After the devastation caused by cyclone Aila in May 2009, the Centre has taken up a Rs 1,116-crore project to prepare an Integrated Coastal Zone Management Plan (ICZMP). For that, the World Bank has forwarded a loan of Rs 897crore. Recently, the Cabinet Committee on Economic Affairs (CCEA) gave its final approval for the initiative. A number of eminent geologists, marine biologists, botanists, oceanographers and economists will collaborate in the project and study in West Bengal, Orissa and Gujarat to evolve an integrated plan.
In West Bengal, scientists will take up an intensive study of the mangrove forest in Sundarbans to study its effectiveness in protecting the soil and embankment. The project will begin from September 2010 and will continue for five years.
Under this project, West Bengal has been given Rs 301 crore, Orissa Rs 201 crore and Gujarat Rs 286 crore. The state government will bear 10% of the cost. In West Bengal, the Institute of Environmental Studies and Wetland Management (IESWM) has been selected as the state project management unit. The IESWM has conducted a pilot study in Sagar Island, the data of which is being analysed. After that, it will take up similar studies in Sandeshkhali and Basanti, in September. According to Somnath Bhattacharya, deputy director of IESWM and a key person in driving this project, scientists have found that the mangrove forest has tremendous power in protecting embankment from tidal waves and soil erosion. Showing satellite pictures of Sagar Island taken in 1979, 1989 and 2003, Bhattacharya said, “It is observed that the areas where erosion has been halted and deposition of soil has begun at a big scale, the mangrove plantation has played a key role.”
He said that in the past the Sagar Island had dense mangrove forest. Citing the case of Maya Goalinir Ghat, a ferry point at the western coast of Sagar, Bhattacharya argued that till 1992, the area was suffering from steady erosion. The brick-pitched embankment could not stop erosion. Ever since the villagers took initiative to plant mangroves there, the erosion was halted and a steady deposition began.
The villagers now complain that sedimentation is forcing them to catch the boats after walking in the mud for some length. Similar trends have been observed in Naraharipur, Krishnanagar and Radhakrishnapur villages in Sagar where elderly villagers came forward to narrate their experience.
After Aila, the state government reported that of the 3,500 kilometer long embankments in Sundarbans, almost half had been destroyed. Talking about Aila caused destruction, Kanti Ganguly, the minister in charge of Sundarbans Affairs, told Business Standard that wherever there were some protective ring of mangrove forest, the embankments were saved.
More From This Section
But the brick-pitched embankments without any protective cover of mangrove were almost all destroyed. The scientists corroborate this by their observations that during the Tsunami in 2005, in a number of villages in Nagapattanam in Tamilnadu, The mangrove forest acted as a savior from the high waves. Bhattacharya points out that the mangrove serves three important purposes: 1) it stops erosion, 2) it encourages deposition of sediments, and 3) it works as effective shield against surge like high tidal waves.
According to scientists, every year the Ganga-Brahmaputra system carries 90,000 tonnes of sediments to its estuaries, which is the highest in the world. While a brick-pitched or concrete embankment cannot help create sedimentation or stop erosion, mangrove forest can entrap the fine particles (sediments).
The preliminary data encouraged scientists to study closely the efficacy of mangrove forests in protecting coastal zones. The initial response of the state government to the Aila had been to create concrete rings of embankment in Sundarbans. Now, with the backing of scientists, the government might find a long-lasting yet low cost answer to the problem.