On the shifting banks of the Ganga in West Bengal

Published
21st Jan, 2023

Context

The Continuous shifting plains of River Ganga in West Bengal is creating difficulties for locals to maintain their livelihood and is a cause of concern which needs a view to curb the menaces.

About

About the Ganga’s regime in West Bengal:

The mighty river enters the West Bengal plains from Rajmahal hills of Jharkhand’s Sahebganj district after a long journey of about 2,000 km from the Himalayas as it begins to break away into distributaries.
The Ganga divides into two major distributaries, Padma and Bhagirathi-Hooghly, at Mithipur in Murshidabad district.
The Padma carries the bulk of the discharge, flows about 65 km along the India-Bangladesh border, and finally leaves Indian Territory at Jalangi.

The River Ganga:

The National River of India Ganga flows through India and Bangladesh.
The river flows through the Himalayas, Gangetic plains and empties into the Bay of Bengal.
In Indian traditions and culture, river Ganga is personified as Goddess Ganga.
It is a revered belief that to remit sins, one has to take a dip in river Ganga. It further channelizes the salvation, so is believed in Indian culture.
A Siamese festival called ‘Loy Krathong’ of Thailand includes a tradition of floating candles into the waterways praying to Goddess Ganga.
Hindus consider the Ganga River the holiest of all the rivers.
Ganga is also mentioned in one of the four Vedas – Rigveda
Various reptiles and mammals find their habitat in the Ganga river:
- Gharial
- National Aquatic Animal of India – Gangetic River Dolphin
- The river starts from the Gangotri Glacier in the name of Bhagirathi river
Ghagra River is the largest tributary of river Ganga
Mainly the Sediment-laden flows of Ganga with the Brahmaputra River form Ganges Delta which is the world’s largest delta.

The reasons for shifting plains:

Due to Erosion and Deposition in a Meandering River: As Ganga reaches in it Old Stage till reaching West Bengal, it shows features of a meandering river.
A meandering stream has a single channel those winds snakelike through its valley.
As water flows around these curves, the outer edge of water is moving faster than the inner.
This creates an erosional surface on the outer edge (a cut bank) and a depositional surface on the inner edge (a point bar). Where the bends of two meanders meet, they bypass the curve of river, creating an oxbow lake which may then be in filled with overwash sediment.
Due to high disposal of water: As the region is evident for many rivers and tributaries adding water to the Ganga, it changes its course frequently to left out the load of deposits it carried way long.

Impacts:

Loss of livelihood for locals dependent on the land and water.
Fear of floods during monsoon season.
Loss of biodiversity like insects, plants etc.

Challenges:

Development projects like barrages, Dams etc. can affect the River regime in the region and further deteriorate the condition.
Sand mining and Human activities is affecting the changing course of rivers and also effect biodiversity.