1,559
edits
Changes
Jump to navigation
Jump to search
Line 138:
Line 138:
For practices with no underdrain:Line 154:
Line 152:
→Determine the required surface area of the storage reservoir
==Determine the required surface area of the storage reservoir==
==Determine the required surface area of the storage reservoir==
* Step 13: Calculate the surface area of the storage reservoir, A<sub>r</sub> (m<sup>2</sup>) needed to capture the infiltration volume target for the design storm event <br>
* Step 13: Calculate the surface area of the storage reservoir, A<sub>r</sub> (m<sup>2</sup>) needed to capture the infiltration volume target for the design storm event: <math>A_{r}=V_{i}/[d_{i}+(f'\times D)]</math>
<math>A_{r}=V_{i}/[d_{i}+(f'\times D)]</math>
{{Plainlist|1=Where:
{{Plainlist|1=Where:
*V<sub>i</sub> = Infiltration volume target for the design storm event (m<sup>3</sup>), based on average annual water budgets for pre- and post-development scenarios, and the target of maintaining pre-development infiltration volume.
*V<sub>i</sub> = Infiltration volume target for the design storm event (m<sup>3</sup>), based on average annual water budgets for pre- and post-development scenarios, and the target of maintaining pre-development infiltration volume.
*D= Duration of design storm (h)<br>
*D= Duration of design storm (h)<br>
<br>
<br>
*Step 14: Calculate the required storage reservoir depth, d<sub>r</sub> (m):
<math>d_{r}=d_{i}\times 1/n_{r}'</math>
{{Plainlist|1=Where:
*d<sub>i</sub>' = Design infiltration water storage depth (m)
*n<sub>r</sub>' = Effective porosity of the storage reservoir fill material(s), depth-weighted mean of all components.
*f' = Design infiltration rate of the underlying native soil (m/h)<br>
==Calculate peak flow rates==
==Calculate peak flow rates==
* Step 13. Calculate the peak [[flow through perforated pipe|flow rate through the perforated pipe]],
* Step 14. Calculate the peak [[flow through perforated pipe|flow rate through the perforated pipe]],
* Step 14. Calculate the peak [[flow through media|flow rate through the filter media]],
* Step 16. Calculate the peak [[flow through media|flow rate through the filter media]],
* Step 15. Determine if downstream [[flow control]] is required to achieve hydrologic objectives.
* Step 17. Determine if downstream [[flow control]] is required to achieve hydrologic objectives.
===Calculating infiltration practice drainage in 1 dimension===
===Calculating infiltration practice drainage in 1 dimension===