Understanding Catchbasin Known/Additional/External flows

Product(s): SewerGEMS, CivilStorm, StormCAD
Version(s): 08.11.XX.XX and 10.00.XX.XX
Area: Modeling


Using the GVF-Rational (StormCAD) solver, what are the different types of inflows that a user can apply at a catch basin and where specifically does the flow enter? (subsurface or inlet approach)


Catchment Rational Flow: Rational flows that approach the inlet at the surface.

External CA/Tc Flow: Rational flow that enters subsurface.

Additional Subsurface Flow: Additional flow entering subsurface.

Additional Carryover Flow: Additional flow entering above the inlet (can be bypass).

Known Flow: Supersedes all upstream flows at this point in the system and enters subsurface.

Note: For flows that enter subsurface, they are not subjected to the inlet-specific result field such as Flow (Captured) so these fields may show zero flow. (because those flows do not approach the inlet.

See Also

Understanding Known Flows

Understanding Flow (Additional Subsurface) and Flow (Additional Carryover)

Entering catchment data directly to a catch basin