Is the South-to-North Water Diversion Pipeline Diversion or Channel Water Diversion?

The middle line main canal is 1,277 kilometers long, with a water level of 147.38 meters at the head of the canal and a water level of Tuancheng Lake at the end of the canal of 49.5 meters. The water transmission line is so long and the scale of water diversion is so large, but the drop is less than 100 meters. , which shows how difficult it is for water from the Yangtze River to reach Beijing.

The characteristic of the middle line of the South-to-North Water Diversion Project is that the entire process adopts the "artesian" method, that is, the water automatically flows northward. In order to reduce head loss and leakage along the channel, the entire channel is lined with concrete, shotcrete and other methods according to different soil types. The longitudinal slope of the main canal is 1/25000 south of the Yellow River and 1/30000 to 1/15000 north of the Yellow River.

In order to meet the requirements of the longitudinal slope of the channel and realize the natural flow of water from the south to the north, places with high terrain must be leveled off, which is called opening roads across mountains. The Fangcheng Pass in Henan is an important choke point for transporting water from the south to the north. As early as the Northern Song Dynasty, Song Taizong wanted to dig a channel from the Fangcheng Pass to divert water northward. It is said that 100,000 people were recruited to dig more than 100 miles. In the end, it failed because the soil was hard and the rocks were hard. Thousands of years later, this problem was finally overcome.

When you encounter low-lying areas, you need to build bridges over water. Aqueducts are the so-called "bridges". Aqueducts, also called water bridges, are overhead water tanks that transport channel water across obstacles such as rivers, ravines, depressions, and roads.