The fragile ecology of the Sundarbans delta, which is home to four million people and the Royal Bengal Tiger, is now facing a fresh threat from large-scale construction of concrete embankments all over the islands, environmentalists have warned.
Doubting the feasibility of these embankments as coastal erosion is constantly re-shaping the islands, WWF’s Anurag Danda said the engineering intervention will prove detrimental to the survival of the unique flora and fauna of the UNESCO World Heritage site.
The archipelago of over 100 islands, a three-hour drive from Kolkata, is a complex network of streams, rivers, tidal creeks and channels. Spread over an area of 9,630 sq. km in India, Sundarbans has the world’s largest mangrove forest and also hosts a tiger reserve and three wildlife sanctuaries.
To protect the islanders from the cycle of twice-a-day floods and cyclonic storm surges, the West Bengal Government has started the embankment reconstruction project to protect about 3,500 km of boundary at a whopping expenditure of Rs 5,032 crore.
“The ecology of the Sundarbans will get affected as the engineering interventions are not done keeping in mind the ecological realities of the area,” Jayanta Bandyopadhyay, head of the Centre for Development and Environment Policy at IIM Calcutta , told PTI .
Sundarbans expert Tushar Kanjilal, who was honoured with a Padma Shri for his work in the region, complained that an Environment Impact Assessment (EIA) report had not been prepared before implementing the project.
Besides being a habitat for a number of species of kingfishers, a whole variety of flora and fauna survives on the banks of the group of islands, half of which have human habitations.
“There will be zero flora in the area once you concretise that space. Even birds occupy those portions of the banks which don’t get inundated,” said Danda, head of the Sundarbans and Climate Adaptation programme of WWF-India.
Pointing out that crabs were the tillers of the land in a mangrove ecosystem, Danda said their habitat too would be lost with the construction of concrete embankments. Nutrient recycling, essential for the growth of mangroves and other trees, would also be hampered, and affect soil fertility.
Eminent environmentalist Ashish Kumar Ghosh pointed out that the technology being used in the embankment had not been tested. “We can’t play with nature and do a trial and error method on such a large scale,” he said, adding that the currents and tides flowing all around the islands were too powerful to let embankments last longer.
Experts also warn that covering the riverside slope of the embankment with polypropylene sheets, a non-biodegradable material, would violate environmental standards.
Concrete embankments have earlier proved failure in the Sundarbans. Danda recalls that he has twice seen such structures getting washed away at Moushuni island.
Sugata Hazra, director of the School of Oceanographic Studies at Jadavpur University, estimates in his research report that in the last 30 years approximately 7,000 people have been displaced as an average of 5.5 sq. km of land has been eroding away each year in the delta due to climate change and other factors.