一种城市水体感官质量的评价方法

An evaluation method for testing the sensory quality of urban water

随着水十条的颁布实施,大量城市水体水质得到显著提升,而目前的水质分级评价方法难以反映城市水体的感官质量提升.本研究选择苏州市区23个城市水体采样点,通过定期监测获得了774套水质与感官评价数据.在此基础上,提出了一种符合城市水体特点的感官质量评价方法.通过考察城市水体感官质量与不同水质指标的相关性,筛选出了氧化还原电位、浊度、氨氮、溶解氧作为表征城市水体感官质量的特征性指标,并确定了不同指标水体分级的浓度限值,通过插值计算以及加权平均的计算方法,建立了城市水体感官愉悦度指数(WCI)评价方法.对该评价方法进行了验证,发现依据水质指标计算得到的WCI与现场人员感官评价结果相对误差小于40%的样本占总样本量的93%.研究结果表明,该方法可用于平原河网地区城市水体感官质量的评价,并为地方水体修复治理效果评价和公众休闲娱乐提供指导.

With the implementation of ten Water Pollution Control Directives, the qualities of a large number of urban water bodies have been significantly improved, but the existing national water quality evaluation criteria could not reveal this progress. In this study, 23 river sections in Suzhou city were selected and 774 sets of data including specific water quality and evaluating results were measured periodically. A method for evaluating the sensory quality of urban water is established. After investigating the correlation of sensory quality and several water quality indexes of urban water, four indexes including Oxidation-Reduction Potential, Turbidity, Ammonia Nitrogen and Dissolved Oxygen were selected as indicators to characterize the sensory quality of urban water. The specific concentration of each index for grading the water body were also settled. By interpolating and weighted averaging, a method of calculating a Water Comport Index(WCI) of the urban water was developed. The evaluation method was verified and was found that the WCI matched the results of the on-site observation well with 93% of data sets showed relative errors less than 40%. The results in this study demonstrate that the WCI method could be applied for urban water in plain area and will support to evaluate the effect of water restoration engineers and give guidance for the public.