Let’s imagine a ship that, instead of descending through locks, rises up a mountain inside a chamber of water. That is exactly what happens in Goupitan, a dam in southwest China where the difference in level between the reservoir and the river reaches almost two hundred meters. To overcome this gap, engineers designed three consecutive elevators capable of transporting boats of five hundred tons. It is a system that combines the scale of a hydroelectric dam with the precision of a clock and has once again transformed the Wu River into a continuous navigable waterway after more than twenty years of interruption.
For years, the Wu River was a natural highway for Guizhou. From its mountains, barges descended towards the Yangtze loaded with minerals, cement or fertilizers. Everything changed with the construction of large hydroelectric dams in the early 2000s: the reservoirs generated power, but completely cut off shipping. Between 2009 and 2016 there was no continuous navigable passage in Goupitán: goods had to be unloaded before the dam, loaded onto trucks, circled the mountain and re-embarked upriver. That transshipment could take one or two days and cost more than 20,000 yuan per barge, an obstacle that discouraged river transport and made the local economy more expensive.
Three elevators, the same river and a mountain in between
Goupitan is not one boat lift, but three that work in series to allow the river to become navigable again. Each one overcomes a part of the unevenness and, between them, a connection channel It combines tunnels dug into the mountain and an aqueduct suspended over the valley. According to the Guizhou Department of Transportation, the complex forms a route of just over two kilometers where standard five-hundred-ton barges can operate. The design distributes the total elevation into three sections, with a fully balanced central level and two submersible-type ends.
This system became the first in the world to apply three consecutive lifts within the same project and to achieve an unprecedented single level lift of 127 m. The investment was around three billion yuan (about 400 million euros), and the infrastructure can move almost three million tons of cargo per year.
The operation of Goupitan is based on a principle as simple as it is effective: that of balance. Each boat enters a chamber filled with water, so the total weight barely changes as the boat floats inside. This almost constant mass is compensated by counterweights and steel cables that raise and lower the drawer with a precision of centimeters. The first and third elevators are submersible type, with the box that sinks into the water to equalize levels, while the central one uses a fully balanced system, similar to a conventional elevator but on a monumental scale.
Electric motors drive the drums that wind the cables, and the entire operation is controlled by sensors that measure tension and position in real time. If they detect a deviation, the system stops immediately.
Three years after the hydroelectric dam came into service, navigation works began. For almost ten years, the place was transformed into an engineering laboratory. Navigation tunnels had to be opened under the rock, metal towers had to be erected and the steel caissons had to be assembled by hand inside the valley. In June 2021, a boat five hundred tons completed the journey of the three elevators, marking a milestone. In 2023, after the last inspections, the Ministry of Transportation declared the system operational and handed it over to the provincial authorities for commercial exploitation.
Once in service, the system operates as a synchronized chain. Complete transit through the three levels takes approximately 38 minutes, according to official data. The process is automated: sensors, cameras and a central control room manage the gates, water pressure and cable movement.
The impact was noticeable from the first day. In November 2021, a convoy of fourteen barges carrying seven thousand tons of phosphate completed the voyage of the three lifts and marked the official return of shipping on the Wu River after more than twenty years of interruption. Since then, river traffic has established itself as a real alternative to road transport, with lower costs and a much smaller environmental footprint.
For Guizhou, a landlocked province, that difference is strategic. The Wu River connects with the Yangtze and, through it, with the port of Shanghai. The reactivation of traffic makes it possible to export minerals and construction materials directly from the interior and, in turn, receive raw materials without depending on land transportation.
Maintenance tasks are constant. Each elevator undergoes daily inspections and more in-depth checks every few weeks. The technicians, for their part, have received specific training to operate the machinery. Keeping such a structure in balance requires the same precision as building it and close operational coordination with the exploitation of the reservoir.
Goupitan’s system changed the map of boat lifts. Until it came into operation, the benchmark was the Three Gorges Dam elevator, with a drop of 113 meters. In Europe, the Strépy-Thieu stands out, in Belgium, with 73 meters, and the Scottish Falkirk Wheel, a rotating structure of 35. None approaches 199 meters that covers the whole of China nor the 127 of its central section, the highest individual elevation recorded to date.
The Goupitan boat lift is nestled in one of the most rugged landscapes in southwest China. The river meanders between forest-covered mountains and villages scattered on the banks. Official photographs taken with drones show the real scale of the complex: three gigantic chambers connected by tunnels and aqueducts, with ships that appear tiny as they ascend. The contrast between industrial precision and the geography of the valley explains part of the visual impact of seeing them in motion.
Although its purpose is strictly logistical, the place has attracted the attention of curious people and visitors. From the road that borders the reservoir and the access to the damand get panoramic viewsand media coverage has popularized aerial images of the maneuvers.
Images | Guizhou Government
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