Danger Ahead! Ganga will become series of Stagnant Pools
Bharat Jhunjhunwala | 12.09.2014
A proposal to make a cascade of barrages from Allahabad to Haldia on the Ganga in under consideration of the Government. “Locks” will be made that will enable large 4500 ton ships to cross the barrages. It is told that the cost of transport by road is Rs 1.50 per kilo, by rail Rs 1.00 per kilo and by waterway Rs 0.50 per kilo. Movement of goods on the Ganga waterway will reduce the cost of transport and help push the growth rate.
The project will, however, impose huge environmental and cultural costs by converting free flowing Ganga into a series of reservoirs of 100 km length each. The ships will cross the barrage through locks but the fish will not be able to cross them. Many fish migrate long distances to their spawning grounds. The famous Hilsa mainly inhabits the sea. It migrates 1000 km upstream into the river to lays eggs. These eggs float down the river to the delta. Here they mature and fishes come out. These little fish go into the sea. Here they gain weight and again migrate upstream to lay eggs. This upstream migration has already been badly affected by the Farakka Barrage. The Hilsa was known to travel up to Allahabad previously. Now it can move only up to Farakka where its pathway is blocked by a stone wall. Despite Farakka, the Hilsa can presently move freely in the downstream from Haldia to Farakka; and in the upstream from Farakka to Allahabad. The proposed cascade of barrages will restrict movement of Hilsa to 100 km in the reservoirs. Hilsa will not be able to reach its spawning grounds. The fish may become extinct.
Fishes not only provide food for us. They also clean up the water. They eat the carcasses and twigs and other waste organic material. Thus we find large fishes merrily swimming in clear waters in holy places such as Shringeri in Karnataka. Extinction of the fishes will reduce, if not eliminate, this cleansing function and water quality will deteriorate.
The rivers also bring sediments. The Nagpur-based National Environment Engineering Research Institute (NEERI) has found that sediments of the Ganga contain high levels of Copper and Chromium. These metals have bactericidal qualities. The sediments also contain minute levels of radioactive thorium the functions of which are not understood as yet. The bactericidal qualities in waters of the Ganga is dependent on these Himalayan sediments reaching the lower stretches. These sediments will be trapped in the barrages and Ganga will be deprived of these beneficent qualities.
Another factor that imparts “self-purifying” qualities to the Ganga waters is the presence of wide-spectrum coliphages. The coliphages are beneficent bacteria while coliforms are harmful bacteria. Many hundreds of types of both are found in river waters. Normally one type of coliphage eats up one specific type of coliform. The specialty of the Ganga coliphages is that they are wide-spectrum. One coliphage eats up many types of coliforms. These coliphages stick to sand particles and remain dormant for long periods. They become active whenever they sense the presence of coliforms just as a sleeping person wakes up when he senses light. They impart “self-purification” quality to the water of the Ganga. Problem is that the sand particles on which the coliphages stick will not flow beyond Allahabad after making of the barrages. The Ganga will no longer self-purify itself in the lower stretches.
Trapping of the sediments will also impact the territory of India. The plains from Haridwar to Haldia have been formed by the sediments brought by the Ganga from the Himalayas. This heavy influx of sediments has counteracted the cutting action of the sea. The sea has a natural hunger for sediments. It east up the land to meet this hunger. Thus we find that most seashores are stony. However, large amounts of sediments have been flowing into the sea at the mouth of some rivers. These sediments have satisfied the hunger of the sea. That led to creation of new land. This process of land formation has been reversed after making of the Bhimgoda Barrage on the Ganga in 1850s and Tehri Dam and barrages at Chilla, Bijnor and Narora after Independence. As a result sediments are largely trapped and do not flow to the sea. The hunger of the sea is not satisfied and the sea has started cutting into the land of India to meet its needs. The Ganga Sagar Island has lost about three kilometers land in the last few decades. Making of the proposed barrages will accelerate this process and we may see much more of our sacred land going into the sea.
It is well known that sediments are piling up behind the Farakka Barrage. The depth of water behind the gates was about 75 feet earlier. Now it has been reduced to mere 15 feet. The Government of West Bengal has expressed fears that the Ganga may bypass the Farakka Barrage during a flood episode and wreck havoc to the areas on its banks.
The NDA-II Government had made an electoral promise to maintain aviral flow in the Ganga. Proponents of the Waterway are trying to wriggle out of this contradiction by redefining “aviral.” They are misinforming the people that releasing some water from the barrages continually will maintain “aviral” flow. It is not realized that even a release of 100 percent of the water from a barrage will not make it “aviral.” The water coming out fresh from the tube well is different that same amount of water coming out of a storage tank. There is no possibility of maintaining aviral flow after making the barrages. Therefore, this project would be a blatant reversal of the electoral pledge.
I am not against using the Ganga as a waterway. The way forward is to facilitate the movement of small ships not only up to Allahabad but up to Rishikesh. Need is to redesign Farakka, Kanpur, Narora, Bijnor, Haridwar and Chilla Barrages so that one stream of the river flows free and boats can ply on it. Water can be abstracted from the river for irrigation by making a partial obstruction and removing a part of the water as was done at Bhimgoda earlier. Other examples of abstraction of water without making a Barrage across the river are available from the old Tajewala Barrage on the Yamuna and on the Ruparel River in Alwar, Rajasthan.
People of the country hope that Prime Minister Narendra Modi will consider these various aspects and not be carried away by the bureaucrats who are often driven by commercial interests of shipping. Let us hope that green light will not be given to this horrendous project.
Author was formerly Professor of Economics at IIM Bengaluru
Author's phone: 85278-29777