The bioretention basin is a type of green infrastructure that treats stormwater runoff. However, there is a limited understanding of its treatment potential with different design configurations and limited capability to model bioretention systems. Current modeling practice fails to represent bacteria-mediated biochemical reactions that remove nitrogen. This study provides a reaction-based model of water quality treatment processes using multiple bacterial Monod kinetics under variably saturated flow conditions to predict the dynamics of nitrogen and organics in a bioretention system. The model was calibrated and validated against concentrations measured during an eight-month field monitoring program. Because the model simulates both basin hydrologic performance and biological treatment performance, it can be used to verify design guidelines by evaluating the response of the system to different design parameters. The model shows that nitrogen removal is enhanced by increasing bioretention basin volume and by setting an optimal value of hydraulic conductivity for subsurface infiltration.

生物滞留池是一种处理雨水径流的绿色基础设施。然而，对其具有不同设计配置的处理潜力和有限的生物滞留系统建模能力的了解有限。当前的建模实践无法代表去除氮的细菌介导的生化反应。本研究提供了一个基于反应的水质处理过程模型，该模型在可变饱和流动条件下使用多种细菌 Monod 动力学来预测生物滞留系统中氮和有机物的动力学。该模型根据为期八个月的现场监测计划期间测量的浓度进行了校准和验证。由于该模型同时模拟了流域水文性能和生物处理性能，它可用于通过评估系统对不同设计参数的响应来验证设计指南。该模型表明，通过增加生物滞留池体积和设置地下渗透的最佳水力传导率值，可以提高氮去除率。