This research analyzed the changes of runoff by urban development with SCS-CN and HEC-HMS. Based on the developmental history of MuSim River of Cheongju-si, basin sluice model reflecting the changes of land using characteristics was established.
Each...
This research analyzed the changes of runoff by urban development with SCS-CN and HEC-HMS. Based on the developmental history of MuSim River of Cheongju-si, basin sluice model reflecting the changes of land using characteristics was established.
Each calibrated model with parameters are retained as catchment model for simulations of design rainfall, which 100, 200 and 500 year return period rainfalls are estimated with standard method of FARD.
The HEC-HMS-2000’s is also established in same way. These two groups of simulations in 1990’s and 2000’s are comparing a response of catchment in terms of flood peak and time to peak.
The results of this research can be abstracted as follows.
The first, in case of the land using changes by the development of MuShim River–Cheongju basin, the peak flood discharge and occurrence time of 2000s showed respectively the tendency of 100-year frequency (3%~78% increasement, 10.2~16% reduction), 200-year frequency (2.3%~18% increasement, 10.2%~16% reduction) and 500-year frequency (8.5% reduction~78% increasement, 10.3% reduction).
The second, runoff characteristics by housing site development of southeast area of Cheongju in 2018 were analyzed.
As the result, in comparison with 2000, peak flood discharge was increased by 100-year frequency (0.23~0.73%), 200-year frequency (0.24~0.66%), 500-year frequency (0.22~0.62%). The occurrence time of peak flood discharge was certain.
This study examines the effects of land use changing with long term observed data and suggests that the catchment model is useful tool to estimate the effects of land use change on flood characteristics.