Research Centre of Environmental Engineering and Management, Graduate School at Shenzhen, Tsinghua University, 518055 Shenzhen, People's Republic of China.
Sci Total Environ. 2013 Feb 1;444:255-62. doi: 10.1016/j.scitotenv.2012.11.053. Epub 2012 Dec 27.
The accuracy and reliability of urban stormwater quality modelling outcomes are important for stormwater management decision making. The commonly adopted approach where only a limited number of factors are used to predict urban stormwater quality may not adequately represent the complexity of the quality response to a rainfall event or site-to-site differences to support efficient treatment design. This paper discusses an investigation into the influence of rainfall and catchment characteristics on urban stormwater quality in order to investigate the potential areas for errors in current stormwater quality modelling practices. It was found that the influence of rainfall characteristics on pollutant wash-off is step-wise based on specific thresholds. This means that a modelling approach where the wash-off process is predicted as a continuous function of rainfall intensity and duration is not appropriate. Additionally, other than conventional catchment characteristics, namely, land use and impervious surface fraction, other catchment characteristics such as impervious area layout, urban form and site specific characteristics have an important influence on both, pollutant build-up and wash-off processes. Finally, the use of solids as a surrogate to estimate other pollutant species was found to be inappropriate. Individually considering build-up and wash-off processes for each pollutant species should be the preferred option.
城市雨水水质模型结果的准确性和可靠性对于雨水管理决策至关重要。通常采用的方法是仅使用有限数量的因素来预测城市雨水水质，这种方法可能无法充分反映水质对降雨事件的复杂响应或站点之间的差异，从而无法支持有效的处理设计。本文探讨了降雨和集水区特征对城市雨水水质的影响，以调查当前雨水水质模型实践中可能存在的误差。结果发现，降雨特征对污染物冲刷的影响是基于特定阈值的逐步的。这意味着，将冲刷过程预测为降雨强度和持续时间的连续函数的建模方法是不合适的。此外，除了传统的集水区特征，即土地利用和不透水面比例外，其他集水区特征，如不透水面布局、城市形态和特定地点特征，对污染物的积累和冲刷过程都有重要影响。最后，发现使用固体作为其他污染物的替代物是不合适的。对于每个污染物单独考虑积累和冲刷过程应该是首选。
