Difference between revisions of "Bioretention: Sizing and modeling"

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<ol>
<ol>
<li>Gather input data:  
<li>Input data:  
<ul>
<ul>
<li>The applicable infiltration coefficient (q) is calculated by applying the safety factor to the [[Infiltration: Testing|measured infiltration rate]].</li>
<li>The applicable infiltration coefficient (q) is calculated by applying the [[safety factor]] to the [[Infiltration: Testing|measured infiltration rate]].</li>
<li>Determine the drainage catchment area (A<sub>D</sub>), and outline the location of the bioretention facility. To begin with, budget for at least 10% of the contributing impervious area to be required for the BMP. </li></li>
<li>Determine the drainage catchment area (A<sub>D</sub>), and outline the location of the bioretention facility. To begin with, budget for at least 10% of the contributing impervious area to be required for the BMP. </li></li>
<li>Unless the biomedia fill material has been tested and certified otherwise, a porosity value (V<sub>r</sub>) of 0.4 may be assumed (i.e. void ratio 40%). </li>
<li>Unless the biomedia fill material has been tested and certified otherwise, a porosity value (V<sub>r</sub>) of 0.4 may be assumed (i.e. void ratio 40%). </li>

Revision as of 17:48, 10 July 2017

  1. Input data:
    • The applicable infiltration coefficient (q) is calculated by applying the safety factor to the measured infiltration rate.
    • Determine the drainage catchment area (AD), and outline the location of the bioretention facility. To begin with, budget for at least 10% of the contributing impervious area to be required for the BMP.
    • Unless the biomedia fill material has been tested and certified otherwise, a porosity value (Vr) of 0.4 may be assumed (i.e. void ratio 40%).
    • Bioretention facilities are usually between 0.5 m and 1.25 m deep, owing to construction considerations. Determine the maximum available depth (cc max) from the site constraints. The Infiltration page lists these.
    • Identify the duration (D) and intensity (i) of design storm(s).
  2. Calculate the required area

Download .xlsx calculation tool