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==Calculate the total depth of the practice, d<sub>T</sub>==
==Calculate the total depth of the practice, d<sub>T</sub>==
* Step 10: Determine what the planting needs are and assign an appropriate depth of filter media, using the table above.
* Step 10: Determine what the planting needs are and assign an appropriate depth of filter media, using the table above.
* Step 11: 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 11: 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 infiltration water storage of the practice when a riser (standpipe and 90 degree coupling) are used to design the underdrain.
* Step 12: 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 elevation in the practice location.
* Step 12: Sum total depth of bioretention components, and compare to available space (i.e. depth) between the elevations of the proposed surface grade and one (1) metre above the seasonally high water table or top of bedrock in the practice location.
* Step 13: Adjust component depths to maintain a separation of one (1) metre between the base of the practice and the 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 13: Adjust component depths to maintain a separation of one (1) metre between the base of the practice and the 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>