Bioretention cells should be sized to accommodate runoff from approximately 5 to 20 times the footprint area of the facility. i.e. I:P ratio of 5 to 20.
If additional storage volume is desired beneath an underdrain pipe, this may be sized as an [[Infiltration:_Sizing_and_modeling|infiltration trench]].
[[Bioretention:_Sizing_and_modeling]]
If additional storage volume is desired beneath an underdrain pipe, this may be sized as an [[Infiltration:_Sizing_and_modeling|infiltration trench]].