岛屿硬化集水面雨水弃流方案与分质收集策略研究

通过研究海南岛文昌市水泥屋顶和水泥路面上的雨水径流特征，建立了岛屿地区不同硬化集水面的雨水弃流方案和分质收集策略.在降雨初期，水泥路面和水泥屋顶均发生明显的冲刷效应，水泥路面雨水径流污染物浓度远高于水泥屋顶，且不同硬化集水面上前30%雨水中的污染物浓度均高于后70%的雨水.通过与相关水质指标对比得出，水泥屋顶雨水径流可作为饮用水水源，水泥路面雨水径流经处理可作为城市杂用水使用.通过建立雨水径流污染物累积-冲刷经验模型，可计算不同硬化集水面的弃流雨量，并以此为依据制定了弃流方案.以两种典型硬质化集水面径流污染物传输特征、水质特征和弃流方案为基础，分别提出了屋顶雨水收集方案和多种生态方法协同作用的路面雨水收集方案，可为岛屿地区的雨水收集利用方案提供参考依据.

Strategies of first-flush diversion and dual rainwater harvesting from impervious catchment in island area

In this study, we investigated the characteristics of the rainwater runoff from cement roof and pavement in Wenchang city, Hainan Province to establish the strategies for diverting first-flush and collecting rainwater from different impervious catchment. It was found that first flush effect occurred in most rainfall events. The pollutant concentrations of rainwater runoff from cement pavement were much higher than those on cement roof, while the concentrations of pollutant in the initial 30% rainwater from different impervious catchments were higher than those in the latter 70%. By comparing with relevant water quality indexes, the rainwater runoff from cement roof could be used as drinking water, and rainwater from cement pavement could be harvested for urban miscellaneous water after treatment. According to the development of stormwater runoff pollutant build-up and wash-off model, volumes of diverted water on different impervious catchment could be calculated and the diversion strategy was then established. Correspondingly, the household and eco-friendly rainwater harvesting strategies were developed with respect to two impervious catchments based on the transport characteristics and quality of runoff pollutants, first-flush diversion and maximum amount of water that can be availably harvested. Hereby, it provides a valid reference basis for rainwater harvesting in island.