From the 5,500 year-old Jawa Dam in Jordan to the dams powering entire cities, determining the largest dam in the world is harder than you might think.
Unlike the world’s biggest hotel for example, which is straightforward to determine based on the number of rooms, dams are built with different functions in mind and the function determines the size.
Water capacity, height, structure volume and installed capacity (the amount of power generated) are all perfectly acceptable metrics used to determine which are the biggest dams in the world. Therefore in this list of the biggest dams, we’ll give you the biggest by type as well as key information on each of the world’s largest dams.
Location: Sihhuan, China | Height: 305 metres | Installed Capacity: 3,600 MW
On the Jinping Bend of the Yalong River in Sichuan province in southwestern China is the Jinping-I dam. The highest dam in the world at 305 metres, it was completed in 2014. This is an arch dam, capable of producing 16-18 TW/h.
It is designed to supply energy for the growing urbanisation of the 39,600 square-mile catchment area as well as to improve flood protection for the locality.
Location: Bolívar, Venezuela | Height: 162 metres | Installed Capacity: 10,235 MW
The largest dam in the world by reservoir volume and the third largest by installed capacity, the Guri Dam was completed in 1969. Also known as the Simón Bolívar Hydroelectric Plant, this immense dam holds back the Caroni River and created the Guri Reservoir – the largest body of fresh water in Venezuela – with a volume of 135 billion cubic metres.
Generating the energy equivalent of around 300,000 barrels of oil a day, the dam produces almost 13,000 GW/h of power and supplies as much as 73% of Venezuela’s energy requirements.
Location: Khyber Pakhtunkhwa, Pakistan | Height: 143 metres | Length: 2,743 metres
Opened in 1976 on the Indus – Pakistan’s longest river – and with an installed capacity of 4,888 MW, the Tarbela Dam is not the world’s biggest dam, but it is the largest earth-filled, or embankment dam in the world.
It has a lifespan of around 85 years – it is slated to be replaced or overhauled in around 2060 – and was designed for irrigation, flood control and power generation.
Mildred Lake Settling Basin
Location: Alberta, Canada | Max. Height: 88m | Length: 11.3 miles | Type: Tailings
Known by its corporate name – the Syncrude Tailings Dam – the MLSB is a tailings dam. This means it uses earth or rock to create a barrage instead of reinforced concrete. The structure stores the by-products of mining operations, known as tailings, to the tune of 500,000 tons per day.
Although no complete inventory of the world’s tailings dams exists, the MLSB is believed to be one of the biggest dams in the world by structure volume at 540 million cubic metres. It is also the largest earth structure in the world. By comparison, the famous Hoover Dam on the Arizona-Nevada border has a structure volume of just 2.6 million cubic metres.
Three Gorges Dam
Location: Hubei Province, China | Height: 181 metres | Installed Capacity: 22,500 MW
Impounding the Yangtze River, the Three Gorges Dam is one of the world’s great engineering projects and the world’s single largest source of electricity.
Completed in 2003 at a staggering cost of almost $32 billion, the 2,335 metre wide dam is generally considered to be the biggest dam in the world. When it opened it replaced the Itaipu Dam on the Brazil-Paraguay border as the world’s largest power station and in 2020, the dam’s annual energy production reached almost 112,000,000 MW/h, again surpassing the Itaipu Dam’s 2016 record of over 103,000,000 MW/h.
When Three Gorges Dam was built, almost 40 trillion kilograms of water from the Yangtze built up behind it to a height of 175 metres above sea level. This build-up was so phenomenally powerful that it caused the Earth’s moment of inertia to change. In effect, it caused the Earth’s rotation to slow down by 0.06 microseconds (six one-hundredths of a millionth of a second).
Immense and Vital
Of the 800,000 or so structures around the world that call themselves dams, from the world’s biggest dam to the four-metre high sand dams in Kenya and Japan’s cedar dams built to minimise the effects of landslides and mudflows, each dam plays its part in keeping billions of people safe, powering homes and businesses and growing crops to feed entire nations. For the largest of them all, these immense structures demonstrate more than any other man-made construction the immense power that can be achieved through the development of great engineering dreams.