Pinglu Canal Debuts World-First Stacked Water-Saving Locks

World-First Water-Saving Locks Power China's First River-to-Sea Canal

Guangxi, China - The Pinglu Canal, the first waterway built since 1949 to link a major Chinese river system directly to the sea, has moved into its final commissioning phase with a design feature no other canal on earth has attempted: three stacked water-saving basins that lift ships across a 65-meter elevation gap while recycling most of the water they use.

Chinese state broadcaster CGTN showcased the mechanism on August 12 as the canal's operators pressed ahead with live-ship navigation trials, the last test before the 134.2-kilometer waterway opens to traffic during the China-ASEAN Expo in Nanning this September. The project, a flagship of the New International Land-Sea Trade Corridor, has drawn comparisons to the Suez and Panama canals because it connects an inland river network to the open sea.

Tags: Pinglu Canal, Guangxi, water-saving ship lock, New International Land-Sea Trade Corridor, Beibu Gulf, Qinzhou port, China-ASEAN Expo, inland waterway

How Stacked Basins Beat a 65-Meter Elevation Gap

Conventional ship locks discharge large volumes of water every time a vessel is raised or lowered, which becomes a serious constraint on a canal crossing a 65-meter difference between inland water levels and the sea. The Pinglu Canal's answer is a tiered system of water-saving pools arranged in a stacked, stepped layout at its three navigation hubs: Madao, Qishi and Qingnian, running from upstream to downstream.

Each hub operates twin single-step locks built for 5,000-ton vessels. The Madao hub, the largest of the three, houses the world's biggest inland water-saving lock: chambers 300 meters long, 34 meters wide and 8 meters deep, with a maximum operating head of 29.6 meters. Water drained from a descending chamber is captured in three levels of side basins instead of being flushed downstream, then reused to fill the opposite chamber when a ship needs to rise.

CGTN reports the design cuts water consumption by more than 60 percent compared with conventional locks, and engineers say the Madao complex alone can recycle up to 63 percent of its water by partially discharging into local reservoirs. The three hubs act as giant water elevators, moving vessels step by step between the interior and the Beibu Gulf.

A 560-Kilometer Shortcut Reshapes Southwest China's Trade

The engineering matters because of what sits at the end of the canal. Cargo from southwestern China currently travels by road or rail to ports such as Guangzhou before heading overseas, a detour that adds hundreds of kilometers and significant cost. The Pinglu Canal shortens the inland shipping distance to the sea by more than 560 kilometers for export-bound goods from the region.

Local authorities estimate the shortcut will save about 5.2 billion yuan (roughly $768 million) in annual logistics costs. Guangxi is the only Chinese region that connects to the ASEAN market by both land and sea, and the canal is expected to make that position commercially decisive: factories in Guangxi, Guizhou, Yunnan and Sichuan can now send bulk cargo downriver to Qinzhou port on the Beibu Gulf instead of routing it through the crowded Pearl River Delta.

Customs data cited by China Daily shows China-ASEAN trade reached 2.75 trillion yuan in the January-April period, up 15.7 percent year on year and accounting for 16.9 percent of China's total foreign trade. ASEAN has been China's largest trading partner for six consecutive years, and China has held the top spot for ASEAN for 17 straight years.

The Numbers Behind the 134-Kilometer Megaproject

The Pinglu Canal stretches from the Xijin Reservoir in Hengzhou through Qinzhou to the Beibu Gulf, built to Class I inland waterway standards and designed for vessels of up to 5,000 tons. Total investment is around 72.7 billion yuan, with completion originally scheduled for 2026. Beyond navigation, the project integrates water supply, irrigation, flood control and ecological improvement functions.

Construction has moved fast. The Qingnian hub was filled with water in early May, and the Madao and Qishi hubs followed in early June, achieving full-channel connectivity across all three navigation complexes. With more than 96 percent of the project complete as of that milestone, the canal entered comprehensive water-fed commissioning before transitioning to live-ship trials in August.

Project officials describe the canal as China's first full-life-cycle smart waterway, with technical standards developed by five academicians that exceed national norms. The scale has drawn international attention from infrastructure analysts, who note that few inland waterway projects of this ambition have been attempted anywhere in the world in recent decades.

What the Canal Means for ASEAN and Japan's Supply Chains

For Japan, the Pinglu Canal is more than a Chinese infrastructure story. Japanese manufacturers with plants in southwestern China, including automotive and electronics supply chains that feed ASEAN assembly lines, stand to gain from faster, cheaper access to Beibu Gulf ports. The canal also gives ASEAN exporters a new, direct route into China's interior, bypassing the traditional gateway hubs on the eastern coast.

Analysts cited by Chinese media note the waterway inherits the logic of ancient Chinese canals while borrowing from the development concepts of the Suez and Panama canals, which connected maritime shipping lanes and expanded cross-border trade. The corridor it anchors, the New International Land-Sea Trade Corridor, is designed to pull China's western regions into global trade networks - a shift with implications for how regional supply chains are organized across the Asia-Pacific.

The timing also matters: with sea lanes through the Malacca Strait under heightened strategic scrutiny, alternative trade arteries that tie China's interior to the Indian Ocean and Southeast Asia are being watched closely by logistics planners in Tokyo, Seoul and Singapore.

Full-Channel Commissioning and the September Opening

The water-filling milestones of May and June allowed the canal to achieve full-channel connectivity and launch comprehensive water-fed commissioning, according to the Pinglu Canal Group. The August live-ship navigation trials are the final test before the official opening, which is scheduled to coincide with the China-ASEAN Expo in Nanning, the Guangxi capital, in September.

Shipping companies are already positioning for the route. The trial runs have tested lock operations, channel depth and vessel handling under real traffic conditions, with the three hubs coordinating the passage of 5,000-ton vessels through the 65-meter lift. Officials say the opening will mark the first time since the founding of the People's Republic that Chinese cargo can travel from an inland river system to the open sea without transshipment.

For Guangxi, the canal is the centerpiece of a regional strategy to become a strategic gateway for domestic and international economic flows, supporting the autonomous region's "one zone, two hubs, one base and one corridor" initiative.

What to Watch For

The September opening will be the first real test of whether the stacked-basin design performs at commercial scale, and whether the canal can deliver the traffic volumes needed to justify its 72.7 billion yuan price tag. Watch for the first scheduled container services on the route, freight-rate comparisons against the Guangzhou corridor, and whether Beibu Gulf port operators expand capacity to absorb the new cargo flows.

For Japan and the wider Asia-Pacific, the more consequential question is how the canal reshapes competition for ASEAN-bound trade. If the Pinglu Canal delivers on its promise of cheaper, faster access to China's interior, it could pull a measurable share of regional logistics away from established gateways - and give infrastructure planners in other countries a new benchmark for what a modern waterway can achieve. The stacked basins at Madao, Qishi and Qingnian will be watched as proof of concept long after the opening ceremony is over.

By Kenji Tanaka, Staff Writer

This article was produced with AI-assisted research and editorial support. Sources: CGTN, China Daily, Global Times, Xinhua.