Question $2$Question $3$

An inflow hydrograph is given for a reservoir that has a weir spillway outflow structure. The flow

through the spillway is governed by the equation,

$Q=3\mathrm{.}75L{y}^{\frac{3}{2}}(cfs)$

Where $L$ is the length of the weir and $y$ is the heigh of the water above the spillway crest. The storage in

the reservoir is governed by$,$

$S=300y(ac-ft)$

Using $t=12hrs,L=15ft$ and $S_0=Q_0=0,$ route the inflow hydrograph through the reservoir using the

Storage Indication $(($Modified Puls$))$ Method.

Given the following $2-$hr unit hydrograph, calculate the $1-$hr unit hydrograph. Then back calculate and

find the $2-$hr unit hydrograph to prove that the method of calculation is accurate.

Graph both unit hydrographs against time on the same plot.