In environmental impact assessments for large urban development projects, the Korean government requires analysis of stormwater
runoff before, during and after the projects. Though hydrological models are widely used to analyze and prepare for surface runoff
during storm events, accuracy of the predicted results have been in question due to limited amount of field data for model calibrations.
Intensive field measurements have been made for storm events between July 2015 and July 2016 at a sub-basin of the Gwanpyungcheon,
Daejeon, Republic of Korea using an automatic monitoring system and also additional manual measurements. Continuous
precipitation and surface runoff data used for utilization of SWMM model to predict surface runoff during storm events with improved
accuracy. The optimal values for Manning’s roughness coefficient and values for depression storage were estimated for pervious and
impervious surfaces using three representative infiltration methods; the Curve Number Methods, the Horton’s Method and the
Green-Ampt Methods. The results of the research is expected to be used more efficiently for urban development projects in Korea.