Analysis of Pollution Load in the North of Haihe Basin in Tianjin

Based on the phenomenon of water quality deterioration in the north of Haihe Basin of Tianjin, this paper investigated the status of study area and evaluated the main pollution sources from the perspective of the point source pollution and non-point source pollution. Through field survey and related statistics, the pollution load of every catchment area was calculated using statistical and coefficient estimation methods. The results showed that the COD load was 65,283 t and NH3-N load was 12,324 t in the area and the point source pollution only contributed to 14% and5%, respectively. The four major point pollution industries included metallurgical industry, petrochemical industry,light and food industry, and the garment and textile industry. The emissions of COD and ammonia nitrogen from these four industries accounted for 73% and 84% of the total point source pollution emission, respectively. Non-point source pollution in the study area was most serious and it was the main pollution source. The farmland runoff pollution was highest, in which COD, ammonia nitrogen, total nitrogen and total phosphorus accounted for 67%, 64%, 77% and 82%,respectively. This paper provides the reference for solving the existing water pollution problem and water environment management for Haihe Basin in the north of Tianjin.