Urbanization and climate change produce distortions in urban water circulation. This issue can be resolved using a stormwater management technique called Low Impact Development (LID), which mimics natural processes and restores the hydrological state ...
Urbanization and climate change produce distortions in urban water circulation. This issue can be resolved using a stormwater management technique called Low Impact Development (LID), which mimics natural processes and restores the hydrological state as it was before development. This study aims to evaluate the performance of a LID facility and calculate the runoff reduction and delay effect. The test-bed is a green wall of the Korea GI & LID Center. Scenarios for 30 mm/hr, 50 mm/hr, and 70 mm/hr were set based on the percentile of rainfall events from 2012 to 2021 in Geumjeong-gu, Busan. By setting an impervious surface as the control group, runoff reduction was found to be 91%~94% of 30 mm/hr, 50 mm/hr, and 70 mm/hr. The total outflow time increased by 47, 88, and 58 minutes, respectively, demonstrating the effect of reduced runoff and delayed time. A storm water management model (SWMM) was constructed to evaluate this effect quantitatively. Verification and correction were done using the experiment results. R2 was 0.96~0.98 for the test and 0.93~0.94 for the correction. This paper thus verified the retention effectiveness performance of a green wall and analyzed its quantitative effect through a SWMM. The study findings can be used as a guideline to test parameter-wise hydrological performance of the model.