This paper presents a three-dimensional CFD based hydro-environmental model that simulates fate and transport of bacteria in water bodies. The model numerically solves unsteady incompressible Reynolds-Averaged Navier-Stokes equations on a structured grid. Free-floating and particle-attached bacteria were modelled separately regarding both fate and transport. Therefore, a sediment transport model was integrated into the main model in order to model particle-attached bacteria transport. In addition, Volume of Fluid approach was implemented to capture the water surface movements. Wind effect was also considered in the modelling using shear stress on the water surface. Since stormwater reuse is the source of some public health concerns, a stormwater pond was chosen as the test case for the model. The model was applied to simulate the distribution of bacterial indicator organisms in the Inverness Stormwater Pond in Calgary, Alberta, which is a large T-shaped pond with several inlets and outlets. The bacteria distribution in the pond was simulated for three rain events that occurred in the area. In six locations of the pond the modelled bacteria distribution was compared to collected data using non-dimensional bacteria concentrations. The comparison showed good agreement and indicated that the middle of the pond, close to the surface had the lowest levels of bacteria and thus, was considered the optimal location for withdrawal for reusing pond water. Furthermore, planting a tree barrier on the north bank of the West wing of the pond was shown to mitigate bacteria transport away from the inlets into the pond body and substantially decrease the risk of contamination at the optimal water withdrawal location.

本文提出了一个基于三维 CFD 的水环境模型，该模型模拟了水体中细菌的命运和运输。该模型在结构化网格上对不稳定的不可压缩 Reynolds-Averaged Navier-Stokes 方程进行数值求解。自由漂浮和附着颗粒的细菌分别在命运和运输方面建模。因此，将泥沙输运模型整合到主要模型中，以模拟颗粒附着细菌的输运。此外，还实施了流体体积方法来捕捉水面运动。在使用水面剪切应力的建模中还考虑了风效应。由于雨水再利用是一些公共卫生问题的根源，因此选择了雨水池作为模型的测试案例。该模型用于模拟阿尔伯塔省卡尔加里因弗内斯雨水池中细菌指示生物的分布，该池是一个具有多个入口和出口的大型 T 形池塘。针对该地区发生的三个降雨事件模拟了池塘中的细菌分布。在池塘的六个位置，模拟的细菌分布与使用无量纲细菌浓度收集的数据进行了比较。比较显示出良好的一致性，并表明靠近水面的池塘中部的细菌水平最低，因此被认为是重新利用池塘水的最佳取水位置。此外，