QUESTION $3[5$ Marks$]$

A $3450$ km$2$ watershed receives $98$ cm of precipitation in one year. The average flow of the river

draining the watershed is $32\mathrm{.}8$ m$3$

$/$sec$.$ Infiltration is estimated to be $4\mathrm{.}9$ x $10-7$

cm$/$sec and

evapotranspiration is estimated to be $38$ cm$/$yr$.$

a$)$ Calculate the change in water storage in the watershed over one year. $[3$ marks$]$

b$)$ Runoff coefficient can be defined as the ratio of runoff $($in this case the river flow$)$ to the

rainfall $($both in cm$).$ Compute the runoff coefficient for this watershed. $[2$ marks$]$