高地下水位地区透水铺装控制径流污染的现场实验

为确定高地下水位地区使用透水铺装对地下水水质的影响,在上海市区建造了3种实验性透水铺装停车场及1个不透水铺装对照,监测实际降雨条件下3种实验设施进、出水水质,考察其对径流中污染物的去除效果并评价设施对地下水造成污染的可能性.结果表明,3种设施对TP、TSS、COD、Cr、Mn、Cu、Zn、Pb及石油类均有良好的去除效果,而对TN的去除效果较差;3种设施中均发生了明显的NO-3-N释放现象;以水泥稳定碎石为基层的缝隙透水砖铺面以及碎石基层的缝隙透水砖铺面对NH+4-N去除效果明显好于透水混凝土铺面;不同透水铺装设施出水水质除NH+4-N之外无显著差异;现场地下水质总体上劣于上海市地下水背景值,而3种透水铺装出水总体上劣于现场地下水,且多项指标属于或接近地下水V类标准.在高地下水位地区使用无防渗衬垫透水铺装存在污染地下水的风险.

Performance of Applying Scale Permeable Pavements for Control of Runoff Pollution in an Area with High Groundwater Level

The purpose of this article was to study the effect of permeable pavements on runoff pollution control and its possible influence on groundwater quality in the area with high groundwater level. Three experimental permeable parking lots and one impermeable parking lot were built in urban Shanghai in order to monitor their quality of influent and effluent water under actual precipitation conditions, in order to investigate the performance of pollutant control effects and to evaluate the possibility of the pollution of groundwater. The results showed that all the three facilities could effectively remove TP, TSS, COD, Cr, Mn, Cu, Zn, Pb and O&G, but imposed poor removal efficiency on TN. Obvious release of NO₃^--N occurred in all three pavements. The permeable interlocking concrete pavement using cement stabilized crushed stones as base course and the one using crushed stones as base course had a better removal efficiency on NH₄⁺-N than the previous concrete one. The quality of effluent water from different permeable pavements had no significant difference except NH₄⁺-N. The in-situ groundwater quality was generally worse than background values of groundwater in Shanghai. Effluent water quality of three permeable pavements was generally worse than that of the in-situ groundwater, and a number of indicators belonged to or were close to groundwater class V standard. In the area with high groundwater level, there was risk of groundwater pollution caused by permeable pavements without liners.