Page 4

Volume 28

[Hydrographic Map and Annotations]

Ends at the station in Liye County

Feng County, Taian Subprefecture

Wang Sluice Qiu Sluice Ru Sluice

In the 18th year of the Wanli reign 1590 CE, an imperial decree ordered the construction of the Jigou Grid Dikes Ge-tiTransverse dikes built to compartmentalize floodwaters., reaching as far as the Jing border.

Shuanggou Sluice

Dong Sluice Cang Sluice Wen Sluice Xu Sluice Cheng Sluice

Beginning of the Suining border

Lü and Chen Xing and Zhu Wei Official Xuzhou Border Jiang Han

Wherever a breach occurs, the people’s fields are transformed into a lake as far as the eye can see, and the main river channel becomes choked with silt. When the floodwaters rise, boats sail through the middle of the markets, and the people are forced to seek refuge on the mountaintops. This happens because when the water enters the Grid Dikes with great force, breaches are nearly impossible to avoid. Only by treating the dikes as a controlled perimeter—allowing enough space for the rising waters to expand and spend their energy—can the brickwork be spared. By this method of defense, the river dikes can be protected from collapse, and the people’s fields can be saved from being submerged.

Ends at the Xuzhou border

Longjia Mountain Hua Mountain

Jia River — Shares the same designation as the Line Dike original: 綫堤 (Xian-ti), likely a secondary or supplementary dike line.

Near Majia Bridge, the reinforcements should be prioritized. The various flows are gathered and directed into the Jiakou River, eventually exiting at the Great River Mouth in Qinghe County. If the water follows this direct path, the danger of collapse at the treacherous mountain sections is eliminated. Regardless of the immense labor required to build stone-reinforced dikes against the mountains, the "opening and releasing" method a strategy of controlled diversion remains the most effective. If a breach occurs to the south, it will inundate Yangzhou; if it breaches to the north near Feng and Pei counties, the collapse is total. The section near Niu Mountain has been surveyed in detail and the proposed measures have been completed.