An Integrated Hydrological-CFD Model for Estimating Bacterial Levels in Stormwater Ponds




Allafchi, Farzam
Valeo, Caterina
He, Jianxun
Neumann, Norman F.

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A hydrological model was integrated with a computational fluid dynamics (CFD) model to determine bacteria levels distributed throughout the Inverness stormwater pond in Calgary, Alberta. The Soil Conservation Service (SCS) curve number model was used as the basis of the hydrological model to generate flow rates from the watershed draining into the pond. These flow rates were then used as input for the CFD model simulations that solved the Reynolds-Averaged Navier-Stokes (RANS) equations with k-ɛ turbulence model. E. coli, the most commonly used fecal indicator bacteria for water quality research, was represented in the model by passive scalars with different decay rates for free bacteria and attached bacteria. Results show good agreement with measured data in each stage of the simulations. The middle of the west wing of the pond was found to be the best spot for extracting water for reuse because it had the lowest level of bacteria both during and after storm events. In addition, only one of the four sediment forebays was found efficient in trapping bacteria.



stormwater reuse, SCS curve number, CFD, fecal indicator bacteria, E. coli


Allafchi, F., Valeo, C., He, J. & Neumann, N.F. (2019). An Integrated Hydrological- CFD Model for Estimating Bacterial Levels in Stormwater Ponds. Water, 11(5), 1016.