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<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 0.35 may be assumed (i.e. void ratio 35%). </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>Bioretention facilities are usually between 0.5 m and 1.25 m deep, owing to construction considerations. Determine the maximum available depth (c<sub>c max</sub>) from the site constraints. The [[Infiltration]] page has some of these listed. </li>
<li>Bioretention facilities are usually between 0.5 m and 1.25 m deep, owing to construction considerations. Determine the maximum available depth (c<sub>c max</sub>) from the site constraints. The [[Infiltration]] page has some of these listed. </li>
<li>Identify the duration (D) and intensity (i) of design storm(s). </li></ul>
<li>Identify the duration (D) and intensity (i) of design storm(s). </li></ul>