Increased intensity and frequency of floods raise concerns about the release and transport of contaminated soil and sediment to and from rivers and streams. To model these processes during flooding events, we developed an External Coupler in Python to link the Hydrologic Engineering Center-River Analysis System (HEC-RAS) 2D hydrodynamic model to the Water Quality Analysis Simulation Program (WASP). Accurate data transfer from a hydrodynamic model to a water quality model is critical. Our test results showed the External Coupler successfully linked HEC-RAS and WASP and addressed technical challenges in aggregating flow data and conserving mass during the flood event. We ran the coupled models for a 100-year flood event to calculate flood-induced transport of sediment-associated arsenic in Woodbridge Creek, NJ. Change in surface sediment and arsenic at the end of 48-h flood simulation ranged from a net loss of 13.5 cm to a net gain of 11.6 cm, and 16.2 to 2.9 mg/kg, respectively, per model segment, which demonstrates the capability of the coupled model for simulating sediment and contaminant transport in flood.

中文翻译：

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用于模拟洪水引起的土壤、沉积物和污染物迁移的耦合水动力 (HEC-RAS 2D) 和水质模型 (WASP)

洪水强度和频率的增加引起了人们对受污染土壤和沉积物在河流和溪流中的释放和运输的担忧。为了模拟洪水事件期间的这些过程，我们在 Python 中开发了一个外部耦合器，以将水文工程中心河流分析系统 (HEC-RAS) 二维水动力模型与水质分析模拟程序 (WASP) 联系起来。从水动力模型到水质模型的准确数据传输至关重要。我们的测试结果表明，外部耦合器成功地连接了 HEC-RAS 和 WASP，并解决了洪水事件期间聚合流量数据和保存质量的技术挑战。我们运行了 100 年洪水事件的耦合模型，以计算新泽西州伍德布里奇溪的洪水引起的沉积物相关砷的迁移。