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Wanning Bridge: Exemplar of Ancient Water Conservancy

Source: Science and Technology Daily | 2024-08-28 10:47:19 | Author: ZONG Shihan

The Wanning Bridge, the oldest bridge along Beijing's Central Axis, is the only surviving Yuan Dynasty (1271-1368) bridge in the capital that is still used for transportation. It stands as a testament to ancient water conservancy technology, with its unique design embodying the achievements of ancient craftsmen in flood prevention and navigation.

Constructed in 1285, the Wanning Bridge was originally a wooden structure before being transformed into a single-arch stone bridge. It boasts dual functionality: it is both a bridge and regulates water flow as a sluice.

As a vital water conservancy hub during the Yuan Dynasty, the Wanning Bridge witnessed the transformation and utilization of the Grand Canal, the world's longest man-made canal. Under the meticulous planning of ancient hydraulic experts like Guo Shoujing, the Grand Canal was seamlessly connected to Tongzhou in Beijing and southern China. The Chengqing Upper Watergate beneath the Wanning Bridge was the final sluice for boats entering the Jishuitan Dock, the canal's northern terminus. It was the first bridge the boats crossed when departing from the dock.

Besides the Chengqing Upper Watergate, the bridge has two other watergates. The middle watergate closed and the lower watergate opened as boats approached, so that the water level would rise and propel the boats upstream. Then the middle watergate would shut, and the upper watergate open, enabling the boats to ascend to the Jishuitan Dock like climbing stairs.

The bridge is flanked by exquisitely carved beast-shaped structures — water control beasts — on its eastern and western sides. These mythical creatures embody ancient people's aspirations to prevent floods and their prayers for good fortune.

With the change of dynasties, the Wanning Bridge gradually lost its function as a passage for ships. It underwent repair and renovation during the Ming and Qing dynasties, followed by renovation to the bridge deck to meet modern transportation needs.

After restoration, this stone sentinel of the city continues to play a pivotal role in the bustling transportation system.

Editor:ZONG Shihan

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