Bull Creek Watershed has a reservoir with storage relationshipS = AH,where A is the area (...

Bull Creek Watershed has a reservoir with storage relationship

S = AH,

where A is the area (300 ac) and H is the depth or head of the reservoir in feet.

For simplicity, the area is assumed to be constant with depth. The outflow is governed by the equation

Q = 56.25H3/2,

where Q is in cfs. Route the storm hydrograph represented in the following table through the reservoir, using the fourth-order Runge-Kutta method.

The governing equation is

The fourth-order R-K equation will be used as shown in Equations 1 and 2. The assumption is made that H0 = 0 ft and Qout(H0) = 0 cfs. Values of Qin are interpolated as necessary, and values of Qout are found from the equation Q = 56.25H3/2.

Equation 1

Equation 2