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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
, 7 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>