Towsif Khan Sami, Sample David J, Wynn-Thompson Theresa, Butcher Jon
Department of Biological System Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA, 24061, United States.
Department of Biological System Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA, 24061, United States; Hampton Roads Agricultural Research and Extension Center, Virginia Polytechnic and State University, Virginia Beach, VA, 23455, United States.
J Environ Manage. 2025 Feb;374:123994. doi: 10.1016/j.jenvman.2024.123994. Epub 2025 Jan 12.
Due to the recent improved availability of global and regional climate change (CC) models and associated data, the projected impact of CC on urban stormwater management is well documented. However, most studies are based on simplified design storm analysis and unit-area runoff models; evaluations of the long-term, continuous hydrologic response of extensive stormwater control measures (SCM) implementation under future CC scenarios are limited. Moreover, channel stability in response to CC is seldom evaluated due to the input data required to develop a long-term, continuous sediment transport model. The study objective was to evaluate the impact of CC on storm event-based flow regimes and channel stability in a small, urbanized catchment (0.9 km) in Montgomery County, Maryland, USA. This study employed a previously developed sequential, hierarchical modeling approach, integrating a watershed-scale Storm Water Management Model (SWMM) with the Hydrologic Engineering Center River Analysis System (HEC-RAS) to achieve the study goal. Ensemble modeling results indicate that conclusions related to impacts on SCM performance drawn from simplified, unit area models are not supported by findings from dynamic, continuous simulations that consider the complexities of real urban catchments and SCM interactions. Despite a general decrease in the total rainfall amount of individual storm events for most storm events, there is a noted increase in intensity for nearly all future storm events compared to current climatic conditions. This change in storm event-based rainfall pattern is expected to drive the catchment-scale hydrology to a flashier regime in the future, which in turn is expected to increase the extent of channel erosion compared to the current climate condition. A multicriteria design approach considering the interplay of multiple SCMs and local sediment transport capacity is thus necessary to ensure channel stability under changing climate.
由于近期全球和区域气候变化（CC）模型及相关数据的可得性有所改善，CC对城市雨水管理的预计影响已有充分记录。然而，大多数研究基于简化设计暴雨分析和单位面积径流模型；在未来CC情景下对广泛雨水控制措施（SCM）实施后的长期连续水文响应的评估有限。此外，由于开发长期连续泥沙输运模型所需的输入数据，很少评估CC对河道稳定性造成的影响。本研究目标是评估CC对美国马里兰州蒙哥马利县一个小型城市化流域（0.9平方公里）基于暴雨事件的水流状况和河道稳定性的影响。本研究采用了先前开发的顺序分层建模方法，将流域尺度的雨水管理模型（SWMM）与水文工程中心河流分析系统（HEC-RAS）相结合以实现研究目标。集合建模结果表明：考虑到真实城市流域和SCM相互作用的复杂性，从简化的单位面积模型得出的有关对SCM性能影响的结论，并不被动态连续模拟的结果所支持。尽管大多数暴雨事件的单次暴雨总降雨量普遍减少，但与当前气候条件相比，几乎所有未来暴雨事件的强度都有显著增加。基于暴雨事件的降雨模式的这种变化预计将在未来使流域尺度的水文状况转向更湍急的状态，这反过来预计与当前气候条件相比会增加河道侵蚀的程度。因此，考虑多种SCM相互作用以及当地泥沙输运能力的多标准设计方法对于确保气候变化下的河道稳定性是必要的。
