UniSA STEM, University of South Australia, Mawson Lakes Boulevard, Mawson Lakes, South Australia 5095, Australia.
UniSA STEM, University of South Australia, Mawson Lakes Boulevard, Mawson Lakes, South Australia 5095, Australia.
Water Res. 2022 May 15;215:118273. doi: 10.1016/j.watres.2022.118273. Epub 2022 Mar 10.
Distributed infiltration systems can benefit downstream water bodies by reducing the runoff flowrate and volume discharges from the catchment. Investigating their runoff flowrate and volume reduction potential at the catchment scale will inform decision makers regarding their efficacy for managing catchment outflows. To this end, we conducted field investigations at the residential catchment scale for three years. The study monitored the catchment for one year before the installation of leaky well systems (preinstallation) and two years after installation (postinstallation). The hydrological model, calibrated to preinstallation catchment outflows, acted as a virtual control tool. Runoff flow outputs from the control model and two years of monitored runoff flow data from the postinstallation period were analysed using statistical methods. The statistical tests showed a significant 13% reduction in average flowrates in storms with a corresponding runoff flowrate of up to 50 L/s. The study further reported the ability of infiltration systems to reduce runoff volume in the catchment by 9%. This reduction was not significant, however, as per the results of the statistical analysis. We then fitted the generalized linear model (GLM) to the monitored and simulated runoff volume data. This enabled us to break down the effect of curbside infiltration systems on runoff volume according to corresponding peak flowrates during the storm. The results of the two-way ANOVA performed to detect significant differences in the regression slopes of the GLM indicated that curbside infiltration systems significantly reduced runoff volume for storms when the runoff flowrates remained below 100 L/s.
分布式渗透系统可以通过减少集水区的径流量和体积排放，使下游水体受益。研究其在集水区尺度上的径流量和体积减少潜力，可以为决策者提供有关其管理集水区流出物的功效的信息。为此，我们在住宅集水区进行了为期三年的实地调查。该研究在安装渗漏井系统之前（安装前）和安装后两年（安装后）对集水区进行了一年的监测。经过校准以适应安装前集水区流出量的水文模型充当虚拟控制工具。使用统计方法分析了控制模型的径流输出以及安装后两年的监测径流数据。统计检验表明，在相应的径流量达到 50 L/s 时，平均流量减少了 13%。该研究还报告了渗透系统减少集水区径流体积的能力为 9%。然而，根据统计分析的结果，这种减少并不显著。然后，我们将广义线性模型（GLM）拟合到监测和模拟的径流体积数据上。这使我们能够根据风暴期间相应的峰值流量，分解路边渗透系统对径流体积的影响。执行双向方差分析以检测 GLM 回归斜率的显著差异的结果表明，当径流量保持在 100 L/s 以下时，路边渗透系统可显著减少径流量。
