PLANNING GREEN INFRASTRUCTURE STRATEGIES FOR URBAN HEAT ISLAND MITIGATION IN SHOLINGANALLUR, CHENNAI

Abstract

Rapid urbanization and infrastructure expansion along the Old Mahabalipuram Road (OMR) IT Corridor have significantly transformed the urban landscape of Sholinganallur, Chennai. The conversion of vegetation, wetlands, and open spaces into dense built-up areas has intensified the Urban Heat Island (UHI) effect, resulting in increased Land Surface Temperature (LST), environmental degradation, and declining urban thermal comfort. The proximity of the ecologically sensitive Pallikaranai Marsh further highlights the environmental vulnerability of the study area due to continuous encroachment and loss of natural ecological buffers. The present study aims to assess the spatial distribution and intensity of Urban Heat Island effects in Sholinganallur through Remote Sensing and Geographic Information System (GIS)-based analysis. The study examines the relationship between land-use transformation, vegetation loss, built-up expansion, and thermal variation using geospatial techniques. Satellite imagery was utilized to derive thematic layers such as Land Surface Temperature (LST), Land Use Land Cover (LULC), Normalized Difference Vegetation Index (NDVI), Normalized Difference Built-up Index (NDBI), and Normalized Difference Water Index (NDWI). Hotspot analysis was carried out to identify thermally vulnerable zones within the study area. The findings indicate that wards dominated by dense built-up development and impervious surfaces exhibit significantly higher surface temperatures, while areas containing vegetation, wetlands, and water bodies demonstrate relatively lower thermal intensity. The analysis establishes a strong relationship between increasing built-up density, declining vegetation cover, and rising surface temperatures. The study further identifies environmentally stressed wards such as Sholinganallur, Thoraipakkam, Pallikaranai, Palavakkam, Neelankarai, and Kottivakkam as priority zones for intervention. Based on the spatial analysis, the study proposes climate-responsive Green Infrastructure strategies including urban green corridors, roadside plantation buffers, shaded pedestrian pathways, green roofs, vertical greening systems, permeable pavements, blue-green infrastructure integration, and ecological restoration near wetland edges. These interventions aim to reduce heat accumulation, improve urban thermal comfort, strengthen ecological resilience, and promote sustainable urban development. The study contributes toward developing a spatial planning framework for Urban Heat Island mitigation in rapidly urbanizing metropolitan regions.