Windblown sand embankment weir spillway located at the tail of King Kong from the heap front end, approximately 200 meters, 2.15 meters high, its role is that when a smaller amount of water Neijiang when stone check into the treasure bottle, play a role in the embankments to ensure that irrigation water . When the flood season, when more water, a large number of river Po bottle due to the block and on this deposition, when more than the height of the spillway, the excess amount of water is automatically discharge into the river outside. Li Bing was also clever use of the treasure bottle in front of three corners circulation cliff terrain and water potential, the second the use of principles of fluid mechanics turn, simple solution to a set of sand deposition on the water projects of this international problem, let fly automatic drain Neijiang sand weir sediment volume by 75%. So that extreme admiration for Chinese and foreign scholars, amazed. Windblown sand weir is one of the three major projects in Dujiangyan Water Conservancy, looks very ordinary, in fact, its functional role is very great, we can say is to ensure that the Chengdu Plain is not the key to vital flood.
