The Three Gorges Dam, the world’s largest hydropower project, has reached its shipping capacity and already exceeds the target set for 2030, the Ministry of Transport said. One of the key benefits of the vast infrastructure project was an increase in shipping capacity, but now engineers are struggling with the challenge of how to provide more room for cargo on the Yangtze river. The dam has made the river deeper and slower, allowing for easier navigation – especially upstream – for cargo and passenger vessels. The limiting factor for cargo, however, is the capacity of a five-step lock and a soon-to-be-completed ship lift to transport vessels across the 181-meter high dam. “We estimate the throughput of the five-tier ship lock of the Three Gorges Dam will hit 110 million tons this year, far beyond our expectations,” Li Yang, Deputy Director of the Policy Research Department of the Ministry of Transport, said at a press conference in Beijing. “The shipping capacity of the three Gorges Dam’s lock is already full.” Li said the project was designed in the 1980s when experts estimated that less than 100 million tons of shipping would pass through each year before 2030. The tonnage of shipping using the five-tier lock exceeded 100 million for the first time in 2011, more than five times the level before the dam was constructed. It reached a record high of 100.06 million tons last year, representing 40,848 cargo vessels and 2,461 passenger ships, or 300,000 tons per day. In normal conditions, ships need to wait an average of 40 hours to get through the locks. Li said a new ship lift would be completed by July next year. “But the lift’s annual throughput capacity of cargo will be just 6 million tons,” he added. The Yangtze river is the leading means to transport cargo in the mountainous Three Gorges area, the China Daily reports.