China breaks ground on $170 billion dam near Arunachal—why India is concerned, and what it plans to do

Indian Express

2 days ago

China's official announcement of the start of construction on a massive hydropower project on the Yarlung Zangbo – just before the river bends into Arunachal Pradesh as the Brahmaputra – marks a pivotal moment for both India's strategic interests and China's economic goals.
With a planned investment of nearly $170 billion, it is set to be China's largest infrastructure project since the Three Gorges Dam, and a major stimulus for the domestic economy.
But across the border in Arunachal Pradesh, the project has raised alarm over potential downstream impacts, with fears of the Siang region being vulnerable to a 'water bomb'. India, in response, has proposed a large storage project to counter the Chinese dam – but progress has been slow.
The Chinese Premier Li Qiang on July 19 announced the launch of construction and the formation of a new entity – China Yajiang Group Co Ltd – to build and operate the hydropower project, according to state-run Xinhua.
The project will comprise five cascade hydropower stations spread across a 50-kilometre stretch of the river that drops 2,000 metres, offering vast hydropower potential. With a planned capacity of 60 GW, it will be roughly three times the size of the Three Gorges Dam. While cascade projects typically include storage to regulate flow between stations, the extent of planned storage has not been revealed.
Chinese markets responded positively to the announcement on Monday, with shares of major construction and equipment firms surging. Experts see the project as a major stimulus for the domestic economy.
While the storage capacity of the Chinese project is not known – a key factor in assessing China's ability to regulate water flow into India – concerns are mounting in Arunachal Pradesh. Earlier this month, Chief Minister Pema Khandu warned that the dam is the biggest issue facing India, second only to the 'military threat', and could be used as a 'water bomb'.
'Suppose the dam is built and they suddenly release water, our entire Siang belt would be destroyed. In particular, the Adi tribe and similar groups… would see all their property, land, and especially human life, suffer devastating effects,' Khandu told PTI on July 9.
While around 30 per cent of the Brahmaputra's waters originate in China, the majority comes from rainfall within India's catchment areas. As a result, the Chinese dam's immediate impact is expected to be felt most in Arunachal Pradesh – particularly in the Siang region.
In addition to flooding concerns, the Chinese dam could also disrupt water flow to proposed downstream hydro projects. The Northeast holds nearly half of India's 133 GW hydropower potential, over 80 per cent of which remains untapped. Of the 60 GW estimated potential, about 50 GW lies in Arunachal Pradesh alone.
To counter China's upstream development, India has proposed the 11.2 GW Upper Siang Multipurpose Project – a massive storage-based dam in the Siang district. The project is expected to act as a strategic buffer to regulate water flow and protect downstream populations and infrastructure.
However, progress has been slow, The Indian Express had earlier reported. Three years after the Ministry of Jal Shakti tasked NHPC Ltd with preparing a pre-feasibility report, vital investigations remain stalled due to local opposition.
In response to a question on delays at an Idea Exchange earlier this month, Union Jal Shakti Minister CR Patil said, 'China can do whatever it wants, we are fully prepared. PM Modi is quite serious about it. Work will start.'
An NHPC official told The Indian Express in June that the project can act as 'a regulating scheme to mitigate adverse impact of both acts of water diversion and artificial floods by the upstream Chinese development'. Once complete, the Upper Siang project would be India's largest hydropower station.