Safety Evaluation Of Groundwater Drinking Water Sources In Beijing Tianjin Hebei Region

With the development of society,groundwater pollution in Beijing Tianjin Hebei region is serious,and there is a serious over exploitation phenomenon.The safety of groundwater drinking water source has been a key problem restricting the social and economic development and people's health in Beijing Tianjin Hebei region.In this paper,we build a suitable safety evaluation system for groundwater drinking water sources in Beijing,Tianjin and Hebei,evaluate the safety of water sources,and analyze the safety changes of water sources.The following research results are obtained:(1)Combined with the safety characteristics of groundwater drinking water sources in Beijing,Tianjin and Hebei and the construction principles of the safety system of groundwater drinking water sources,water quality,water quantity and ecology are selected as the first level indicators of safety evaluation,in which 39 second level indicators are selected for water quality safety,1 second level indicator is selected for water quantity,and 2 second level indicators are selected for ecology Safety evaluation system based on quantity evaluation and supplemented by ecological evaluation.(2)Compare the water quality safety of water source in 2000 and 2018,and analyze the water quality changes and reasons;The study found that the overall water quality of Beijing Tianjin Hebei region in 2018 was better than that in 2000,in which the water quality of Beijing water source became worse,unsafe water source increased by 7.15%,and there were three new water quality indicators exceeding the standard,namely total hardness,ammonia nitrogen and nitrate;the water quality of Tianjin water source also became worse,unsafe water source increased by 50%,and the number of water quality exceeding the standard did not increase.However,the water quality of water source areas in Hebei Province has improved,the safe water source areas have increased by 11.9%,and the number of water quality indicators exceeding the standard has decreased by 6,but there are four new indicators of iodide,p H,manganese and cyanide exceeding the standard.By analyzing the land use changes in the water source protection area in 2000 and 2018,the cultivated land around the water source area in Hebei Province decreased,the forest land increased,the agricultural pollution sources decreased,the water conservation capacity of the water source area increased,and the water quality of the water source area improved.However,the forest land in Beijing and Tianjin decreased,the construction land increased more,the water conservation capacity of the water source area decreased,and the pollution sources increased.(3)According to the established groundwater drinking water source safety evaluation system,the water source safety evaluation in 2000 and 2018 were compared and analyzed;It is found that 25.86% of the groundwater drinking water sources in Beijing Tianjin Hebei region are in poor safety condition,74.14% are in good safety condition,and the number of safe water sources increases from 27 to 47;Among them,the safety of water sources in Qinhuangdao,Xingtai,Chengde,Cangzhou and Tangshan has improved,and many water sources have changed from unsafe to safe;the water sources in Beijing,Tianjin and Handan have become worse.According to the changes of water source safety,the following suggestions are put forward: strengthen the water quality monitoring of water source;improve the division and management mechanism of water source protection area;improve the water supply capacity and strengthen the ecological environment management around the water source.