江西赣州的宋代古城位于长江中下游平原，自古以来就是水患频发之地，它的排

The Song Dynasty ancient city in Ganzhou, Jiangxi Province is located in the middle and lower reaches of the Yangtze River. It has been a flood-prone place since ancient times. Its drainage system is still in operation. It has protected the ancient city from floods from 1000[] years ago to the present day. <br>The waterproof system of the ancient city of Ganzhou is divided into three parts, from the inside to the outside: the reservoir, the water bed, and the city wall. There are 6 pools connected to each other in the city, which can collect precipitation and provide domestic water and other functions. When the rainwater collected by the pool in the city is too much, it will be discharged outside the city through the water window through the water channel. The water window design uses water pressure to achieve only drainage. Do not backflow. Establishing a buffer zone for floods can ensure that the river water level is higher than the ancient city when the flood peak arrives, and there will be no backflow. <br>In addition, the city wall adopts a bionic design. The entire wall is elliptical and streamlined like a tortoise, which can withstand the impact of floods.

The ancient city of Song Dynasty in Ganzhou, Jiangxi Province, is located in the middle and lower reaches of the Yangtze River, has been a flood-prone place since ancient times, and its drainage system is still in operation, protecting the ancient city from flooding from 1000 years ago.<br>The waterproof system of the ancient city of Zhangzhou is divided into three parts, from the inside to the outside: cisterns, water beds, and city walls. The city set up 6 pools connected to each other, can collect precipitation, provide water for life and other functions, when the city pool collected too much rainwater, will be through the canal through the water window discharge dispensed outside the city, the design of the water window using water pressure to achieve only drainage, not pour. A buffer zone for floods would ensure that the river level in the flood peak is higher than in the ancient city and that there will be no flooding.<br>In addition, the wall adopts a bionic design, the entire wall is similar to the tortoise's elliptical streamlined type, can withstand the impact of the flood.

The Song Dynasty ancient city of Ganzhou, Jiangxi Province, is located in the middle and lower reaches of the Yangtze River Plain. Since ancient times, it has been a place of frequent floods. Its drainage system is still in operation, and it has protected the ancient city from floods since 1000 years ago.<br>The waterproofing system of Ganzhou ancient city is divided into three parts: reservoir, water bed and wall from inside to outside. Six cisterns are connected to each other in the city, which can collect precipitation and provide domestic water. When the rainwater collected by the pool in the city is too much, it will be discharged out of the city through the water window through the water channel. The design of the water window uses the water pressure to realize the drainage only and no backflow. Setting up a buffer zone for the flood can ensure that the water level of the river is higher than that of the ancient city when the flood peak comes, and there will be no backflow.<br>In addition, the wall adopts bionic design, the whole wall is similar to the oval streamline turtle, can withstand the impact of floods.<br>