Ponds in Series
Ponds in Series
(OP)
A coworker has modeled a series of 3 ponds separated by 2 roads and 2 sets of large box culverts(with a weir) to equalize the 2 upstream ponds. The final outfall is a small stone box culvert under a railroad track. When I take out the road crossings and model this as one large pond with several subcatchments I get a 100year elevation 2.5' higher than he does.
Since the storm elevations back up into the upstream ponds; his theory was to add the upper ponds elev-areas to the lower ponds to make it more realistic.
We are in debate as to whether ponds in series automatically account for other ponds volumes as the elevation rises into one another or whether his method is accurate, I feel like he is double dipping on storage and getting false results. We are using the Dyn-Stor-Ind Method.
Please help
Since the storm elevations back up into the upstream ponds; his theory was to add the upper ponds elev-areas to the lower ponds to make it more realistic.
We are in debate as to whether ponds in series automatically account for other ponds volumes as the elevation rises into one another or whether his method is accurate, I feel like he is double dipping on storage and getting false results. We are using the Dyn-Stor-Ind Method.
Please help





RE: Ponds in Series
http://www.hydrocad.net/dsi.htm
RE: Ponds in Series
RE: Ponds in Series
RE: Ponds in Series
RE: Ponds in Series
Just use three ponds, each routed directly to the next: A->B->C
Enter the available storage within each pond. This is the volume that is directly controlled by the pond's outlet device(s). Don't include the volume for any other nodes, upstream or downstream. These volumes are accounted for separately in their respective nodes, and should not be double-counted.
Peter Smart
HydroCAD Software
www.hydrocad.net
RE: Ponds in Series
RE: Ponds in Series
Peter Smart
HydroCAD Software
www.hydrocad.net
RE: Ponds in Series
Is it possible to get reversing flow when/if the pond elevation downstream is higher than the upstream pond? If yes, you may need to use additional software to evaluate that scenario; Interconnected Pond Routing (ICPR) or similar. I do not use HydroCAD so maybe Peter can answer if HydroCAD handles that scenario.
RE: Ponds in Series
Hydrology, Drainage Analysis, Flood Studies, and Complex Stormwater Litigation for Atlanta and the South East - http://www.campbellcivil.com
RE: Ponds in Series
RE: Ponds in Series
To be clear: Tailwater means that the discharge is reduced by the downstream water surface elevation, but water is always flowing in the same direction from A to B. Reversing flows means that the flow actually changes direction, flowing first from A to B, and then from B to A.
For details see www.hydrocad.net/tailwater.htm
Masterbase: When you say the elevations were 2' higher with SimRoute, I'm guessing there were warning messages in one of the models? The warnings are intended to identify modeling issues (such as oscillations) that may compromise the results. Please review and resolve any warning messages before you draw any conclusions from the results.
Peter Smart
HydroCAD Software
www.hydrocad.net