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*Step 1: Determine what the planting needs are and assign appropriate depth of media.  
 
*Step 1: Determine what the planting needs are and assign appropriate depth of media.  
 
*Step 2: Decide on the underdrain pipe diameter.  
 
*Step 2: Decide on the underdrain pipe diameter.  
*Step 3: Determine maximum possible storage reservoir depth beneath the pipe (''d<sub>S</sub>''):
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*Step 3: Determine maximum possible storage reservoir depth beneath the pipe (''d<sub>s</sub>''):
<math>d_{S}=f'\times38.4</math>
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<math>d_{s}=f'\times38.4</math>
 
{{Plainlist|1=Where:
 
{{Plainlist|1=Where:
 
*''f''' = Design infiltration rate in mm/hr, and
 
*''f''' = Design infiltration rate in mm/hr, and
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===Additional step for system without underdrain===
 
===Additional step for system without underdrain===
*Step 4: Determine maximum permissible ponding depth (''d<sub>P</sub>''):
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*Step 4: Determine maximum permissible ponding depth (''d<sub>p</sub>''):
<math>d_{P}=f'\times19.2</math>
+
<math>d_{p}=f'\times19.2</math>
 
{{Plainlist|1=Where:
 
{{Plainlist|1=Where:
 
*''f''' = Design infiltration rate in mm/hr, and
 
*''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.}}
 
*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 necesary.  
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* Step 5: Sum total depth of bioretention and compare to available space above water table and bedrock. Adjust if necesary.
    
==Calculate the remaining dimensions==
 
==Calculate the remaining dimensions==
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