Difference between revisions of "Talk:Infiltration"

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(Created page with "'''The material pasted here has been retained for archival purposes only.''' Infiltration tests must be undertaken at the location, depth and with a...")
 
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===Example===
Where the mean infiltration rate measured at the proposed bottom elevation of the BMP is 30 mm/hr, and the mean infiltration rate measured in an underlying soil horizon within 1.5 m of the bottom is 12 mm/h:
:<math>ratio=\frac{q_{bottom}}{min\ q_{within 1.5m}}\ =\ \frac{30}{12}\ =2.5</math>
From the table the SCF is 3.5, and the design infiltration rate can be calculated:
:<math>q'=\frac{q}{SCF}\ =\ \frac{30}{3.5}=\ 8.6\ mm/hr</math>

Revision as of 21:35, 18 March 2018

The material pasted here has been retained for archival purposes only.

Infiltration tests must be undertaken at the location, depth and with a head of water that replicates the proposed design.

Suggested safety factors to be applied to measured percolation rate when designing infiltration facilities
Catchment area Consequence of failure
No damage or inconvenience Minor damage or inconvenience to external structures (e.g. ponding in parking lot) Significant damage to buildings or infrastructure (e.g. flooding damage)
<100 m2 1.5 2 10
100 - 1000 m2 1.5 3 10

Example[edit]

Where the mean infiltration rate measured at the proposed bottom elevation of the BMP is 30 mm/hr, and the mean infiltration rate measured in an underlying soil horizon within 1.5 m of the bottom is 12 mm/h:

From the table the SCF is 3.5, and the design infiltration rate can be calculated: