There is only a segmentation sewage layer of 1 m thick in the study area, so, the segmentation condition is poor, without fixed place to place sewage and garbage, there are light contaminated areas of 2 600 km2, moderately polluted area of 510 km2, and severe polluted area of 663 km2. According to the degree of pollution, it is proposed that set up an underground pipe drainage sewage system to protect environment.