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*Step 1: Determine what the planting needs are and assign appropriate depth of media, using the table above. *Step 2: Select an underdrain pipe diameter (typically 100 - 200 mm), assign this as an 'embedding' depth. *Step 3: Calculate the maximum possible storage reservoir depth beneath the pipe (''d<sub>s</sub>''):<math>d_{s}=f'\times38.4</math>{{Plainlist|1=Where:*''f''' = Design infiltration rate in mm/hr, and*38.4 comes from multiplying desired drainage time of 96 hours by void ratio of 0.4}}===Additional step for system without underdrain===*Step 4: Determine maximum permissible ponding depth (''d<sub>p</sub>''):<math>d_{p}=f'\times19.2</math>{{Plainlist|1=Where:*''f''' = Design infiltration rate in mm/hr, and*19.2 comes from multiplying desired drainage time of 48 hours by void ratio of 0.4. Note that conceptually the drainage of the ponded area is limited by ex-filtration at the base of the practice.}}* Step 5: Sum total depth of bioretention, and compare to available space above water table and bedrock. Adjust if necessary.==Calculate the remaining dimensions==* Step 6: Multiply the depth of each separate component by the void ratio and then sum the total to find the 1 dimensional storage (in mm).* Step 7: Calculate the required total storage (m<sup>3</sup>):<math>Storage=RVC_T\times A_c\times C\times 0.1</math>{{Plainlist|1=Where:*''RVC<sub>T</sub>'' is the Runoff volume control target (mm),*''A<sub>c</sub>'' is the catchment area (Ha), *''C'' is the runoff coefficient of the catchment area, and* 0.1 is the units correction between m<sup>3</sup> and mm.Ha.}}* Step 8. Divide required storage (m<sup>3</sup>) by the 1 dimensional storage (in m) to find the required footprint area (''A<sub>p</sub>'') for the bioretention in m<sup>2</sup>. * Step 9. Calculate the peak flow rate (''Q<sub>p</sub>'', in L/s) through the filter media:----
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==Calculate the maximum overall depth==
==Calculate the maximum overall depth==