Brahmaputra reservoirs to counter China moves on river water

But plans to manage fallout from Chinese diversion of water face a hurdle: submergence of towns and village

While India is trying to expedite the construction of hydropower projects in Arunachal Pradesh, it also wants to prioritize the construction of storage projects as a fallback option. Photo: Anupam Nath/AP
While India is trying to expedite the construction of hydropower projects in Arunachal Pradesh, it also wants to prioritize the construction of storage projects as a fallback option. Photo: Anupam Nath/AP

New Delhi: India is planning to build a series of massive water reservoirs in Arunachal Pradesh in order to manage the fallout from Chinese attempts to divert river waters that flow into the Brahmaputra. But the plans have run up against a potential hurdle: the possible submergence of towns and villages.

According to documents reviewed by Mint, while India is trying to expedite the construction of hydropower projects in the strategically important north-eastern state, it also wants to prioritize the construction of storage projects as a fallback option.

These projects with large water reservoirs can store water during the monsoon and use it during the off-peak season unlike run-of-the-river (RoR) projects.

RoR projects harness the seasonal flows of the river to generate electricity and supply peak load as opposed to big dams with large water reservoirs that are good for base loads.

Reservoir projects, on the other hand, involve water storage, which addresses the risks associated with seasonal changes in the natural flow and availability of river water.

“We want the projects to be storage projects as it will help us store water in the monsoon season, even if China diverts water,” said a senior Indian government official aware of the country’s strategy.

Planners are concerned because of all Indian states, Arunachal Pradesh has the highest potential for hydropower generation, estimated at 50,064 megawatts (MW)—much needed for economic development. But less than 1%, or 405MW, has been commissioned so far, even as 94 projects with a combined capacity of 41,502.5MW have been allotted by the state government.

China has been reticent about talking about its water diversion or construction plans, and has termed the projects RoR schemes. But Indian experts, not wanting to take chances, feel that building water reservoirs in Arunachal Pradesh can minimize any impact on the Brahmaputra’s morphology, environment and power projects.

However, the construction of large storage projects can lead to issues of rehabilitation—a hotly debated issue in India.

According to documents reviewed by Mint, China has
36 projects on rivers upstream of the Brahmaputra, of which 30 have already been completed.

Of the rest, two are under-construction projects at Zangmu and Phudo Dzong. The remaining four sites are at Jiexu, Zhongda, Jiacha and on the Great Bend of Brahmaputra.

A partial blockage of the Brahmaputra river created by landslides near the Great Bend has been an area of concern for New Delhi and is being monitored by Indian intelligence agencies.

“If China diverts water, one has to have a fallback project in the form of storage projects. In the lean period or during winters, this stored water can be used. This was also the recommendation of the IMEG (inter-ministerial expert group),” said Umesh Narayan Panjiar, chairman of Bihar Electricity Regulatory Commission, and a former secretary in the ministry of water resources.

IMEG was set up by a committee of secretaries on the Brahmaputra water diversion issue.

Indian experts are of the view that the diversion of water by China will affect the 2,700MW Siang Lower project being developed by JP Associates and Siang Upper or Siang Intermediate projects planned by state-owned NHPC Ltd.

Mint reported on 3 March 2010 about Jaiprakash Hydro-Power Ltd seeking to raise tariff for power generated from its project in Arunachal Pradesh in the event of a decrease in water discharge because of Chinese actions.

However, the possible storage issue has assumed paramount importance because of the potential damage the reservoirs could cause to the local habitations.

A case in point is the Siang basin, where NHPC had planned a single power project of 9,500MW having a storage capacity of 13.91 billion cubic metres (bcm). This project would have submerged two towns—Tuting and Yingkiang —with a combined population of 17,000.

After opposition from the Arunachal Pradesh government, planners prepared a new pre-feasibility report in 2009. According to the new report, the project was divided into two sections—the Siang Upper Stage I (6,000MW) and Stage II (3,750MW) with storage of around 1.032 bcm and 0.75 bcm, respectively.

However, this vastly reduces storage capacity from 13.9 bcm to 1.78 bcm.

“To increase the storage capacity, India’s ministry of water resources is of the view that a single storage project is the ideal solution, although the Arunachal Pradesh government is averse to the idea,” said a second Indian government official, who also didn’t want to be identified due to the sensitive nature of the issue.

Arunachal Pradesh chief secretary H.K. Paliwal countered: “As of now, we are of the view that these towns shouldn’t be submerged. Once the investigations are carried out, the work will start on the second option of setting up projects in two stages.”

Storage projects will also help control floods. According to India’s ministry of water resources, planned reservoirs in the Subansiri, Dibang and Siang basins are adequate for flood moderation; with capacities of 3.02 bcm, 1.76 bcm and 1.78 bcm, respectively. However, in the Lohit basin, there is an additional requirement of 1 bcm.

These storage projects will be of immense help in the dry season, with Indian planners being of the opinion that precipitation in China contributes only 7% to the flow of three tributaries of the Brahmaputra—Subansiri, Siang and Lohit—that originate in China.

According to India’s ministry of water resources, of the total catchment area of 580,000 sq. km, 50% lies in Tibet, 34% in India, and the balance in Bangladesh and Bhutan. The average annual rainfall is 400mm in Tibet, and 3,000mm on the Indian side.

Of the 2,880km of the Brahmaputra’s length, 1,625km is in Tibet, 918km in India, and 337km in Bangladesh. According to the Central Water Commission, while 60% of the water in the Brahmaputra comes from India, 40% comes from Tibet.

However, analysts have questioned the data and are sceptical about India’s plans.

Avinash Godbole, a research assistant at the Institute for Defence Studies and Analyses (Idsa), said: “It is very difficult to build storage dams in the North-East. Then there is also the issue of relocation and rehabilitation. India has, however, raised the issue of seismic safety of the dam projects planned by China and their long-term implications.”

According to the United Nations, the cross-border annual aggregate flow of the Brahmaputra river system is 165.4 bcm, which is greater than the combined trans-boundary flow of the three key rivers—the Mekong, the Salween and the Irrawady—that run from the Tibetan plateau to South-East Asia.

“This is a good strategy,” added Panjiar, who was also additional secretary in India’s power ministry.

Alongside, New Delhi is also developing the physical infrastructure along the Brahmaputra river basins, having identified roads, bridges and air connectivity that need to be built.

The Subansiri, Lohit and Siang basins are strategically important as they are close to the international border with China. Projects with a capacity of 11,368.5MW, 7,912MW and 7,247MW have been allocated in the Siang, Subansiri and Lohit basins, respectively. However, only the 2,000MW Lower Subansiri project is under construction by NHPC.

Some of the critical infrastructure projects that have been identified for development in the Siang basin are the 100km Akajan-Likabali-Bame road link; 180km Along-Tato-Mechuka-Hirong link; the Bogibeel bridge; and extension of the existing airstrip at Along for commercial aircraft.

For the Dibang basin, projects including building the Tezu-Paya-Roing road, 90km Meka-Roing-Hunli road, 140km Hunli-Anini road and bypasses on National Highway 37 that connects Dibrugarh and Tinsukia (in Assam) with Dhola in Arunachal Pradesh. In addition, bridges such as Alubari, Dhola-Sadiya, Deopani RCC and Ipplipani are to be built.

In the Lohit basin, the road links that are to be constructed include: Digaru-Tezu-Hawai, Digaru-Tezu-Tohangam, Tohangam-Hayuliang, Demwe-Brahmakund-Arrowa-Hayuliang, Hayuliang-Changwinti-Hawai and Hawai-Walong, along with extending the existing airstrip at Tezu for operation of commercial aircraft.

“While we need development in the North-East, the government is stepping up efforts as security has become a perspective in our context,” added Godbole of Idsa, whose research area comprises China’s domestic politics, minority, environment and energy.

India and China have been engaged in a dispute over the diversion of the Brahmaputra river, which originates in Tibet. Even while India is still exploring a diplomatic option, it has initiated an action plan that would give it user rights. In the second of a three-part series, Mint chronicles India’s strategy of prioritizing the construction of water large storage projects

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