$8\mathrm{.}6\mathrm{.}3.$ An overflow spillway for a small water supply reservoir needs to be designed. The spillway must be able to pass a design flood flow of $935$ cfs$.$ However, flooding upstream of the reservoir will occur if the water depth in the reservoir rises above the spillway crest $($the normal reservoir level$)$ by more than $4\mathrm{.}2$ ft $.$ Can the design be accomplished if the spillway width is limited by site conditions to roughly $30$ ft $?$ li not, suggest some alternatives that would meet the existing design conditions. Assume an

approximate spillway coefficient of $3\mathrm{.}5.$

The correct answer is : The design flow can't be met under these conditions: A little longer spillway is needed or a more efficient spillway $($C$).$