By Bo Ning, Huang Zhengping & Wang Pu

金沙江，蘊(yùn)含著無窮力量，蜿蜒于橫斷山的深山峽谷。（黃正平 攝）Jinsha River, with great power, wanders its way in the deep valley of the Hengduan Mountains. (Photo by Huang Zhengping)

大體積混凝土的溫控防裂一直是工程界的難題。為了從源頭上解決大壩的溫度裂縫問題，白鶴灘水電站工程全壩采用低熱水泥混凝土，總量達(dá)803萬立方米，在國際上屬首例。圖為業(yè)主、設(shè)計(jì)、監(jiān)理、施工各方共同檢查入倉混凝土的各項(xiàng)品質(zhì)。（黃正平 攝）Temperature control and crack prevention has long been a challenge in dam construction.In order to prevent temperature cracks from its origin, a total amount of 8.03 million cubic meters of low-heat concrete was applied to the construction of the dam of Baihetan Hydropower Station, the first of its kind in the world. In this photo, representatives from the designing,construction, supervising companies and the proprietor are inspecting the quality of the concrete. (Photo by Huang Zhengping)

“The paths on Hengduan Mountains are bumpy and hazardous, the sky is red like fire and the waters are as white as silver...” This is how the Red Army soldiers portrayed the steep mountains, deep ravines and the surging river in the Hengduan Mountains during the Long March. Today, the hydropower construction in this remote land has tamed the surging waters in the mountains and transformed the deep ravines into smooth lakes.

It was a hot midsummer day with snowy clouds curling and spreading over the mountaintops in the far distance. On the riverbanks of the Jinsha River,flowing across Sichuan Province and Yunnan Province, we witnessed the busy and on-going construction scene on the site of the Baihetan Hydropower Station and the Wudongde Hydropower Station.

After decades of on-thespot investigations, scientific experimentation, careful design and 8-years of preparation, these two massive 10-GW hydropower stations built by Three Gorges Corporation have both entered large-scale construction of dams. They are regarded as milestone projects in the history of hydropower stations both at home and abroad, following the completion of the Xiluodu Hydropower Station and the Xiangjiaba Hydropower Station on the Jinsha River. The total installed capacity of the four stations is 46.46 GW, equivalent to that of two Three Gorges Projects.

Together with the Three Gorges Dam and Gezhouba Dam, the Three Gorges Group has initiated the world's first largest clean energy corridor on the Yangtze River.

The Baihetan Hydropower Station has taken on unprecedented challenges and overcome a series of the world's toughest problems, making itself the most difficult hydropower project under construction in the world. It has broken six world records, namely, the first singleunit capacity of 1 GW under construction, the largest size of underground caverns, the largest scale of cylindrical tail water surge tanks, the highest degree of seismic resilience among 300-meter-grade arch dams, the first use of low-heat concrete for the whole 300-meter-grade arch dam, and the largest scale of nonpressure spillway tunnels, hence attracting worldwide attention.

白鶴灘水電站工程攔河壩最大壩高289米。正常蓄水位825米，防洪限制水位785米。地下廠房裝有16臺機(jī)組，裝機(jī)容量1600萬千瓦，多年平均發(fā)電量624.43億千瓦時(shí)，相當(dāng)于每年可節(jié)約標(biāo)準(zhǔn)煤約1968萬噸，減少排放二氧化碳5160萬噸。圖為建設(shè)中的白鶴灘大壩。（肖佳法 攝）The largest dam of Baihetan Hydropower Station is 289 meters high. The reservoir has a normal water storage level of 825 meters,restricted water level in fiood control of 785 meters. The underground powerhouse is equipped with 16 machine sets with an installed capacity of 16 GW. Its average annual power generation will be 62.443 TWh, an amount equal to that generated by 19.86 million tons of coal. Thus 51.6 million tons of carbon dioxide emissions will be reduced per year because of this project. This is a photo of the dam under construction. (Photo by Xiao Jiafa)

建設(shè)中的白鶴灘大壩（肖佳法 攝）Baihetan Dam under construction (Photo by Xiao Jiafa)

烈日炎炎，工人們正忙著布設(shè)壩體廊道鋼筋網(wǎng)體。（李亞隆 攝）Under the scorching sun, workers are busy laying reinforcing mesh for the dam tunnel. (Photo by Li Yalong)

烏東德水電站安裝12臺單機(jī)容量85萬千瓦的水輪發(fā)電機(jī)組，總裝機(jī)容量1020萬千瓦，年發(fā)電量389.1億千瓦時(shí)。最大壩高270米。烏東德水電站工程于2015年12月開工建設(shè)，預(yù)計(jì)2020年首批機(jī)組投產(chǎn)發(fā)電，2021年全部機(jī)組投產(chǎn)發(fā)電。圖為烏東德水電站工程建設(shè)夜景。（黃正平 攝）Wudongde Hydropower Station is designed to be equipped with 12 hydroelectric turbine sets, each with a generating capacity of 850 MW, to reach a total installed capacity of 10.2 GW and an estimated annual output of 38.91 TWh. Its dam is 270 meters high.This station commenced construction in December, 2015. The first turbine generators are expected to be commissioned in August 2020, and all of the 12 generators will be put into service by December, 2021. This is a night scene of the Wudongde Hydropower Station under construction. (Photo by Huang Zhengping)

100萬千瓦水輪發(fā)電機(jī)組，單機(jī)高50多米、重達(dá)7000多噸，是目前世界上最大的水輪發(fā)電機(jī)組。圖為水輪發(fā)電機(jī)轉(zhuǎn)輪出廠。（黃正平 攝）With a height of over 50 meters and a weight of over 7,000 tons, the 1-GW hydroelectric turbine generators used in the Baihetan Project are the largest in the world at present.In this photo, workers are preparing to transport one of the turbine runners from the manufacturer, Dongfang Electric Machinery. (Photo by Huang Zhengping)

烏東德水電站的蝸殼（黃正平 攝）The spiral case of Wudongde Hydropower Station (Photo by Huang Zhengping)

機(jī)組蝸殼焊接施工（肖佳法 攝）Welding of a metal spiral case (Photo by Xiao Jiafa)

烏東德水電站的右岸地下廠房，一個(gè)個(gè)機(jī)窩已澆筑成型，正轉(zhuǎn)入機(jī)電安裝階段。（黃正平 攝）Hydroelectric turbines to be installed in the underground plant on the right bank of Wudongde Hydropower Station(Photo by Huang Zhengping)

白鶴灘水電站工程各類洞室總長度達(dá)217千米，洞室開挖量達(dá)2500萬立方米，是國內(nèi)外水電工程中規(guī)模最大的地下洞室群。這些洞室和通道就像一個(gè)巨大的“地下迷宮”。白鶴灘水電站工程泄洪建筑物由大壩壩身6個(gè)表孔、7個(gè)深孔和左岸3條無壓泄洪洞組成，無壓泄洪洞群規(guī)模居世界第一。圖為建設(shè)中的泄洪洞，洞壁光滑如鏡。（李亞隆 攝）The total length of all caverns and caves of Baihetan Project amounts to 217 kilometers, and the excavation volumes have reached 25 million cubic meters. It is the largest underground cavern system in hydropower projects both at home and abroad. These caves and passages form a huge web-like “underground world.”Its fiood-discharge system, consisting of six surface outlets and seven mid-level orifices on the arch dam, and three non-pressure spillway tunnels on the left bank, is the largest one in the world. This photo shows the mirror-like surface of a spillway tunnel. (Photo by Li Yalong)

烏東德水電站工程泄洪洞（黃正平 攝）A spillway tunnel of Wudongde Project (Photo by Huang Zhengping)

在白鶴灘和烏東德兩座水電站施工現(xiàn)場，有這樣一群特殊的工人，他們每天工作在懸梯上。（黃正平 攝）Workers at both Baihetan and Wudongde sites work on suspended ladders every day. (Photo by Huang Zhengping)

張福瓊（前），四川涼山彝族工人，以前在新疆打工，因家鄉(xiāng)附近修建白鶴灘水電站，便與老鄉(xiāng)一起來到工地。（李亞隆 攝）Zhang Fuqiong (front) of Yi nationality from Liangshan of Sichuan Province returned home from Xinjiang Uygur Autonomous Region and came to work at the construction site of Baihetan Project with her country fellows. (Photo by Li Yalong)

烏東德水電站水墊塘邊坡混凝土施工現(xiàn)場，這樣的懸梯是工人們上下班的通道。（黃正平 攝）At the construction site of Wudongde Project, workers climb to their working spots via the cliff ladder. (Photo by Huang Zhengping)

一名女工工作之余通過微信問候家人。（黃正平 攝）A female worker sending WeChat messages to her family during a break(Photo by Huang Zhengping)