ABSTRACT
Cities are drivers of growth and development. They keep sprawling and expanding around the fringes to accommodate rapid urbanisation. In India, it is estimated that around 70% of the population will migrate from rural to urban areas by 2050. The peri-urban areas are the transitional zones where the urban and rural areas amalgamate. This study aims to understand the growth around the Indian metropolises of Delhi, Mumbai, and Kolkata that have transformed into megacities in the past few decades with a special focus on the sprawling regions of southern Chennai. The methodology adopted in this study includes spatio-temporal analysis of Landsat imagery and identification of sprawl directions through geospatial techniques using ArcGIS for the Chennai region. Secondary data including censuses, government reports, and master plans have been studied for the other metros. A comparative analysis between urban characteristics indicates that the urban agglomerations (UAs) in Delhi are moving towards vertical high-density settlements, UAs in Mumbai have low-density peripheral settlements, UAs in Kolkata have leap frog developments, while in Chennai, strip developments along transit corridors are visible. The unprecedented growth in the last decade has also led to mushrooming of haphazard settlements in these regions, creating strain on the available water resources and other infrastructure facilities. The study also indicates that in the southern region of Chennai UAs, there is an increase in green areas but depletion of water resources. Approximately 11.75 sq. km of water bodies were converted to land areas between 2011–2021. In Delhi, there has been an increase in urban areas by 70.24 sq. km and a decline in the rural areas by 27.76 sq. km between 2011–2015. This is due to the conversion of arable land into commercial, industrial, and residential land uses. In Mumbai, the major concerns are the rehabilitation of slums and informal settlements which also contributes to the city’s economy. The UAs of Kolkata have shown an increase in built-up areas of 9.9% and a decrease in agricultural land of 6.35%. This indicates a primary shift in occupations from agriculture to other types. Some intrusions into ecologically sensitive areas and loss of forest cover can also be attributed to these sprawl conditions. There is a growing concern about solid waste disposal, waste management, and the locations of landfills that could impose a threat to the living conditions of the people in these fringe developments. A deeper probe using geospatial techniques would allow planners and decision-makers to design sustainable solutions in the ever-expanding peri-urban regions.
