G$\mathrm{.}3.$ You are an engineer working on sewer designs for a new residential subdivision being added to an existing city. The sanitary sewer servicing the subdivision will pick up the wastewater flow from a total of $1300$ new homes. Annual average wastewater flow is estimated at $400$ gpd per dwelling.

It is proposed by the developer that this subdivision wastewater flow be put into an existing sewer main nearby rather than paying for a new force main to pump the water to the treatment plant. The existing sewer main is a $42-$inch reinforced concrete pipe with a Manning$$s n$=0\mathrm{.}013.$ Its slope is $0\mathrm{.}00025$ ft$/$ft$.$ The Public Works Department has determined the existing peak flow in the line is $5\mathrm{.}2$ MGD$.$

For all calculations, assume n is constant for all depths of flow. A peaking factor of $2\mathrm{.}5$ should be used.

G$\mathrm{.}3.$a$.$ What is the depth of flow $($inches$)$ in the existing sewer main under current peak flow conditions?

G$\mathrm{.}3.$b$.$ What is the peak flow rate $($gpd$)$ from the additional development?

G$\mathrm{.}3.$c$.$ What will depth $($inches$)$ in the existing sewer main be after connecting the additional subdivision?

G$\mathrm{.}3.$d$.$ Based on the city$$s requirement that the peak flow must fill the pipe no more than $2/3$ full, is the developer$$s proposal to add the additional subdivision to the existing main allowed? $($Yes$/$No$)$