I need help in modeling a storm sewer system in sewergems

Hello Jefry, 

Do you any diversions in the model? Which solver are you using ( Analysis > Options > Active numerical solver) ?

If not do you have any loops in the model with GVF Convex or Rational solver? Check if you have outfall in the model, if it is pressurized system then there should be wet well to store the flow. 

If you have placed the network elements correctly following the guide and outfall or wet well is there in place in model, then this could be due to diversions or looped pipes in the model.

Could you please upload model files for our review? 

Also please check if there is need of diversions in the model, using following article. 

Modeling a flow split (diversion) with the SewerCAD or StormCAD numerical solver 

Hi Sushma,
I am using GVF-Convex, the model I am using is somewhat complex and well, I have several falls to store the flow.
I have followed the guides of other forums and I estimate that I have a loop in the system and I have not been able to solve it.
The information is uploaded for your review.
In some points of the system I have applied the deviations, but in the latter this solution does not apply, sorry my English is not entirely excellent.
Greetings from Colombia.

JEFRY_NOVOA_ACERO_COLOMBIA.rar

Hello Jefry,

I checked your model and I can see that the branch from catchbasin S8 onwards is showing the error "gravity sub network does not have downstream wet well or outfall". This branch ends in outfall D2. But right before the outfall the conduit P212A-D2 is a diversion link which is causing the program to not recognize this as a gravity sub network. As my colleague Sushma pointed out in her response, check for elements which are diversion links. Here the diversion link P212A-D2 doesn't make sense as there is no branching before the outfall. Did you setup the diversion link as a means to control the flow towards the outfall?

If that is the case then you can use conduit start / stop structures to do so.

Hello Jefry,

I checked your model and I can see that the branch from catchbasin S8 onwards is showing the error "gravity sub network does not have downstream wet well or outfall". This branch ends in outfall D2. But right before the outfall the conduit P212A-D2 is a diversion link which is causing the program to not recognize this as a gravity sub network. As my colleague Sushma pointed out in her response, check for elements which are diversion links. Here the diversion link P212A-D2 doesn't make sense as there is no branching before the outfall. Did you setup the diversion link as a means to control the flow towards the outfall?

If that is the case then you can use conduit start / stop structures to do so.