A concrete culvert $($n $=0\mathrm{.}013)$ will be used to pass a design discharge of $50$ cfs$.$ The slope of the culvert

$($So$)$ is $0\mathrm{.}005.$

Assuming that a rectangular box culvert with a width $($b$)$ of $4\mathrm{.}0$ feet and a depth $($d$)$ of $4\mathrm{.}0$ feet is used,

determine the following:

a$.$ The normal depth yn $($in feet$).$ State whether the normal depth is within the barrel or is

greater than the barrel depth.

b$.$ The critical depth yc $($in feet$).$ State whether the critical depth is within the barrel or is

greater than the barrel depth.

c$.$ Is the channel slope mild or steep if a rectangular box culvert is used?

Assuming that a circular box culvert with a diameter $($D$)$ of $4\mathrm{.}0$ feet is used, determine the following:

a$.$ The normal depth yn $($in feet$).$ State whether the normal depth is within the barrel or is

greater than the barrel depth.

b$.$ The critical depth yc $($in feet$).$ State whether the critical depth is within the barrel or is

greater than the barrel depth.

c$.$ Is the channel slope mild or steep if a circular culvert is used?