Stormwater Management Model (SWMM5) and InfoSWMM Information for watershed water quality, hydrology and hydraulics modelers #INFOSWMM Simple SI Unit Model for SWMM5 LID with 100 mm Rainfall. Reading this blog and using the embedded SWMM 5 example file, you will run a simple SI unit model based on factors of 1 and 10. The LID (Bio-Retention Cell) is designed to have zero outflows, Figure 1…