By Vaishnavi Narasimhan
The Pallikaranai marsh is one of the last remaining ecosystems in Chennai. The marsh spread over 5000 hectares during the time of independence and has now been reduced to less than 600 hectares due to rapid urban expansion. Urban development in Chennai has historically gone hand in hand with reclaiming wetlands for waste disposal, housing and commercial and industrial purposes. Therefore, many water bodies associated with the Pallikaranai have been polluted and converted into waste water drains, resulting in a heavy loss of habitat.
The map below shows the various reasons for Pallikaranai’s shrinkage over the years. The Pallikaranai is bifurcated by the Tambaram Velachery Main road and the Pallavaram Radial road. Bifurcation has shrunk the marsh and also led to the loss of several species and habitat. The Chennai Corporation dump site is located on the northern side of the Pallavaram Radial road. Another dump site, used exclusively by Alandur Municipality is located on the eastern side of the Tambaram Velachery Main road. Apart from municipal solid waste, construction debris, tyres and untreated sewage water are all illegally disposed into the marsh. Infrastructure and construction projects such as the National Institute of Ocean Technology (NIOT), The Center for Wind Energy Technology (C-WET), the MRTS and construction of various IT company campuses on the banks of Pallikaranai have all contributed to the shrinkage of the marsh. Rapid urbanization over the past decade has resulted in congested residential areas near Pallikaranai and the rise of restaurants, shopping malls, skyscrapers, hospitals, and so forth, all weakening the ecological functions of the marshland.
The Pallikaranai marsh is important for several reasons. The marsh is connected to 31 different water bodies, all of which release surplus water into the marsh during the monsoons. Therefore, the marsh and its related water bodies are part of a system that is important for mitigation of flood waters. The marsh is also crucial for ground water recharge, soil and water conservation and lends itself as a grazing area and breeding ground for many species of fish and birds. Furthermore, it adds aesthetic, cultural and heritage value to the city. Our precious Pallikaranai is in great peril, unless immediate action is taken to stop dumping and other activities that will ultimately lead to the death of the marshland.
Reference: Chandramohan. D.B., Bharathi. D. The Role of Public Governance in Conservation of Urban Wetland System: A Study of Pallikaranai Marsh.