West Seti dam will worsen flooding in Nepal

A B Thapa

India’s proposed link canal plan is a subject of considerable debate in Nepal. Various NGOs and other institutions have spared no effort and money in holding meetings to discuss the long-term adverse effect of such plan. Unfortunately, none of the NGOs have cared to speak for the people in western Terai, who have already started to suffer from flooding caused by India’s 230 km long Saryu link canal running from west to east parallel to Nepal-India border. The canal, which is still under construction, is sure to worsen the flooding situation in Nepal to an unbelievable extent once it goes into full operation. The technical details of the canal have been presented in such a simplified form that even people without engineering background can easily understand. There is no doubt that the proposed West Seti storage dam is the root of the western Terai submersion problem because the Saryu canal is totally dependant on the regulated flow from the West Seti reservoir.

The irony is that while the NGOs, intellectuals, politicians and media are occupied in denouncing India’s vague plan to link rivers that could have negative impact in the long run on water balance of downstream country. They seem hardly concerned for the desperate plight of a large number of Nepalis in the western Terai already becoming homeless as a result of the construction of the Saryu link canal. This canal has been planned to draw the regulated flow of the West Seti and the Karnali rivers. As a result, the activities of NGOs are helping divert the attention away from the West Seti project related flood problems. The funniest thing is that it is not India that is pushing the West Seti project. Regrettably, Nepal is doing its level best to implement the West Seti project that would result in submersion of a vast area of lands in western Terai along the Indian border. Nepal has already given green signal to a private developer to implement the West Seti project without settling the difference with India on the western Terai submersion problem.

There are two irrigation canals taking off from the Girjapur barrage already built in India across the Karnali river. On the left is the

Saryu Canal running to the east beyond the Banganga river and on the right is the Link Canal connected with the Sarda Sahayak canal planned to irrigate about 2 million ha. At

present only the right bank canal is operational because the dry season flow of the Karnali

river is quite insufficient for both the canals and there are technical difficulties to utilise the

river’s monsoon flow. The year round operation of the Saryu Canal depends entirely on availability of the regulated flow from the proposed storage reservoirs in Nepal.

Normally siphons are provided to deliver canal water across a river. This type of river crossings does not hinder the river flow. In case of the Saryu Canal, altogether a different type of river crossing structure has been devised. Barrages have been built across the rivers to elevate the river water to such a level that would allow free passage of canal water across the river into the canal taking off from the other side of the river. The contentious Laxmanpur barrage is one of such structures devised to deliver the water from the Girjapur barrage across the West Rapti river.

It would be necessary to maintain all the time pond water upstream of the barrage above certain fixed level to keep the Saryu Canal running at desired capacity. Since the pond would always be full, a sizeable area in Nepal could remain perpetually submerged. When the river is flooded, the water would be spreading out onto the lands that were never before regarded prone to flooding. The canal is expected to cross innumerable small rivers and drains on its way. Embankments and dikes, which will be needed to train these drains and rivers to protect the canal, could also result in widespread flooding in Nepal.

After implementing the West Seti project exclusively for power generation, Nepal would forfeit for ever an opportunity to share with India downstream benefits accruing to them from irrigation development in their territory. Nepal is thus on the verge of providing West Seti and Karnali waters to India for free. None of our institutions and NGOs has so far raised any serious objections to it. If the news reports on India’s rivers-linking project are correct, India now appears to be agreeing to buy water delivered from countries like Nepal for distribution across India. As far as India’s rivers-linking plan is concerned, there is ample justification that Bangladesh should be concerned. So they are now raising their voice against the plan. It could, however, be said with irony that perhaps Nepal should be even pleased because India is now prepared to pay at least some amount for water supplied to their rivers linking project despite the fact that we were prepared to provide them regulated West Seti and other river waters for free.

It is no more a secret that neither the Nepal government nor the civil society has ever seriously raised the downstream irrigation benefit issues. Unfortunately, we are mainly concerned about the political side of water resources development, virtually shutting our eyes to economic benefits. Developed countries these days are not hesitating to go to the extent of compromising their sovereignty to a certain degree to gain strong economic foothold.

Dr Thapa was formerly with Water Energy Commission