	Product(s):	PondPack
	Version(s):	V8i, CONNECT Edition
	Area:	Modeling

Problem

When trying to compute PondMaker step 2, the following user notification appears:

"The target peak X ft³/s is greater than the inflow hydrograph peak flow, Y ft³/s. You must specify a target at or below the peak flow of the inflow hydrograph."

Solution

This message occurs when the postdevelopment peak flow is greater than the predevelopment target peak flow. In short, it indicates that a pond is not needed to attenuate the postdevelopment inflow because is is already lower than predevelopment conditions.

The idea behind PondMaker is the design a pond to attenuate the postdevelopment peak to be equal to or less than the predevelopment peak conditions. Normally after development, the land is less porous and the peak flow is higher.

If you believe that these flow values are correct, and the decrease is due to some undetained (bypassed) flow that needs to be compensated for, see: Accounting for bypassed (undetained) flow in PondMaker

If you believe that these flow values are not correct, you can "fix" this by adjusting the conditions so that the postdevelopment peak is greater than the predevelopment target peak:

Confirm that the correct scenarios and options are selected in Step 1 of PondMaker
Confirm that the correct conditions are depicted in each of the respective scenarios - change your active scenario to the postdevelopment, examine the catchment properties, then change the active scenario to the predevelopment and examine the catchment properties. Catchment information is stored in the Hydrology alternative.

"The target peak is greater the inflow hydrograph peak..."

Problem

Solution

See Also