City’s built-up area rose 48% in two decades as the wider coastal stretch saw a 239% increase An aerial view of waterfront development between Marine Drive and Chathiyath Road in Kochi
The study examined land use and land cover changes along the coastal alluvial soil stretch (marine-origin soil found along coastal plains), covering 461 sqkm in Ernakulam and 1,222 sqkm in Alappuzha. Built-up area along the stretch has increased by 240%, from 109.93 sqkm in 2004 to 373.49 sqkm in 2024, largely at the expense of plantation, vegetation, wetland and agricultural land. Besides, the growing urbanisation will lead to intensified urban flooding as there won’t be enough permeable soil to pave way for the infiltration of water,” said Prof Girish Gopinath of Kufos, who was part of the study.
The finding is from a study jointly conducted by National Centre for Earth Science Studies, Kerala University of Fisheries and Ocean Studies, Sathyabama Institute of Science and Technology in Chennai and KTH Royal Institute of Technology in Sweden, which notes that high urbanisation in and around the corporation limits, such as North Paravoor, Tripunithura and Kalamassery, could pose a significant challenge to authorities and residents. It is causing a gradual decline of natural and semi-natural coastal land cover, which can accelerate coastal erosion and shoreline shifting and increase vulnerability to natural disasters, even resulting in habitat loss. The study also shows high urbanisation leads to declining vegetation and wetlands, alongside an increase in waterlogged areas. “Kochi Corporation emerges as the most urbanized, with its built-up area increasing… It is followed by urban centres such as Alappuzha, Mavelikkara, Kayamkulam, Ambalapuzha, Cherthala, Thrikkakara and North Paravoor. Such expansion of settlements, particularly along the coast, has resulted in large-scale encroachment of coastal land cover, intensifying ecosystem degradation and coastal vulnerability,” the study warns. “All existing buildings in Kochi are situated in wetland reclaimed lands. When the built-up area increases, there is possibility for soil subsidence in future.