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Line 35: − The following equations assume that infiltration occurs primarily through the base of the facility. − They may be easily applied for any shape and size of infiltration facility, in which the reservoir storage is mostly in an aggregate. − Line 45:
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Infiltration: Sizing and modeling (view source)
Revision as of 01:58, 12 September 2017
, 6 years ago→One dimensional infiltration
==One dimensional infiltration==
==One dimensional infiltration==
To calculate the required depth, where the area of the facility is constrained:
To calculate the required depth, where the area of the facility is constrained:
<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>
<h3>Drawdown time</h3>
<h3>Drawdown time</h3>
The design of infiltration facilities should be checked for [[drawdown time]]. Target drawdown time is between 48-72 hours. <br>
The following equation assumes that infiltration occurs primarily through the footprint of the facility.
To calculate the time (''t'') to fully drain 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}{q}</math>
<math>t=\frac{nd}{q}</math>