Feisha Dam

In the Dujiangyan Scenic Area, cross the bridge on the west side of the Dui Park and cross the Neijiang River to the right is Feisha Temple. This is also one of the three major water conservancy projects in Dujiangyan. Looking east at Feisha Temple, the opposite bank of the Neijiang River is Baopingkou and Lidui. Feisha Temple is also known as "flood discharge road" and "water reduction river". This slightly tilted dike is repaired on the side of the off-duile and at the end of the King Kong dike, and a 200-meter-wide mouth is opened from south to north according to a certain height (the river bed to the river surface 2.15 meters high), which has remarkable functions of flood discharge, sand discharge and water adjustment. As one of the three major pieces of Dujiangyan, the ancient temporary project was made of bamboo cages and pebbles, and even now it has been converted to a once-for-all concrete casting form, its appearance still looks very ordinary. In fact, this flying sand squall is very powerful, can be said to ensure that the Chengdu Plain is not flooded the key. When the water volume of the inner river is small, it stops water into the inner river irrigation area; when the water volume of the inner river exceeds the upper limit of the flow rate of the bottle, the excess water will overflow from the flying sand squall and discharge to the outer river; In the event of extraordinary floods, it will also break the embankment by itself, so that a large number of rivers will return to the current of the Lijiang River. The Lijiang River has sped from the mountains, carrying a large amount of sand and stones. If they are allowed to go down the inner river, they will silt the bottle mouth and irrigation area. Because the location design is very clever, the sand has a strong sand discharge ability, can enter the Neijiang sand and then exclude, so called the sand.

Before 2000, it was a bit level to be able to divert sand with the principle of physics! It is indeed a genius, it is worthy of being the talent that the Qin King fancy, admires, and does have a level.

Flying sand is located in the lateral overflow at the end of the fish mouth water dike, anciently called "waiting the Lang", because of the good sand discharge effect. Flying sand is used to discharge the flood discharge of the Neijiang dike, which ensures the need for water in Chengdu Plain and can discharge most of the sand and stone entering the Neijiang River.

Flying sand is one of the three major water conservancy projects in Dujiangyan, its role is to discharge function, the Lijiang water to the off-dust after forming a vortex, the bottom of the sediment is rolled back, from the flying sand drifting out of the water into the outer river. This can make the sediment and excess water into the Neijiang River discharge in time to ensure the safety of the Neijiang irrigation area and Chengdu city, ensure that the bottle mouth no matter how much the water from the Lijiang River is only entering the fixed flow, Dujiangyan has a history of 2278, you see, how wise our ancients are! Great Dujiangyan, great Li Bing father and son!

Flying sand is one of the three components of Dujiangyan water conservancy project. Flying sand has cleverly used the centrifugal effect of water flow, so that the dike has the ability to clean up the sediment by itself, which is unique and magical in many water conservancy projects. When the flow of the inner river exceeds 1,000 cubic meters per second, the diversion ratio of flying sand is more than 40 ％, and the ratio of sand can reach about 75 ％. The greater the flood, the higher the diversion ratio of flying sand, the more significant the sand discharge effect. After the sand discharge, the transfer of the bottle into the bottle only accounts for about of the total amount of the Lijiang River. That is to say, the wisdom of the ancients is amazing!