As a wildlife biologist, it has been my good fortune to explore and experience the forests of India from Siachen to the Andaman Islands and Kutch to Arunachal Pradesh. The diversity of forest types and the wide variety of creatures that inhabit therein has never failed to humble me. Having surveyed, studied and documented the wildlife of these amazing forests, every visit back to the Sanjay Gandhi National Park (SGNP) made me realise that this suburban jewel is a boon to Mumbaikars.
In barely 104 square kilometre, the SGNP harbours over 274 species of birds , 170 species of butterflies , 35 species of mammals, including over 35 leopards — the highest density even compared to Tiger Reserves — 78 species of reptiles and amphibians, over 90 species of spiders and 1,300 species of plants. The forests of the park are catchment to the lakes of Vihar and Tulsi, which provide nearly 10 per cent of Mumbai’s drinking water.
In a shocking revelation, the MSRDC is planning to tunnel a road connecting Borivali to Thane, passing right under the SGNP, ignoring not only an Archaeological Heritage Site of Kanheri Caves but also an important Natural Heritage site protecting rare species representative of the Western Ghats. The report is misinforming about the special geological formations of the region. It has proposed to tunnel in thickest lava flow of Amygdaloidal Basalt which is absolutely watertight, having good quality compressive strength and easy to excavate. In reality the ridges of Kanheri Caves region are basaltic in nature with intervening ash beds. A fascinating geological feature ‘Volcanic agglomerate’, which is made up of sub-angular vesicular bombs and volcanic ejecta set in a matrix of amorphous. Drilling in this region will affect the ground water and reduce the catchment capacity of both the lakes, forcing Mumbai into a water-dependent city.
Oversimplistic statements like “flora and fauna will not be affected” and false promises of reduced travel time don’t take into consideration the hydrology and special geology of the region. The tunnel will break many hardpans and will definitely affect both surface water holding capacity and hence the forests that stand above it and the streamflow and seasonal and perennial waterbodies. In the long run this project is going to destroy the green cover and quality of life of Mumbai.
(The writer is an environmentalist and founder of Sprouts)
