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Line 8: − Determine if there is a constraint to the depth (''d<sub>T</sub>'') of the bioretention practice: − + + + + + + + + + + + + + + + + − |-+ − !colspan="2" style="text-align: center;"|Then+ − |- − |To calculate the require facility area or footprint where the depth is constrained: − − |To calculate the required depth, where the area of the facility is constrained: − |}+
→Size a bioretention cell for constrained depth
==Size a bioretention cell for constrained depth==
==Size a bioretention cell for constrained depth==
{{:Depth to GW}}
{{:Depth to GW}}
|'''or''' if the land area is limited, determine the I/P ratio::<math>R=\frac{A_{c}}{A_{p}}</math>
If there is a constraint to the depth (''d<sub>T</sub>'') of the bioretention practice calculate the require facility area or footprint where the depth is constrained, as:
<math>A_{p}=\frac{IiD}{V_{R}d+f'D}</math>
{{Plainlist|1=Where:
*''D'' = Duration of design storm in hrs
*''i'' = Intensity of design storm in mm/hr
*''f''' = [[design infiltration rate]] in mm/hr
*''V<sub>R</sub>'' = Void ratio (porosity), as measured (or default to 0.35 for all aggregates)
*''R'' = Ratio of catchment area (''A<sub>c</sub>'') to BMP footprint area (A<sub>p</sub>).
*''A<sub>p</sub>'' = Area of the infiltration practice in m<sup>2</sup>
*''A<sub>c</sub>'' = Catchment area in m<sup>2</sup>
*''d<sub>T</sub>'' = Total depth of the infiltration practice in m.}}
==Size a bioretention cell for constrained ground area==
If the land area is limited, determine the ratio:
:<math>R=\frac{A_{c}}{A_{p}}</math>
{{Plainlist|1= Where:
{{Plainlist|1= Where:
*''R'' = Ratio of catchment area (''A<sub>c</sub>'') to BMP footprint area (A<sub>p</sub>) syn. I/P ratio.
*''R'' = Ratio of catchment area (''A<sub>c</sub>'') to BMP footprint area (A<sub>p</sub>) syn. I/P ratio.
*''A<sub>p</sub>'' = Area of the infiltration practice in m<sup>2</sup>
*''A<sub>p</sub>'' = Area of the infiltration practice in m<sup>2</sup>
*''A<sub>c</sub>'' = Catchment area in m<sup>2</sup>}}
*''A<sub>c</sub>'' = Catchment area in m<sup>2</sup>}}
Calculate the required depth (d<sub>T</sub>), as:
<math>A_{p}=\frac{IiD}{V_{R}d+q'D}</math>
<math>d=\frac{D\left[Ri-q'\right]}{V_{R}}</math>
<math>d=\frac{D\left[Ri-q'\right]}{V_{R}}</math>
{{#widget:WolframAlpha|id=88d135fd5507a36a9770deaa8106c975}}
{{#widget:WolframAlpha|id=88d135fd5507a36a9770deaa8106c975}}
{{Plainlist|1=Where:
{{Plainlist|1=Where:
*''D'' = Duration of design storm in hrs
*''D'' = Duration of design storm in hrs