Program in Environmental Technology and Policy, Korea University, 2511 Sejong-ro, Sejong 30019, South Korea.
Department of Environmental Engineering, Korea University, 2511 Sejong-ro, Sejong 30019, South Korea.
J Environ Manage. 2019 Feb 1;231:1270-1276. doi: 10.1016/j.jenvman.2018.03.032. Epub 2018 Dec 4.
The Storm Water Management Model (SWMM), with its recently released low impact development (LID) module, is among several models used for the performance evaluation of LID facilities in reducing runoff and pollutants. Modeling is often difficult because of the variety of factors affecting the LID system. Among these factors, the effect of groundwater can be important in the LID modeling results due to the possibility of its interaction with LID. In this study, the performance of the SWMM-LID controls in predicting runoff from bioretention cells was evaluated for a site under groundwater influence. In addition, for considering the groundwater effect in the model, this study explores the utility of the SWMM groundwater model in predicting runoff under groundwater influence. Runoff from the considered watershed draining into the bioretention cells was well-simulated with very favorable performance statistic values (r = 0.96, NSE = 0.94, % difference = 2.76). However, comparison of simulated with observed runoff from bioretention cells produced weaker statistical values (r = 0.69, NSE = 0.65, % difference = 18.22), which is thought to be due to the presence of events affected by groundwater interference. Removal of these events and recalibration were able to improve the overall results, suggesting that the influence of groundwater should be taken into account for better LID modeling of the study site. In order to consider the groundwater influence, the SWMM groundwater model was used in tandem with LID controls to provide an additional influent source to bioretention cells. This resulted in a good fit for two events which were thought to be impacted by groundwater (events in which outflow exceeded inflow) and overall better performance (r = 0.95, NSE = 0.95, % difference = 3.49) compared to the results obtained by using only LID controls. In conclusion, the SWMM groundwater model can help deal with groundwater-impacted events. However, for better representation of the phenomenon, the LID module itself needs to be improved to account for direct interaction with groundwater.
雨水管理模型（SWMM）及其最近发布的低影响开发（LID）模块，是用于评估 LID 设施减少径流和污染物性能的几种模型之一。由于影响 LID 系统的因素种类繁多，建模通常很困难。在这些因素中，由于 LID 与地下水相互作用的可能性，地下水的影响在 LID 建模结果中可能很重要。本研究评估了在受地下水影响的场地条件下，SWMM-LID 控制对生物滞留池径流的预测性能。此外，为了在模型中考虑地下水的影响，本研究探讨了 SWMM 地下水模型在预测受地下水影响下径流的实用性。考虑流域排入生物滞留池的径流量得到了很好的模拟，表现出非常有利的统计值（r=0.96，NSE=0.94，差异百分比=2.76）。然而，与生物滞留池实际观测到的径流量相比，模拟结果的统计值较弱（r=0.69，NSE=0.65，差异百分比=18.22），这被认为是由于受地下水干扰影响的事件的存在。删除这些事件并重新校准能够提高整体结果，这表明应该考虑地下水的影响，以便更好地对研究地点的 LID 进行建模。为了考虑地下水的影响，SWMM 地下水模型与 LID 控制一起使用，为生物滞留池提供额外的进水源。这使得两个被认为受地下水影响的事件（流出量超过流入量的事件）拟合良好，并且整体性能更好（r=0.95，NSE=0.95，差异百分比=3.49），与仅使用 LID 控制的结果相比。总之，SWMM 地下水模型可以帮助处理受地下水影响的事件。然而，为了更好地表示这种现象，需要改进 LID 模块本身，以考虑与地下水的直接相互作用。
