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==Example==
 
==Example==
A curb cut of 3 m is proposed as an inlet for an offline [[Bioretention|bioretention cell]] receiving runoff from an adjacent roadway. The gutter and the curb are made from smooth concrete with Manning's 'n' = 0.013. The x-slope is 3% and the longitudinal slope of the road is 2%. The 1 in 25 year design storm produces a peak flow of 0.08 m<sup>3</sup>/s.  
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Three (3) curb cut inlets of 1 m width each, representing a total curb cut width of 3 m, are proposed for an offline [[Bioretention|bioretention cell]] receiving runoff from an adjacent roadway. The gutter and the curb are made from smooth concrete with Manning's 'n' = 0.013. The x-slope is 3% and the longitudinal slope of the road is 2%. The 1 in 25 year design storm produces a peak flow of 0.08 m<sup>3</sup>/s.  
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The width of inlet to capture 100% of this flow is:
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The total width of curb cut inlets required to capture 100% of this flow is:
 
<math>W_T=0.817\times(0.08)^{0.42}\times(0.02)^{0.3}\left (\frac{1}{0.013\times0.03}\right)^{0.6}=9.71\ m</math>
 
<math>W_T=0.817\times(0.08)^{0.42}\times(0.02)^{0.3}\left (\frac{1}{0.013\times0.03}\right)^{0.6}=9.71\ m</math>
 
   
 
   
The proportion of water entering the bioretention cell under these flow conditions would be:
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The proportion of water entering the bioretention cell under peak flow conditions during the design storm event would be:
 
<math>R_c=1-\left ( 1-\frac{3}{9.71} \right )^{1.8}= 0.48</math>
 
<math>R_c=1-\left ( 1-\frac{3}{9.71} \right )^{1.8}= 0.48</math>
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48% of the 0.08 m<sup>3</sup>/s (i.e. 0.038 m<sup>3</sup>/s) would enter the bioretention cell through the inlet as designed.
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So 48% of the 0.08 m<sup>3</sup>/s (i.e. 0.038 m<sup>3</sup>/s) would enter the bioretention cell through the inlets as designed.
    
==Curb cuts gallery==
 
==Curb cuts gallery==

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