饮用水源水质预警监控断面设置方法及其应用

Method and Application of Monitoring Sections Planning for Water Quality Early Warning for Drinking Water Sources

为进一步保障饮用水源水质安全,以北江的广东辖区段(下称北江)为案例区,研究构建了饮用水源水质预警监控断面设置方法,并开展应用研究.研究结果:1系统提出了饮用水源水质预警监控断面设置思路.从断面类型上,划分为入境断面、控制断面、预警断面、目标断面4类;从断面功能上,分别定位为入境水质监控、源头影响控制、早期水质预警、目标水质保障;从断面的风险覆盖范围上,分别在面尺度、线尺度、点尺度3个层面保障水源水质安全;从而构建分类多级的饮用水源水质预警监控站网.2提出了饮用水源水质预警监控各类断面的设置方法.如入境断面的设置执行"属地管理"原则,与跨省(市)界断面保持一致;控制断面的设置遵循"快速响应"原则,在高风险源及河段下游就近布设;预警断面的设置遵循"应急缓冲"原则,断面与取水口距离的核算公式是预留的水团迁移时间、设定水文条件下水流流速2类参数的函数,预留迁移时间需要满足不小于当地区域应急响应时间的约束条件;目标断面则直接位于取水口.3北江流域饮用水源水质预警监控断面初设136个,优化核定后共计111个,包括入境断面6个、控制断面71个、预警断面26个、目标断面16个,其中有8个断面具有多重监控功能属性.4经验证,该研究中所述方法具有可操作性.

In order to ensure the safety of drinking water sources, monitoring sections planning for water quality early warning was studied, and its application was carried out by taking the Beijiang River Basin as the study area. The results showed that： 1） the general idea of monitoring section planning for water quality early warning for drinking water sources was systematically presented. As to the section types, they were divided into entry section, control section, warning section and target section. Correspondingly, from the function of the sections, they were oriented to entry water quality monitoring, pollution source effect controlling, water quality early warning and water quality target ensuring. From the risk prevention scope of the sections, the water quality safety of drinking water sources was guaranteed in three aspects, namely the polygon scale, the linear scale and the point scale. Thus, the classified and multi-level monitoring station network for water quality early warning of drinking water sources was constructed. 2） The monitoring, sections planningfor water quality early warning for drinking water sources was put forward. The planned location of entry section followed the principle of ＂ territorial management ＂, which was basically consistent with the provincial （city） administrative boundary. The setting of control section followed the principle of ＂ quick response＂, which could be planned in the nearest downstream of the high risk sources or areas. The warning section setting followed the principle of ＂ emergency buffer＂. The calculationformula for the distance between warning section and drinking water intake depended on two parameters, namely reserved water migration time and the water velocity under a certain hydrological condition. The constraint for the reserved time was no less than the emergency response time in the local area. The target section was directly located at the water intake area. 3 ） The case study showed that 136 monitoring sections for water quality early warning for drinking water sources in the Beijiang River basin were initially set. 111 monitoring sections were finalized after optimization covering 6 entry sections, 71 control sections, 26 warning sections and 16 target sections, in which 8 sections had multiple monitoring functions. 4） The case study of the Beijiang River basin proved the operability of the proposed method.