Step aside, Three Gorges Dam. China’s latest colossal infrastructure project, if completed, will be the world’s largest hydropower dam, high up in the Tibetan plateau on the border with India.

靠边站吧，三峡大坝。中国最新的大型基础设施项目一旦完工，将成为世界上最大的水电大坝，它位于与印度交界的青藏高原。

China says the Motuo Hydropower Station it is building in Tibet is key to its effort to meet clean energy targets. Beijing also sees infrastructure projects as a way to stimulate the sluggish Chinese economy and create jobs.

中国表示，它正在西藏建设的墨脱水电站是实现清洁能源目标的关键。中国政府还将基础设施项目视为刺激疲软的经济和创造就业机会的途径。

But this project has raised concerns among environmentalists and China’s neighbors — in part, because Beijing has said so little about it.

但这一项目引起了环保人士和邻国的担忧，部分原因是中国政府对此透露的信息太少。

The area where the dam is being built is prone to earthquakes. The Tibetan river being dammed, the Yarlung Tsangpo, flows into neighboring India as the Brahmaputra and into Bangladesh as the Jamuna, raising concerns in those countries about water security.

修建大坝的地区容易发生地震。被筑坝的藏南河流雅鲁藏布江在流入邻国印度后被称为布拉马普特拉河，流入孟加拉国后则被称为贾穆纳河，大坝引发了这些国家对水资源安全的担忧。

What’s known about the project?

关于这个项目，目前已知哪些信息？

China announced in late December that the government had approved construction of the Motuo project in the lower reaches of the Yarlung Tsangpo, but it has released few details about it. That includes the cost of the project, where the money will come from, what companies are involved and how many people are likely to be displaced.

中国于去年12月下旬宣布，政府已批准在雅鲁藏布江下游修建墨脱大坝，但它几乎没有公布任何细节。其中包括项目成本、资金来源、涉及哪些公司以及可能会被搬迁的人口数量。

What is known is that the dam will be in Medog County in Tibet, in a steep canyon where the river makes a horseshoe turn known as the Great Bend, then falls about 6,500 feet over roughly 30 miles.

已知的是，大坝将位于藏区墨脱县，建在一个陡峭的峡谷中，那里的河流形成了一个马蹄形弯道，被称为“大拐弯”，然后江水在大约48公里的距离内下降约2000米。

By harnessing the kinetic energy of that drop, the hydropower station could generate 300 billion kilowatt-hours of energy per year, the state-owned Power Construction Corporation of China, or PowerChina, estimated in 2020. That would be triple the capacity of the Three Gorges Dam, currently the world’s biggest, which cost China about $34 billion to build.

据国有企业中国电力建设集团（简称中国电建）2020年的估计，利用这一落差的动能，该水电站每年可发电3000亿千瓦时。这将是目前世界上最大的三峡大坝发电量的三倍，三峡大坝的建设花费了中国约340亿美元。

China has not disclosed which company is building the dam, but some analysts say PowerChina, the country’s largest builder of hydropower infrastructure, is most likely involved. The company did not respond to requests for comment.

中国没有透露是哪家公司在建造这座大坝，但一些分析人士称，中国最大的水电基础设施建造商中国电建很可能参与其中。该公司没有回应置评请求。

Experts say construction in the Great Bend, a 500-meter-deep canyon with no roads, would probably take a decade because of the technical challenges.

“大拐弯”是一个500米深的峡谷，没有道路，专家称，由于技术上的挑战，大坝建设可能需要十年时间。

雅鲁藏布江大拐弯。

Even the dam’s basic design is unknown.

甚至连大坝的基础设计都不得而知。

According to Fan Xiao, a senior engineer at the Sichuan Bureau of Geology who spoke to The New York Times, one proposal, which he saw as a likely approach, involved building a dam near the top of the Great Bend and diverting the water through enormous tunnels drilled into the canyon.

四川省地质局高级工程师范晓在接受《纽约时报》采访时说，他认为一种可能的方案是在“大拐弯”顶端附近修建大坝，然后通过峡谷中钻凿的巨大隧道引水。

China’s top leader, Xi Jinping, has promised that the country’s carbon emissions will peak around 2030 as it replaces coal with renewable sources of energy. The ruling Communist Party, which uses massive public works projects to showcase its engineering prowess, has for years studied ways to tap into the power of the Yarlung Tsangpo.

中国最高领导人习近平承诺，随着可再生能源取代煤炭，中国的碳排放量将在2030年左右达到峰值。执政的中国共产党利用大型公共工程项目展示其工程实力，多年来一直在研究如何利用雅鲁藏布江的力量。

Are there environmental risks?

是否存在环境风险？

The same forces that created the Great Bend pose risks to the dam China is building on it. The Tibetan plateau was formed by a collision between the Indian and Eurasian tectonic plates millions of years ago. To this day, the Indian plate is still slowly moving toward the Eurasian one, which is why the Himalayas are regularly hit by earthquakes.

塑造雅鲁藏布江大拐弯的地质力量同样对中国在此修建的大坝构成威胁。青藏高原是数百万年前印度板块和欧亚板块碰撞形成的。时至今日，印度板块仍在缓慢地向欧亚板块移动，这就是喜马拉雅地区经常发生地震的原因。

Such seismic events threaten the safety of dams. Chinese officials said cracks appeared on five hydropower dams in Tibet after a magnitude 7.1 earthquake struck near the city of Shigatse this month, killing more than 120 people.

此类地震事件威胁着大坝的安全。中国官员说，1月日喀则市附近发生7.1级地震后，西藏五座水电站大坝出现裂缝，地震造成120多人死亡。

Even if the Motuo dam is built well enough to withstand an earthquake, the landslides and mudflows resulting from quakes are difficult to contain and can kill people living nearby. Experts say the massive excavation involved in dam construction could make such disasters more likely.

即使墨脱大坝建造得足以抵御地震，地震引发的山体滑坡和泥石流也很难控制，并可能导致附近居民丧生。专家称，大坝建设过程中涉及的大规模开挖可能会使此类灾难更有可能发生。

What about the people living there?

生活在那里的人会面临什么？

It is hard to know how the project is being received by Tibetans and members of other, smaller ethnic groups who live in the area. Tibet is tightly restricted by the Communist Party, which has encouraged Han Chinese people to move to the plateau and strictly controlled the practice of Tibetan Buddhism. Tibet is open to foreigners only by permit, and it is usually off-limits to foreign journalists.

很难知道藏族人和生活在该地区的其他少数民族对该项目有何看法。西藏受到共产党的严格限制，共产党鼓励汉族人迁往西藏，并严格控制藏传佛教的活动。只有获得许可，外国人才能进入西藏，而且外国记者通常被禁止进入。

In the past, Tibetans have held protests against hydropower dam projects that threatened to displace them, including a demonstration last year in Sichuan Province, according to a news report.

据一则新闻报道称，藏族人过去曾举行过抗议活动，反对可能导致他们流离失所的大坝项目，包括2024年发生在四川的一次示威活动。

印度一个藏人市场上抗议中国水坝项目的横幅。

The Motuo dam project is expected to bring more changes to Medog, which was once China’s most remote county. The government has built highways into the region that have drawn tourists and adventure travelers in recent years, according to Matthew Akester, a Tibet researcher based in India.

墨脱大坝预计将给曾是中国最偏远县城的墨脱县带来更多变化。驻印度的西藏研究员马修·阿克斯特表示，近年来，政府在该地区修建了高速公路，吸引了游客和探险旅行者。

Now, people will have to be relocated to make way for the dam, which may require farmlands and towns to be submerged. It is unclear how many people could be affected. Medog has a population of 15,000.

现在，人们必须搬迁，为大坝让路，这可能需要淹没农田和城镇。目前还不清楚有多少人会受到影响。墨脱县有1.5万人口。

Tibet, which is vast but sparsely populated, does not need a lot of energy, and the dam’s estimated capacity would also exceed what neighboring provinces require, Mr. Fan said. Nearby Sichuan and Yunnan have many hydropower plants, producing more energy than the region needs. And sending the power over long distances to other parts of China would be expensive.

工程师范晓说，西藏幅员辽阔，但人口稀少，并不需要大量能源，而且大坝的预计发电量也将超过周边省份的需求。邻近的四川和云南有许多水电站，生产的能源超过当地需求。而且将电力远距离输送到中国其他地区的成本也很高。

How are India and Bangladesh reacting?

印度和孟加拉国对此有何反应？

The dam could affect people living downstream in the Indian states of Arunachal Pradesh and Assam, as well as in Bangladesh. If the dam trapped sediment, that would make the soil along the river downstream less fertile and erode riverbanks and coastlines in India, said Dr. Kalyan Rudra, a professor of river science and the chairman of the West Bengal Pollution Control Board, a government body.

墨脱大坝可能会影响下游印度阿鲁纳恰尔邦和阿萨姆邦以及孟加拉国的居民。河流科学教授、政府机构西孟加拉邦污染控制委员会主席卡扬·鲁德拉博士表示，如果大坝拦截沉积物，下游沿河土壤的肥力就会降低，河岸和印度的海岸线也会受到侵蚀。

Scientists in India and Bangladesh have asked China to share details of its plans so they can better assess the project’s risks. Indian diplomats have also urged Beijing to ensure that the project will not harm downstream states. China says it has taken measures to prevent negative consequences for its neighbors.

印度和孟加拉国的科学家要求中国分享其计划的细节，以便他们能够更好地评估该项目的风险。印度外交官也敦促中国政府确保该项目不会对下游国家造成损害。中国表示已采取措施防止对邻国造成负面影响。

China’s secrecy is fueling mistrust, said Genevieve Donnellon-May, a researcher at the U.K.-based Oxford Global Society who studies water policy and environmental conflict. “Without Beijing releasing hydrological data and detailed plans for the dam, India and Bangladesh are left in the dark, so it’s harder to prepare to mitigate any potential impacts from it,” she said.

总部位于英国的牛津全球学会研究水政策和环境冲突的研究员吉纳维芙·唐尼龙·梅说，中国的保密加剧了不信任。她表示：“如果中国政府不公布大坝的水文数据和详细计划，印度和孟加拉国就会被蒙在鼓里，因此更难做好准备来减轻大坝可能造成的影响。”

Both China and India have accused each other of trying to exert control over water resources for strategic or economic gain — what some experts and officials call “hydro-hegemony.” The dam could be seen as a way of projecting Chinese power near the disputed border with India, including in Arunachal Pradesh, which China claims as its territory.

中国和印度都指责对方试图控制水资源以获取战略或经济利益——一些专家和官员称之为“水力霸权”。该大坝可被视为中国在与印度有争议的边境地区，包括中国声称是其领土的阿鲁纳恰尔邦投射力量的一种方式。

Because it is upstream, “China can make decisions that directly affect the water flow downstream, raising fears in India,” Ms. Donnellon-May said.

由于中国位于上游，“中国可以做出直接影响下游水流的决定，这引起了印度的担忧，”吉纳维芙·唐尼龙·梅说。

Some officials in India have proposed building a large dam in a tributary of the Brahmaputra to store water and counter any reduction in flow that the Tibet dam might cause. But Dr. Rudra of the West Bengal Pollution Control Board said such a dam could cause the same problems with soil fertility and erosion.

印度的一些官员建议在雅鲁藏布江的一条支流上修建一座大坝来蓄水，以应对西藏大坝可能造成的流量减少。但西孟加拉邦污染控制委员会的鲁德拉说，这样的大坝可能会造成同样的土壤肥力和侵蚀问题。