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*Step 1: Determine what the planting needs are and assign appropriate depth of media, using the table above.  
*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. *Note that this component does not apply if a downstream riser is being used.   
*Step 2: Select an underdrain pipe diameter (typically 100 - 200 mm), assign this as an 'embedding' depth. *Note that this component does not apply if a downstream riser is being used.   
*Step 3: Calculate the maximum possible storage reservoir depth beneath the pipe (''d<sub>s</sub>''):
*Step 3: Calculate the maximum possible storage reservoir depth beneath the pipe (''d<sub>s, max</sub>''):
<math>d_{s}=\frac{f'\times 96}{0.4}</math>
<math>d_{s, max}=\frac{f'\times '}{0.4}</math>
{{Plainlist|1=Where:
{{Plainlist|1=Where:
*''f''' = Design infiltration rate (mm/hr), and
*''f''' = Design infiltration rate (mm/hr), and
*96 = [[Drainage time]] (hrs)
*''t'' = [[Drainage time]] (hrs), e.g. 96 hours, check local regulations for drainage time requirements. 
*0.4 = Void ratio of [[reservoir gravel|clear stone]]}}
*''0.4'' = Void ratio of [[reservoir gravel|clear stone]]}}


===Additional step for system without underdrain===
===Additional step for system without underdrain===

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