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→Size a bioretention cell receiving flows directly to the storage reservoir for a constrained depth
==Size a bioretention cell receiving flows directly to the storage reservoir for a constrained depth==
==Size a bioretention cell receiving flows directly to the storage reservoir for a constrained depth==
If there is a constraint to the depth (''d<sub>T</sub>'') of the practice, calculate the required practice footprint area (''A<sub>p</sub>''), as:
If there is a constraint to the depth (''d<sub>T</sub>'') of the practice, calculate the required storage reservoir footprint area (''A<sub>r</sub>''), as:
<math>A_{p}=\frac{A_i\times i\times D}{(d_{T}'\times n')+(f'\times D)}</math>
<math>A_{r}=\frac{A_i\times i\times D}{(d_{r}\times n')+(f'\times D)}</math>
{{Plainlist|1=Where:
{{Plainlist|1=Where:
*''A<sub>p</sub>'' = Area of the infiltration practice (m<sup>2</sup>)
*''A<sub>r</sub>'' = Area of the infiltration practice storage reservoir (m<sup>2</sup>)
*''A<sub>i</sub>'' = Catchment impervious area (m<sup>2</sup>)
*''A<sub>i</sub>'' = Catchment impervious area (m<sup>2</sup>)
*''D'' = Duration of design storm (h)
*''D'' = Duration of design storm (h)
*''f''' = [[design infiltration rate]] (m/h)
*''f''' = [[design infiltration rate]] (m/h)
*''n''' = Effective porosity of the fill materials within the active storage component(s) of practice, depth-weighted mean
*''n''' = Effective porosity of the fill materials within the active storage component(s) of practice, depth-weighted mean
*''d<sub>T</sub>''' = Total depth available between the elevation of the invert of the underdrain perforated pipe and one (1) metre above the seasonally high water table or top of bedrock (m) or other value determined to be suitable through groundwater mounding analysis.}}<br>
*''d<sub>r</sub>'' = Storage reservoir depth, based on depth available between the elevation of the invert of the underdrain perforated pipe and one (1) metre above the seasonally high water table or top of bedrock (m) or other value determined to be suitable through groundwater mounding analysis.}}<br>
If R is greater than 20, consider decreasing catchment impervious area (A<sub>i</sub>) by draining less area to the practice.
If R is greater than 20, consider decreasing catchment impervious area (A<sub>i</sub>) by draining less area to the practice.