Indian urban regeneration with a Jane Jacobs formula

data science
urban morphology
buildings
jane jacobs
india
Author

Shrividya Ravi

Published

June 10, 2023

Over the last few decades urban sprawl has resulted in large scale losses of green space in the global south. In Mumbai, dense vegetation cover reduced by 50% in the recent three decades from 1988 - 2018 [1]. Sprawl also directly connects to the wellbeing of citizens - increasing their exposure to the rising consequences of climate change. Unchecked expansion of grey infrastructure without appropriate tree cover and green spaces results in poor resilience to extreme weather events - from urban heat islands that magnify temperatures to well above thermal comfort [2] and widespread flooding [3] during intense storm or monsoon downpours.

The myriad drivers of urban sprawl [4] include restrictive FSI (Floor Space Index a.k.a Floor Area Ratio, FAR) and other antiquated building regulations e.g. plot to building area ratios. In cities with low building area coverage and low FSI regulations, growth cannot happen in the more productive urban centre and is forced outwards.

Solid lines represent the urban area that has evolved without any maximum restriction on building height; dashed lines represent the urban area that has evolved with a maximum floor-to-area ratio of fifteen floors (horizontal dashed line in left panel). The vertical lines designate the boundaries of the area directly affected by the restriction. Figure and caption reproduced from [4].

Recent years have seen a flurry of regulation changes to increase the allowed FSI in urban areas. However, meaningfully improved urban development cannot be achieved by private, market-led development alone. It must be accompanied by investment in public infrastructure.

Indian cities usually lack good street network connectivity [5] [6] leaving them unable to cope with the expected increase in population and traffic volumes brought about by the FSI changes. Addressing this deficit needs more active management than just changing a number in the building code. During his recent step-by-step analysis of urban intervention in the Indian city of Ahmedabad, Dr. Bimal Patel [7] recommends three additional actions tp accompany an increase in FSI:

Dr. Patel refers to British colonial era covered arcades from Ballard Estate in Mumbai as inspiration for invigorating new developments with pedestrian movement. Photo credit Hemant Mishra /Mint. Sourced from Mint.

Though unmentioned, this plan exemplifies the four generators of urban vitality described by Jane Jacobs [9] [10].

Though Dr. Patel’s project is a design (rather than real life) example, there is hope that his pragmatic advice will catch on among Indian urban planners. With changes like this, Indian cities can hope for a higher quality of urban living than the unbridled urban development of the last few decades. However, the road to urban development in the global south has a long way to go. Urban regeneration must account for water, sanitation and electricity infrastructure as well as transit options, longer and safer pedestrian mobility, and resilience to extreme weather events.

References

[1]
S. Rahaman, S. Jahangir, M. S. Haque, R. Chen, and P. Kumar, “Spatio-temporal changes of green spaces and their impact on urban environment of Mumbai, India,” Environ Dev Sustain, vol. 23, no. 4, pp. 6481–6501, Apr. 2021, doi: 10.1007/s10668-020-00882-z.
[2]
B. Vinayak, H. S. Lee, S. Gedam, and R. Latha, “Impacts of future urbanization on urban microclimate and thermal comfort over the Mumbai metropolitan region, India,” Sustainable Cities and Society, vol. 79, p. 103703, Apr. 2022, doi: 10.1016/j.scs.2022.103703.
[3]
S. Paul, S. Ghosh, M. Mathew, A. Devanand, S. Karmakar, and D. Niyogi, “Increased Spatial Variability and Intensification of Extreme Monsoon Rainfall due to Urbanization,” Sci Rep, vol. 8, p. 3918, Mar. 2018, doi: 10.1038/s41598-018-22322-9.
[4]
“Causes and consequences of urban sprawl,” in Rethinking Urban Sprawl, OECD, 2018, pp. 113–142. doi: 10.1787/9789264189881-6-en.
[5]
C. Barrington-Leigh and A. Millard-Ball, “Global trends toward urban street-network sprawl,” Proc. Natl. Acad. Sci. U.S.A., vol. 117, no. 4, pp. 1941–1950, Jan. 2020, doi: 10.1073/pnas.1905232116.
[6]
I. com Jameela Ahmed, “Road test: Nine Indian cities among top 100 with worst street connectivity,” Feb. 27, 2020. https://scroll.in/article/954303/road-test-nine-indian-cities-among-top-100-for-worst-street-connectivity (accessed Jun. 11, 2023).
[7]
Session on Managing Urban Redevelopment by Dr. Bimal Patel, (Apr. 04, 2023). Accessed: May 20, 2023. [Online Video]. Available: https://www.youtube.com/watch?v=1cLROaiGJys
[8]
“Alain Bertaud, Bimal Patel, Vidyadhar Phatak on Improving Indian Urban Planning - YouTube.” https://www.youtube.com/ (accessed Aug. 06, 2022).
[9]
J. Jacobs, The death and life of great American cities, Vintage Books ed. New York: Vintage Books, 1992.
[10]
“Jane JacobsGenerators of Diversity.” https://blog.benchmarkurbanism.com/blog/computational-implementation (accessed Dec. 29, 2022).

Credits