Changes

Orifices are simply holes which restrict the flow of water. They may be used at the bottom end of an LID practice to add some [[flow control]].

Orifices are simply holes which restrict the flow of water. They may be used at the bottom end of an LID practice to add some [[flow control]]:

<math>Q= B\times C_{d}\times A_{o}\sqrt{2\cdot g\cdot h}</math>

<math>Q= B\times C_{d}\times A_{o}\sqrt{2\cdot g\cdot h}</math>

{{Plainlist|1=Where:

{{Plainlist|1=Where:

*''B'' is the clogging factor (between 0.5 (for matured installation) and 1 (for a new perfectly performing BMP)),     

*''B'' is the clogging factor (between 0.5 (for matured installation) and 1 (for a new perfectly performing orifice)),     

*''C_d'' is the coefficient of discharge (usually 0.61 for a plate, or 0.8 for a pipe),  

*''C_d'' is the coefficient of discharge (usually 0.61 for a plate, or 0.8 for a pipe),  

*''A_o'' is the area of the orifice (m²),  

*''A_o'' is the area of the orifice (m²),