Line 45: |
Line 45: |
| ==To calculate the required depth, where the area of the facility is constrained (1D)== | | ==To calculate the required depth, where the area of the facility is constrained (1D)== |
| <math>d=\frac{D\left[\left( \frac{I}{P} \right )i-q \right]}{n}</math> | | <math>d=\frac{D\left[\left( \frac{I}{P} \right )i-q \right]}{n}</math> |
− |
| |
− | ==To calculate the require facility area or footprint where the depth is constrained (1D)==
| |
− | <math>P=\frac{IiD}{nd+qD}</math>
| |
− |
| |
− | ==Infiltration of surface ponding time==
| |
− | The following equation assumes that infiltration occurs primarily through the footprint of the facility.
| |
− | It is best applied to calculate the limited duration ponding on the surface of [[bioretention cells]], [[bioswales]] and [[enhanced grass swales]].
| |
− | To calculate the time (''t'') to fully drain the facility through the footprint area only:
| |
− | <math>t=\frac{nd}{K}</math>
| |
− |
| |
| ==To calculate required depth (3D)== | | ==To calculate required depth (3D)== |
| [[file:Hydraulic radius.png|thumb|Three footprint areas of 9 m<sup>2</sup>.<br> | | [[file:Hydraulic radius.png|thumb|Three footprint areas of 9 m<sup>2</sup>.<br> |
Line 69: |
Line 59: |
| | | |
| (The rearrangement to calculate the required footprint area of the facility for a given depth is not available at this time. Elegant submissions are invited.) | | (The rearrangement to calculate the required footprint area of the facility for a given depth is not available at this time. Elegant submissions are invited.) |
| + | |
| + | ==To calculate the require facility area or footprint where the depth is constrained (1D)== |
| + | <math>P=\frac{IiD}{nd+qD}</math> |
| + | |
| + | ==Infiltration of surface ponding time== |
| + | The following equation assumes that infiltration occurs primarily through the footprint of the facility. |
| + | It is best applied to calculate the limited duration ponding on the surface of [[bioretention cells]], [[bioswales]] and [[enhanced grass swales]]. |
| + | To calculate the time (''t'') to fully drain the facility through the footprint area only: |
| + | <math>t=\frac{nd}{K}</math> |
| + | |
| | | |
| ==Drawdown time== | | ==Drawdown time== |