Sub Areas and Pond Surface Area

[MEM1]

Peter

I am modeling several sub areas and ponds. Does the pond surface area need to be added to the sub area size? Or, does hydrocad recognize the pond surface area when a pond node is added to the model? If hydrocad recognizes the pond surface area when a pond node is added, what curve number is being used in the runoff calculations?

Example:
Sub Area Size = 5 acres
Pond Surface Area = 1 acres

Do I add my sub area size at 6 acres with a weighted curve number, or do I add a sub area node @ 5 acres with appropriate curve number and a pond node with stage storage table?

Thanks in advance

Scott

 

[psmart]

In order to allow for the rainfall on the surface of a pond, you need to include the area in an adjacent subcatchment, or model it as a separate subcatchment with a Tc=0. This allows instantaneous "runoff" of the rainfall into the pond's storage volume.

For details see

http://www.hydrocad.net/pond.htm

Peter Smart
HydroCAD Software

http://www.hydrocad.net

 

[MEM1]

That is what I thought. Thanks for the clarification.

Scott