Using DEM for hydrological analysis, the extracted river network is inconsistent with the actual river.

It can't be solved, because dem data is only elevation data, and it can't consider the influence of river filling, water surface tension and water surface width change. In other words, the lowest point on the ground is not necessarily where rivers pass, especially in plain areas. There are many rivers on the ground.

Dem data is for hands-on use only. As an excellent giser, he must be able to combine satellite remote sensing data, ground measured data, aerial photography data and aerial survey data, and at the same time have enough basic knowledge of geography, philosophy, geology and hydrology, so as to make a general analysis of hydrological network. At present, the excellent giser in China comes from environmental science, hydrology and water resources, physical geography and astrophysics, and there are few computer systems, which is why.

So your problem can be extracted by dem, but it needs to be corrected by remote sensing interpretation. If you want to be accurate, you can buy a topographic map to correct the uncertain places, and at the same time, you can actually conduct field surveys to determine whether the water network is consistent.

Are years of experience. Please accept it and don't copy it.