50 Fun Facts About Three Gorges Dam

The Three Gorges Dam spans which river?

It sits near Sandouping in Yichang, just downstream of the gorges that give it its name.

In which Chinese province is the Three Gorges Dam?

The reservoir behind it stretches hundreds of kilometres back towards Chongqing.

What is the Three Gorges Dam's installed generating capacity, the largest of any power station on Earth?

The next-biggest hydro plant, also in China, manages 16,000 MW.

How many main turbines does the Three Gorges power plant have?

Two smaller 50 MW units power the plant itself.

What is the output of each of the dam's main generators?

Each unit weighs about 6,000 tonnes and spins at 75 revolutions per minute.

Which Chinese revolutionary leader first envisioned a great dam on China's longest river, in a 1919 book?

He reckoned a dam of 30 million horsepower was possible downstream of the gorges.

Which agency's chief engineer, John L. Savage, drew up a dam proposal in 1944?

Some 54 Chinese engineers went to America for training, but the civil war halted the plan.

What was Mao Zedong's 1956 poem about a dam on the river called?

Two years later, after the Hundred Flowers Campaign, engineers who criticised the project were imprisoned.

Which nearby dam did Mao's government build first, before the Three Gorges, between 1970 and 1988?

Its profits later helped fund the Three Gorges, and water released from the big dam still powers it downstream.

What unusually low share of National People's Congress delegates voted for the Three Gorges Dam in 1992?

Of 2,633 delegates, 177 voted against and 664 abstained.

On what date did construction of the Three Gorges Dam officially begin?

The premier who launched it was himself a Moscow-trained hydroelectric engineer.

Which Moscow-trained Chinese premier championed and launched the Three Gorges project?

He later also began preparations for the Shenzhou crewed space programme.

In which year did the power plant become fully operational, with its last turbine online?

The dam body itself had been finished six years earlier.

Roughly how tall is the Three Gorges Dam?

Its concrete wall stands 181 m above the bedrock and the structure runs 2,335 m across the valley.

The dam used 463,000 tonnes of steel, enough to build how many Eiffel Towers?

It also swallowed 27.2 million cubic metres of concrete and moved 102.6 million cubic metres of earth.

What is the designed maximum water level of the reservoir above sea level?

That is 110 m above the river downstream; the level is drawn down to 145 m each spring before the rains.

About how long is the reservoir behind the dam at full level?

It holds 39.3 cubic kilometres of water over a surface of about 1,045 square kilometres.

The dam cost an estimated 180 billion yuan. By which date had the entire cost been recovered?

Nearly half of what was spent by 2008 went on relocating residents rather than on construction.

Estimates of how many people were displaced by the dam's reservoir range between what figures?

Some 13 cities, 140 towns and 1,350 villages were partly or wholly flooded.

Which Canadian photographer documented the dam's impact on towns such as Wanzhou between 2002 and 2005?

Israeli photographer Nadav Kander and Chengdu-based Muge also recorded the transformation.

How many stages does each of the dam's two flights of ship locks have?

Transit takes about four hours, and the chambers can hold ships of up to 10,000 tons.

What device, completed in 2016, lets vessels of up to 3,000 tons bypass the locks in well under an hour?

It climbs a toothed rack with helical gears and takes well under an hour.

What vertical distance does the dam's vessel elevator carry boats?

The German firm Lahmeyer designed it; the first cargo ship was lifted in July 2016 in about eight minutes.

Officials said the dam would boost annual shipping through the gorges tenfold, to what figure?

By 2022 the locks were handling nearly 160 million tons, well past the original goal.

The dam is meant to cut major floods from once every 10 years to once every how many?

Its flood storage capacity is 22 cubic kilometres.

The 1954 flood that killed 33,167 swamped which city of 8 million for over three months?

The Jingguang Railway was out of action for more than 100 days.

Which extinct river dolphin do some Chinese government scholars say the dam killed off directly?

It is thought to be the first dolphin species driven to extinction by humans and has not been definitively seen in over 20 years.

Which giant river fish, once over 3.6 m long, was declared extinct in 2022?

Also called the Chinese swordfish, it was one of the largest primarily freshwater fish ever known.

Which critically endangered bird, with only 3,000-4,000 left, winters in wetlands threatened by the dam?

The river basin holds 361 fish species and 27% of China's endangered freshwater fish.

In 2005 NASA scientists calculated that the water stored behind the dam would lengthen Earth's day by how much?

The shifted mass also makes the planet very slightly rounder in the middle.

Roughly how many hairline cracks were observed in the dam right after the reservoir was first filled?

An experts group still gave the project a good-quality rating; all 163,000 concrete units passed testing.

The dam was once expected to supply 10% of China's electricity. By 2024, roughly what share did it provide?

Demand grew far faster than planners projected, reaching 9,852 TWh in 2024.

In 2020, after heavy monsoon rains, the dam set a world record for annual output of nearly how much?

It beat the 103 TWh record set by the Itaipu Dam in 2016.

The dam's 2018 output of 101.6 TWh compared how with the Hoover Dam's?

Fourteen of the main generators sit on the north side, 12 on the south and six underground.

What kind of turbine does the Three Gorges plant use?

They are around 10 metres in diameter and turn at 75 rpm, so the rotors need 80 poles to make 50 Hz power.

Joint ventures pairing Chinese firms with which Western companies built the dam's generators?

A technology-transfer agreement was signed along with the contract.

Which listed subsidiary of the state's Three Gorges Corporation runs the dam's generating business?

Nine provinces and two cities take electricity from the dam, with Shanghai getting priority.

Which Jinsha River dam became the world's second-largest hydro plant in 2022?

Together the four Jinsha dams have 38,500 MW of capacity, almost double the Three Gorges.

Archaeologists recovered roughly how many artefacts from the area flooded by the reservoir?

They excavated 723 sites, and the Chongqing China Sanxia Museum was built to house the finds.

Which site with 1,200 years of carved fish and water-level inscriptions became an underwater museum in 2009?

Its fish-eye carvings marked the river's lowest levels, forming the world's longest such hydrological record; the museum opened in 2009.

Which of the Three Gorges lies furthest downstream, closest to the dam?

The three gorges together stretch 311 km from Baidicheng in Chongqing to Nanjin Pass at Yichang.

The river the dam controls ranks where among the world's rivers by length?

It runs 6,236 km from the Tibetan Plateau to the East China Sea, and its basin holds nearly a third of China's people.

Which advisory body opposed the proposed dam, convening expert panels that urged delay?

The party had revived the plan in the Reform era, aiming to start building in 1986.

What did a 2004 US Department of Defense report suggest some in Taiwan saw the dam as?

Beijing called the report a 'Cold War mentality'; a Taiwanese adviser dismissed missile talk as ridiculous.

Between which months does the dam draw down its reservoir each year, lowering the level to 145 m?

Since 2003 that has sent an extra 11 cubic kilometres of dry-season water to cities and farms downstream.

In the July 2010 South China floods, peak inflow at the dam reached what rate, beating the 1998 floods?

The reservoir rose nearly 3 m in 24 hours while outflow was held to 40,000 m³/s.

The dam locks are 280 m long, which is how much longer than the locks on the St Lawrence Seaway?

They are, however, only half as deep at 5 m.

The dam generates power at 20 kV. To what voltage is it stepped up for long-distance transmission?

Three direct-current lines carry 7,200 MW to the East China Grid, and another 3,000 MW goes south to Guangdong.

When did Three Gorges' 14.1 GW first overtake Itaipu as the world's largest hydro station?

The last of the underground generators later pushed it to 22.5 GW.

What type of dam is the Three Gorges, a design said to resist even nuclear attack?

Its sheer mass, rather than an arch, holds back the reservoir.