8,254
edits
Changes
Jump to navigation
Jump to search
mLine 1:
Line 1:
Line 11:
Line 11:
→Trapezoidal channel
These sizing equations are suggested for use in calculating the capacity of swales which have a larger proportion of surface flow. i.e. grass swales, rather than [[bioswales]].
These sizing equations are suggested for use in calculating the capacity of swales which have a larger proportion of surface flow. i.e. grass swales, rather than [[bioswales]]. <br>
In many cases the length of swale required will exceed the available space, so that an underground [[infiltration trenches|infiltration trench]] or a [[Dry ponds| dry pond]] will be a preferred solution.
===Triangular channel===
===Triangular channel===
<math>L=\frac{360,000Q_{p}}{\left\{ b+2.388\left[\frac{Q_{p}n}{\left(2\sqrt{1+m^{2}-m}\right)S^{\frac{1}{2}}}\right ]^{\frac{3}{8}}\sqrt{1+m^{2}} \right \}q}</math>
<math>L=\frac{360,000Q_{p}}{\left\{ b+2.388\left[\frac{Q_{p}n}{\left(2\sqrt{1+m^{2}-m}\right)S^{\frac{1}{2}}}\right ]^{\frac{3}{8}}\sqrt{1+m^{2}} \right \}q}</math>
{Plainlist|1=Where:
{{Plainlist|1=Where:
*L = length of swale in m
*''L'' = length of swale in m
*Q<sub>p</sub> = peak flow of the storm to be controlled, in m<sup>3</sup>/s
*''Q<sub>p</sub>'' = peak flow of the storm to be controlled, in m<sup>3</sup>/s
*m = swale side slope (dimensionless)
*''m'' = swale side slope (m/m)
*S = the longitudinal slope (dimensionless)
*''S'' = the longitudinal slope (m/m)
*n = Manning's coefficeint (dimensionless)
*''n'' = Manning's coefficient (dimensionless)
*b = bottom width of trapezoidal swale, in m.}
*''b'' = bottom width of trapezoidal swale, in m.}}