Studies On Beijing Rural Non-centralized Water Source Protection Measures

In recent years problems like the regional groundwater level drop and groundwater pollution in Beijing area have been further aggravated and become more and more apparent, even with the groundwater in some areas not attaining the hygienic standard for drinking water. Daily water supply scale of water supply sources of rural water supply, by comparison with that of the centralized water source field of city water supply, generally remains under 10,000m3,which refers to the non-centralized water source field, i.e. centralized water source. So it is essential to detect the status of non-centralized water source in rural area, study and make out feasible and operable protection measures so as to ensure that the water source quality is qualified.Based on the work of predecessors, aiming at the non-centralized groundwater sources of rural area in Beijing, plenty of relevant data are collected and analyzed, rural drinking water quality investigation and that of pollution source around water source wells are made, after that, the water resources, water quality and water protection status are correspondingly checked clearly. Then the cause of groundwater quality is analyzed by summarizing groundwater characteristics and its evolutionary law. Computed according to the water balance method, city groundwater exploitable yield from 1980 to 2000 is 26.05×108 m3. Also, by single index method and comprehensive assessment method, the non-centralized water source quality is assessed. The result is that plain area with concentration exceeding the standard water quality takes up 33% of the total area, whereas that of the mountain area only covers 0.4% of the total area.On foundation of the comprehensive research, protection measures in terms of water quantity, water quality and water management mechanism are put forward. First in water quantity protection, what should do is to control the water exploitation, and build economic means such as water charge administration mechanism, so as to carry out water saving. Second in water quality protection, based on the original water vulnerability appraisal of plain area, add aquifer vulnerability qualitative assessment of mountain area in order to realize a city-scope groundwater vulnerability appraisal. Besides, it is suggested to take reasonable planning, controlled construction scale for different vulnerability partitions. Some prevention measures can be made such as setting up rural-scale sewage pipe collecting systems, building sewage treat projects, centrally treat the domestic sewage water and eliminate each kind of pollution sources etc. Furthermore, it brings forward that the centralized water supply source plants should be divided into the first-class conservation area and second-class conservation area separately and the rural-scale water supply station should be divided into the first-class conservation area, which can make the protection area division more scientific and reasonable. Third in the water management measures, it is suggested to make out a series of feasible and operable non-centralized water source protection methods, further improve the management mechanism and to push the intensive water supply. Also what should do is to build emergency handling mechanism for unexpected water quality emergency incidents and set up water quality monitoring system and management information system as well.