| Product(s): | StormCAD, CivilStorm, SewerGEMS | ||
| Version(s): | 08.11.XX.XX and Later | ||
| Area: | Modeling |
After computing a model, one of the following messages is generated:
"There is no gutter leaving this 'On Grade' catch basin. Bypassed flow is directed to the subnetwork outfall."
"The associated 'On Grade' inlet does not have a bypass gutter. The bypass flow will exit the system."
What does this mean and how can I resolve it?
This messages is warning you that the catchbasin's inlet is set to be on-grade, but you have not defined a downstream gutter link element. Gutters are needed so that the program knows how to direct any bypass flow (not captured by the inlet) to the next downstream inlet.
For example if the bypass flow from an upstream catchbasin travels down a gutter which approaches the next downstream catchbasin, then you will need to draw a gutter link between them. If the catchbasin is actually in-sag and captures all the approach flow, then set the inlet location to In-sag instead of On-grade.
Note: When using the dynamic solvers such as Implicit and Explicit SWMM Solvers the overflow volume can be found under the Hydraulic Reviewer found under the Analysis Tab. Just select the node element (catch-basin, manhole) and run to see the overflow volume. See here to know how overflow volumes are handled by the dynamic solvers.
Note that in the event that this occurs and there is bypass flow with one of the dynamic solvers in SewerGEMS or CivilStorm, the catchbasin will present the bypass flow in the "Flow (Overflow)" field and will be accounted for in the overflow volume part of the mass balance. This will also flag the "Is overflowing?" as "true", even if the subsurface network's HGL has not reached the rim elevation.
Overflow reported at catchbasin even though HGL below rim elevation
| Original Author: | Scott Kampa |