The stormwater management model (SWMM) was adapted and calibrated to Jinan, a typical piedmont city in China, to verify the large-scale applicability of the model to piedmont cities. Fourteen storms were used for model calibration and validation. The calibrated model predicted the measured data with satisfactory accuracy and reliability. A sensitivity analysis was then conducted to evaluate the impact of the model parameters; it showed that: (1) the model outputs were most sensitive to imperviousness and conduit roughness; and (2) infiltration parameters and depression storage play an important role in total runoff and peak flow. The urban drainage system of Jinan was assessed using urban design storms with the calibrated model, and the effects of engineered flood control measures were evaluated. The overall results demonstrate that SWMM is applicable on a large scale to piedmont cities.