Is it possible tho determine the pollutant levels in sewergems using a sewer system that has a mixture of gravity and pressure mains? I'm trying to determine how long it takes for flow to travel through a sewer system to the outfall and my initial thoughts was to use the pollutant/pollutographs
Yes you can use the SWMM Solver in CivilStorm or SewerGEMS to model transport of pollutants in your sewerage system,
Here is a reference article which can help you on that;
Prediction of quality characteristics of sewers
Hope this helps.
Bentley Technical Support
I'm still not seeing pollutant results downstream. I'm currently testing this by using a simple model which has the following components:
- wet well with pump and virtual pipes
- Pressure pipe/pressure junctions
- manhole/conduit to outfall
My test pollutant discharges into he upstream manhole. The model results shoe the pollutant results only goes the wet well. There are no pollutant results recorded in the pumps or pressure mains. Downstream in the manhole/ conduit there are no pollutant results.
Sewergems is only allowing pollutant results to be displayed from the gravity nodes, not pressure nodes.
This could be due to the virtual links connected to the pump upstream and downstream.
You can simulate the use of a wet-well and pump by placing two pressure nodes separately (no connection between them) with outflow and inflow. See the below article for more details;
Estimating a pump curve for a model
Hope this helps.
Do you have a worked example using sewergems with the SWMM engine? Will the pollutant still come through if there is no connectivity?
I have prepared a sample model for the case as described above. I will share the model files with you.
However, the pollutant loading has to be done when there is no connectivity (to simulate pumped flow as shown in the link above) at the downstream manhole again.
SWMM Pollutograph Example
I have used arbitrary concentrations. You can check for the loading as per your case.
let me know if this helps.
Answer Verified By: Sushma Choure