Due to open this summer, China’s Huajiang Canyon Grand Bridge in Guizhou is about to become the tallest bridge in the world. This record-breaking construction project has faced numerous engineering obstacles, from working at high altitude to navigating extremely difficult mountainous terrain.
But despite the challenges, the bridge has been constructed surprisingly quickly and on a modest budget when compared to other global megaprojects. But how? Read on to discover how China built a modern marvel for comparatively little money.
All dollar amounts in US dollars.
In the mountainous Guizhou Province in southwestern China, the Beipan River passes through the rugged Huajiang Grand Canyon. Extremely steep mountain slopes create a deep divide between the Liuzhi special district of Liupanshui City and Anlong County in the Qianxinan Buyei and Miao Autonomous Prefecture
Due to the region’s challenging terrain, travelling between the two areas means winding through abrupt switchbacks on mountain roads – a route that's both time-consuming and treacherous.
Authorities came up with the idea of connecting local motorways via a bridge over the canyon, which would provide much faster journey times and jumpstart economic development in the region.
However, to avoid installing bridge support towers in the scenic and environmentally sensitive canyon, designers explored options for a steel truss suspension design. To do this, the bridge would need to have a total span of just under two miles (3,200m).
This meant the new Huajiang bridge needed to be built at an extreme height. As previously mentioned, it'll be the tallest bridge in the world upon completion, measuring an astounding 2,050 feet (625m) from the river to the bridge’s roadway.
Currently, the tallest bridge on Earth is the Millau Viaduct in France at 1,125 feet (343m). So the Huajiang bridge is not just breaking but obliterating the previous world record.
The design process hasn't been without its problems. The location of the bridge means it’s subject to frequent shifts between cold and hot air in a single day, as well as intense winds and other severe weather throughout the year.
Project managers decided that a suspension bridge design would help mitigate the impacts of these various environmental and geological conditions. Engineers designed the cables to extend from two towers, both of which would need to be well over 500 feet (152m) tall.
While this may sound daunting, the province of Guizhou is already home to nearly half of the world’s 100 tallest bridges due to its predominantly mountainous landscape. In fact, more than 30,000 bridges have been built in this region since the late 1970s, so building bridges at height has become something of a regional construction speciality.
The Guizhou Transportation Investment Group was charged with delivering the project, and construction began on 18 January 2022.
Opting for a suspension bridge design means the project has used copious amounts of steel for its girders and cables – around 22,000 tonnes no less, approximately the same weight as two Eiffel Towers.
Building at such a scale and in a remote location required trucking in copious amounts of materials, such as concrete, which was needed in large quantities for the towers and road decks.
With a steeper slope on the north side of the canyon, the two main towers vary in height. The northern tower measures 860 feet (262m) while the southern tower measures 672 feet (205m). It's reported these have been built with concrete featuring a higher-than-average proportion of cement to increase their bearing capacity.
By 24 October 2023, crews were celebrating capping off the bridge’s final tower (pictured). One of the towers will feature a glass lift leading to a bar and café, while the bridge will also boast the world's highest bungee jump, making the project a draw for tourists as well as everyday travellers.
The project schedule was set for 42 months, and the bridge has taken shape at a rapid pace. On 9 April 2024, workers began setting the main suspension cables, and they completed the installation in early September of the same year.
Crews installed the bridge’s 93 steel truss girders using specialised equipment, including the world's largest spanning cable crane. Each girder weighs more than two tonnes.
No information has been released about the size of the workforce required to build this massive infrastructure. However, the Chinese-owned contractor, Guizhou Road & Bridge Group Co. Ltd., has reported that 45 of its engineers are working on the project. Many of these engineers are recent civil engineering graduates who were born after 1990.
In addition to mitigating the Huajiang Grand Canyon Bridge’s many construction challenges, this feat of engineering will deliver incredible time savings for local residents. When the roadway fully opens on 30 June, journeys that once took two or more hours will be completed in mere minutes, and many of these will be for accessing schools, medical care and jobs.
Amazingly, this staggering feat of engineering has been realised without spending billions of dollars. The total cost for the world’s tallest bridge, with its life-changing reduction in travel time, is reported to be 2 billion yuan – the equivalent of just $280 million (£210m).
To put that price in perspective, San Francisco’s Golden Gate Bridge cost $35 million to build in 1937, which is $777 million (£585m) in today's money. That means the Huajiang Grand Canyon Bridge cost almost three times less than its American counterpart, despite being nine times higher.
In comparison to a more recent project, the world’s longest bridge – and currently the second tallest – is the 1915 Çanakkale Bridge in Turkey that spans the Dardanelles and opened in 2022 at a cost of €2.5 billion ($2.9bn/£2.2bn).
Along with the relatively lower cost, the Huajiang Canyon Grand Bridge's construction has been exceptionally fast, with the project set to be completed within just three years. By contrast, the Gordie Howe International Bridge connecting Windsor in Ontario, Canada with Detroit in the US started in 2018. It's behind schedule and over budget, and won't open until later this year at a cost of nearly $5 billion (£3.8bn).
So, how has China managed to complete this feat of engineering so quickly and cheaply? One probable factor is the project's reliance on engineers who are at the start of their careers, which presumably means they command lower salaries. The average salary in China is already comparatively low from a global perspective, at around $921 (£693) a month.
What's more, the Guizhou Road & Bridge Group Co. Ltd. is wholly state-owned. This could help it sidestep the regulatory and logistical problems private companies can often experience when taking on projects of such immense scale.
Now discover more mindblowing megaprojects around the world bankrolled by China