The Sundarbans, the largest mangrove forest in the world, and the 70 lakhs people, animals, inhabit this island, and the environment are in dire straits. Especially Aila in 2009, Bulbul in 2019, super cyclone Amphan in 2020, and recently this year the very severe super cyclone Yaas slammed over Sundarban and flooded the villages, livelihood of people, animal dwellings and the rare Mangroves by breaching the river embankments. The frequent occurrences of the cyclones have imposed difficult situations on the entire ecosystem of Sundarban. We are trying to find out the solution to the problems. We can divide the entire discussion into four divisions:
The Current Problem:
Etiology and Study:
We know that when a river enters its estuary its speed gradually decreases. The sediments the river brings hurled on the riverbed. Particularly in the Sundarbans where small tributaries flow up to 3 to 5 meters of water during the high tide and run off at low tide. The silt carried during high tide is dumped in the riverbed as well as in the riverside. Although this system is very slow, over the years many rivers apparently lose their course and the riverside rise.
If we follow the above problems and their causes, we will realize that the root problem of Sundarban is the sediment issue. The silt carried by the river water is sometimes swallowing the river and sometimes the human habitat land is getting lower because of that silt. So, we have to find out the solutions of the sediment first.
3.Where the river has eroded human habitation and is creating river “chars” on the other side, if dredging can be done along the riverbank, then the course of the river will be forced to pass through that channel. The soil collected through dredging can be given for the repairing of the damaged islands. On one hand, there will be no need to acquire land for the construction of new ring dams; on the other hand, the course of the river can be controlled.
4. While making river embankments with a soil cutting machine, arrangements have to be made for good compression. Vetiver grass must be planted along the slope towards the river and two lines of mangrove trees called Geonwa should be planted in the bottom portion of the embankment where the tidal water comes. Cattle do not eat this plant nor it is handy for human use but grows in a very short time. The branches of the Geonwa tree will prevent the storm surges. In addition, mangrove trees should be planted up to a distance of 30 meters from the river.
5.On the man-inhabited islands, all roads after river embankments should be considered as backup embankments. If in any way the river embankment breaks and saline water enters, it should be confined to the land adjacent to the river. In case of an emergency, the nearest internal road should act as a second embankment, and the infrastructure should be built accordingly.
6.If we can collect the sediments on the riversides villagers can use them for the construction of houses and roads. This will allow the river silt to enter the islands artificially and the islands will be elevated. The process is called artificial sedimentation or siltation.
7. During the rainy season many times due to the heavy rain the excess water needs to be drained. With the water tons of sediments also flows back to the river. We have to make the villagers understand to wait for a while. After some days the slit will be set down, and then the water can be cleared. The slit will not go back to the river.
8. Many of the human inhabitant islands of Sundarbans had many small canals that were occupied for private ponds. Renovation of canals according to the old map will improve the drainage system. Otherwise, if for some reason the seawater or the rainwater confines, it will not be possible to get it out.
Outline of plan implementation:
We hope, the irrigation department of the Government will arrange for the removal of the silt from the riverbed. In this case, Government can take the help of the ocean experts or the experts working on the courses of the rivers. Silt and sand are more likely to remove from the riverbed, in which case we will encourage silt to be used for river dams and sand to be used by islanders. In all these processes, along with the use of machinery, it is necessary to take care of the employment of the common man. After the construction of the embankments, we can work with the forest department and local clubs or voluntary organizations to plant grass and mangroves on the embankment slopes. The implementation of the plan is equally important. Arrangements need to be made where, in addition to regular care; even minor problems can be dealt with as soon as possible so that a single problem does not lead to a major catastrophe. This monitoring team will monitor to prevent any illegal fishery in front of the river and to protect the mangrove forests beside the river. We are always ready to cooperate with the Government for the higher interest or development of Sundarban regarding the matter.