Mushrooming of unauthorized huts in or around the mangroves of Mumbai is posing problems of urban sanitation and coastal cum marine ecology jeopardizing the natural health of these shrubs and trees that act as natural walls against floods during the monsoon.
The Urban Design Research Institution (UDRI) has expressed very serious concerns about the dumping of garbage, construction site debris and effluences of industries into the mangroves. All mangroves in Municipal Corporation of Greater Mumbai (MCGM) are suffering from siltation problems and small islands also have emerged in them due to obstructions in the flow of water.
There are about 3,998 hectares of mangroves spread over Mumbai. Nearly 32.85% mangroves have already vanished in Mumbai since the urban sprawl of 1985-86. Between 2000 and 2012, satellite images were taken of the mangroves.
At Shirgaon, the flow of tidal waters was hindered due to ecological problems. This caused widespread damage to mangroves spread over 75 hectares of land. The “photographic differences of mangrove cover” shows that nearly 108 mangrove patches in the Lagvan–Kasari–Satkondi along the Jaigad creek either vanished or shrunk dangerously.
Nearly 50% Mumbai’s mangroves destroyed since 1992 due to their urban abuse like parking cars in the mangroves, building huts by migrant labourers, pumping of toxic industrial waste, dumping of MSW and construction industry debris.
A large number of mangroves in Malwani, Dahisar, Govandi, Bhandup Vasai, Esselworld, Oshiwara, Ghansoli, Kanjurmarg, Kanakia Nagar in Mira Road, Ghatkopar, Mulind, Chembur, Kasheli in Thane and Palm Beach Road between Vashi to CBD Belapur in Navi Mumbai have been destroyed due to coming up of huts and dumping of urban waste.
Mangroves, very sensitive to ecological conditions and polluted air, cannot grow if the carbon’s ratio is very high in the marshy soil. Due to dumping of waste and toxic elements, the wetlands are turning very highly carbonized thus hindering their growth. In Sewry Bay, a large numbers of mangroves died/dried up due to excessive carbon particles in the wetlands.
The soil testing and chemical analysis of the marshes showed that the pH value of the soil in Sewry Bay was 6.3. that meant that the soil had turned highly acidic. If sulphur/alkali/acid content grows, mangroves cannot survive. If wetlands get hardened due to alkalinity or acidity, mangroves will die.