Hydrologic model for rainfall-runoff analysis can be divided into two parts; the one with consideration of spatial variability of parameter called distributed model and lumped model which ignores spatial variability. However, distributed model is becoming more popular because it is one that can be relied on compared to lumped model which simply has benefit in convenience on established calculator.
In this research, based on three rainfall event in Changchon, which is the application basin, estimation of runoff was conducted with Vflo and HEC-HMS model to find out which design of flood gate is appropriate.
As a result of this estimation, Snyder's unit hydrograph method coefficient of correlation (CC) and error in volume (EV) has correlation with observed value but there was less relativity in error in peak (EP). Also, comparison of Snyder's UH method and Vflo showed that Vflo model has higher relation in CC and EP. On the other hand, Snyder Method has higher relation with EV. Therefore, if a project requires rainfall-runoff analysis in unmeasured basin, using both distributed model and lumped model would give more accurate and trustworthy result.