*''K<sub>m</sub>'' is the hydraulic conductivity of the filter media (mm/hr),
*''K<sub>m</sub>'' is the hydraulic conductivity of the filter media (mm/hr),
*''A<sub>p</sub>'' is the area of the practice (m<sup>2</sup>),
*''A<sub>p</sub>'' is the area of the practice (m<sup>2</sup>),
*''Σ d<sub>z</sub>'' is the depth of ponding (mm),
*''Σ d<sub>z</sub>'' is the total depth of bioretention components over the perforated pipe (mm) (e.g. ponding/[[mulch]]/[[filter media]]/[[choker layer]]),
*''d<sub>m</sub>'' is the depth of the filter media (mm), and
*''d<sub>m</sub>'' is the depth of the filter media (mm), and