Considering the successful application of biological treatment in several restoration works in China, this study is aimed to complete the previous numerical modeling and practical observation of the stream restoration. The results obtained from the restoration of the Xuxi River, Wuxi City, China, show that the technology of bacteria offers new solution for restoring the polluted urban streams. Although a considerable increase in the concentration of nutrients may have enhanced the algae problem during the treatment, the Xuxi River is now clearer and contains aquatic life. In addition to showing good agreement with the observed data for selected calibrated parameters, the developed model also may be used for estimating missing values. Because of a lack of data, the model can only be validated using data collected from the Gankeng River, Shenzhen City. Based on the results, the model is able to fit the observed data under a broader range of field situations.