17.78% of Mumbai’s total 438 sq km. By 1992, the figure shot up to 246.16 sq km, or 50.96% of the total.
The phenomenal 216% increase in various kinds of construction over 66 short years has been correspondingly marked by a nearly 67% drop in the amount of open and reserved forest land combined and a nearly 19% drop in valuable wetlands, which include buffers like mangroves and mudflats.
The pace of urbanisation is so relentless that during five short years from 1987 to 1992, the amount of built-up land increased by 33 sq km. If one considers that urbanisation continued at that pace over the past 17 years-33 sq km every five years-then in 2009 we would have had at least 100 sq km more of built-up land than in 1992. That means at least 346 sq km of the city, or 79%, could be built-up today. With construction and development having moved at an increased pace over the past decade, the actual figure could be much higher. The analysis of maps showing development in the 2000s is still being done by IIT-Bombay professors, who have released the current data.
“The last five years have seen more concretisation. Built-up area has gone up at a tremendous environmental cost,” said A B Inamdar, a faculty member at the Centre of Studies in Resources Engineering.
Similarly, when satellite images of the city taken in 2006 are compared with pictures from 1997, it is apparent that the green cover left is being quickly lapped up by infrastructure projects as well as encroachment.
A research paper titled `Spatio-temporal analysis of urban land use in Greater Bombay region’, jointly written by IIT-B faculty members Smita Sengupta and P Venkatachalam, shows the shocking pace of environmental degradation. “This unabated urban sprawl has converted the natural landscape into an urban one on a wide scale,” said Venkatachalam.
The dramatic pace of falling green cover forced the Centre to pass the Forest Conservation Act, 1980, which resulted in an increase in reserved forest area from 44.85 sq km in 1962 to 62.81 sq km in 1987. What is however shocking is that this protected area also decreased to 58.17 sq km by 1992, which greens blame on encroachment.
Similarly, concretisation saw the death of large patches of mangroves. The city’s total wetlands fell from 105.56 sq km in 1926 to 85.58 sq km in 1992. A burning case in point is Manori Creek. From 1997 to 2006, buildings and resorts came up in green zones. Vidya Vaidya, of NGO CitiSpace, said, “We have systematically erased ecologically rich areas, like Manori, through land filling.”
Most shockingly, a 2005-06 estimate by the Mumbai chapter of the Mangrove Society of India says that wetlands today occupy a measly 10 to 12 sq km of land in Greater Mumbai. From 1997 to 2002, Mumbai lost close to 3,000 acres of mangrove cover due to “frenzied levels of land-grabbing”, said Rishi Aggarwal, of the mangrove society.
Nilesh Baxi, nominated member of the BMC’s Tree Authority, holds the toothless authority to blame for the loss of trees. “Every month 1,000 to 2,500 trees are permitted to be cut. Even the tree census shows shrubs and dead trees as trees,” he said.
Areas outlined in black are where greenery existed in 1997 but vanished by 2006. Greenery shows up as red in these satellite images
SEWRI
Reasons | Infrastructure projects, oil spills
Status | The Trans Harbour Link Project and projects like the Eastern Freeway threaten to cause huge disturbances to the ecosystem here, including the mudflats, which draw the flamingos annually. Greens say the area is losing greenery to residential projects. Gardens planted by builders will take years to reduce the carbon footprint.
VAKOLA-KALINA
Green cover lost | General vegetation, mangroves
Reasons | Airport expansion, university expansion, hotels
Status | Greens claim the Vakola-Kalina belt is becoming concretised faster than any other area in the city. The universitys expansion could have been vertical, greens say, but will now eat up a lot of vegetation. Private bungalows have also disappeared, giving way to corporate offices, industrial galas and residential projects.
Reasons | Resorts, illegal slums
Status | Greens blame a lot of the depletion in this ecologically rich area on illegal slums. They have proliferated even inside the protected areas, as shown by the brown spots inside the red zones. The development of resorts has also led to greenery being denuded. Ponds that exist because of wetlands are also dying.
Culprits | Road-widening, illegal cutting
Status | Green cover here has remained more or less constant since 1997, but the overall picture is not so rosy. The image only shows the southernmost tip of Colaba. Greens say there should be a tree for every five people, but south Mumbai doesnt even have a tree for every 10. Beautification schemes and high-rises without enough open spaces are also to blame.