Gutter Velocity

Question

I have a catch basin that direct bypass flows to gutter, which in turn discharge to catch basin. I've noticed that the gutter results show "N/A" for velocity. This leads me to believe that my flows are not being routed correctly. How can I correct this?

Jesse Dringoli · Answer

If you're using StormCAD or the GVF Rational solver in SewerGEMS or CivilStorm, the velocity result is not applicable for a gutter. Bypass flow from an upstream catchbasin will pass directly to the element at the downstream end of the gutter. 
 
Keeping in mind what you see in the User Notifications and the convergence results in the Calculation Summary, the gutter results should otherwise by routed correctly. If you notice a problem , it would help to post your model files along with steps to observe the issue. You can also search through the Help and the Hydraulics and Hydrology Wiki to find other information related to assumptions used when routing rational flows (such as how the controlling time is determined to calculate rational flow in conduits, bypass flow, carryover flow, etc at each point in the network).