Wella-Hewage Chathurika Subhashini, Alankarage Hewa Guna, Pezzaniti David
School of Natural and Built Environments, University of South Australia, Mawson Lakes, SA 5095, Australia E-mail:
Centre for Water Management and Reuse (CWMR), University of South Australia, Mawson Lakes, SA 5095, Australia.
Water Sci Technol. 2016;73(1):78-87. doi: 10.2166/wst.2015.464.
Increased stormwater runoff and pollutant loads due to catchment urbanisation bring inevitable impacts on the physical and ecological conditions of environmentally sensitive urban streams. Water sensitive urban design (WSUD) has been recognised as a possible means to minimise these negative impacts. This paper reports on a study that investigated the ability of infiltration-based WSUD systems to replicate the predevelopment channel-forming flow (CFF) regime in urban catchments. Catchment models were developed for the 'pre-urban', 'urban' and 'managed' conditions of a case study catchment and the hydrological effect on CFF regime was investigated using a number of flow indices. The results clearly show that changes to flow regime are apparent under urban catchment conditions and are even more severe under highly urbanised conditions. The use of WSUD systems was found to result in the replication of predevelopment flow regimes, particularly at low levels of urbanisation. Under highly urbanised conditions (of managed catchments) overcontrol of the CFF indices was observed as indicated by flow statistics below their pre-urban values. The overall results suggest that WSUD systems are highly effective in replicating the predevelopment CFF regime in urban streams and could be used as a means to protect environmentally sensitive urban streams.
集水区城市化导致雨水径流增加和污染物负荷上升，这给环境敏感的城市溪流的物理和生态状况带来了不可避免的影响。水敏感城市设计（WSUD）已被视为一种可能的手段，以尽量减少这些负面影响。本文报告了一项研究，该研究调查了基于渗透的WSUD系统在城市集水区中重现开发前河道形成水流（CFF）状态的能力。针对一个案例研究集水区的“城市化前”“城市化”和“管理后”状况开发了集水区模型，并使用多个流量指标研究了对CFF状态的水文影响。结果清楚地表明，在城市集水区条件下，水流状态的变化很明显，在高度城市化条件下甚至更严重。研究发现，使用WSUD系统可重现开发前的水流状态，尤其是在城市化程度较低的情况下。在高度城市化条件下（管理后的集水区），如流量统计数据低于城市化前的值所示，观察到对CFF指标的过度控制。总体结果表明，WSUD系统在重现城市溪流开发前的CFF状态方面非常有效，可作为保护环境敏感的城市溪流的一种手段。
