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→Calculate the total depth of the practice, dT
* Step 5: Determine what the planting needs are and assign an appropriate depth of filter media, using the table above.
* Step 5: Determine what the planting needs are and assign an appropriate depth of filter media, using the table above.
* Step 6: Select an underdrain perforated pipe diameter (typically 100 or 200 mm), assign this as an 'embedded' depth equal to the pipe diameter. The perforated pipe depth can be made part of the active storage of the practice when a riser (standpipe and 90 degree coupling) are used to design the underdrain.
* Step 6: Select an underdrain perforated pipe diameter (typically 100 or 200 mm), assign this as an 'embedded' depth equal to the pipe diameter. The perforated pipe depth can be made part of the active storage of the practice when a riser (standpipe and 90 degree coupling) are used to design the underdrain.
* Step 7: Sum total depth of bioretention components, and compare to available space (i.e. depth) between the proposed surface grade and the seasonally high water table or top of bedrock elevations in the practice location.
* Step 7: Sum total depth of bioretention components, and compare to available space (i.e. depth) between the proposed surface grade and one (1) metre above the seasonally high water table or top of bedrock elevations in the practice location.
* Step 8: Adjust component depths to maintain a separation of 1.0 metre between base of the practice and seasonally high water table or top of bedrock elevation, or a lesser or greater value based on groundwater mounding analysis. See below and [[Groundwater]] for more information.<br>
* Step 8: Adjust component depths to maintain a separation of 1.0 metre between base of the practice and seasonally high water table or top of bedrock elevation, or a lesser or greater value based on groundwater mounding analysis. See below and [[Groundwater]] for more information.<br>
For practices without an underdrain in locations constrained in the vertical dimension, consider decreasing filter media depth (and supported plant types) and/or catchment impervious area.<br>
For practices without an underdrain in locations constrained in the vertical dimension, consider decreasing filter media depth (and supported plant types) and/or catchment impervious area.<br>