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Line 32:
Line 32: − For example, where the mean infiltration rate measured at the proposed bottom elevation of the BMP is 30 mm/h, and the mean infiltration rate measured in an underlying soil horizon within 1.5 metres of the bottom is 12 mm/h:+
→Example
===Example===
===Example===
Where the mean infiltration rate measured at the proposed bottom elevation of the BMP is 30 mm/h, and the mean infiltration rate measured in an underlying soil horizon within 1.5 metres of the bottom is 12 mm/h:
:<math>ratio=\frac{q_{bottom}}{min\ q_{within 1.5m}}\ =\ \frac{30}{12}\ =2.5</math>
:<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:
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>
:<math>q'=\frac{q}{SCF}\ =\ \frac{30}{3.5}=\ 8.6 mm/hr</math>