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| ==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> |
− | For practices with no underdrain:
| |
− | <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. |
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| *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> |
| + | |
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| ==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. |
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| ===Calculating infiltration practice drainage in 1 dimension=== | | ===Calculating infiltration practice drainage in 1 dimension=== |