A road cross$-$section is $8$ m wide $($from edge to edge of pavement$),$ with a $2\%$

crossfall slope from the centreline and is bounded by curbs. The Manning's $\text{'}n\text{'}$

for asphalt is $0\mathrm{.}013$ and the longitudinal slope of the roadway is $0\mathrm{.}02.$

a$)$ Calculate the water depth in the road cross$-$section when the flow is $1\mathrm{.}3$

$\frac{m^3}{s}.$

b$)$ The flood flow is expected to increase by $15\%$ with a change in climate.

Under these new conditions, calculate the water depth in the road cross$-$

section. Can the road "contain" the new climate$-$adjusted flow within the

roadway section?