunities associated with green infrastructure development in Indian cities, aiming to bridge this gap and create more sustainable and resilient urban environments. Despite the important role of BGIs, a comprehensive synthesis of the quantification of their full range of benefits and challenges is lacking in the current literature. To address this gap, a systematic literature review and analysis needs to be conducted on the quantifiable environmental, economic, and social benefits of BGIs. While several cities have begun to explore BGI within their own municipal infrastructure programs, but there is no general method for evaluating the benefits present. The aim of this thesis is ‘To achieve widespread adoption of blue-green infrastructure by making community participation central to its implementation in the urban landscape of Pune.’ The objectives are as follows: Literature review of various toolkits available for valuation of Blue-green Infrastructure. Valuation of existing blue-green infrastructure within the selected study watersheds of Pune. Assessing the benefits of Blue-Green Infrastructure for Pune Department of Transport Planning, School of Planning and Architecture, Bhopal (MP)-462030 vi Provide solutions as to how to implement blue-green infrastructure in a city like Pune for the purpose of mitigation of climate change impacts through community participation. Limitations include the following: Multiple benefits: BGIs provide a wide range of benefits, making it difficult to quantify their total value. Intangible benefits: Many BGI benefits, such as improved quality of life, are intangible and difficult to measure in monetary terms. Data scarcity: Reliable data on the costs and benefits of BGI projects is often limited. This thesis investigates the effectiveness of blue-green infrastructure (BGI) in Pune. Employing a mixed-methods approach, the research combines quantitative data analysis of existing flood records, groundwater levels, green space, and impervious surface ratio, etc along with qualitative interviews with urban planning officials and residents. Analysis to quantify the benefits include selecting suitable watersheds within Pune municipal boundary and comparing and analysing them based on change in land use and land cover, ecosystem service valuation analysis, SCS-CN, performance of levels in groundwater monitoring wells over last 20 years, existing interventions of BGI and using the ‘InVEST’ toolkit. This will thus result in developing a spatial analysis to identify areas in Pune that would benefit most from BGI implementation, considering factors like flood risk, existing green spaces, and population density and recommend specific types and configurations of BGI for different urban settings within Pune.