SWMM EXTRAN - pump stations

People,

I need to correspond with someone who has run the SWMM EXTRAN model on a sanitary sewer system. I am using an interface to SWMM made by the CEDRA Corp. called AVSand. It has worked like a beauty in setting up and running the model. I am now working on a series of lift stations with float switches (modeled as off-line pumps) in this sewer model. I am getting it to run, but need to know if the way I have the pumps set up is correct. I'm not sure they are working as they should and I can't trust my output yet.

Main Questions:

I have the pumps pumping directly to a node and not to the pressure pipeline - is that the way it should be set up? If so how does this model handle pressure flow?

Another problem I am encountering with this setup is that my flows get higher with each pump station - higher than what was put in, so my total outflow is higher.

If you feel you can answer these questions - give me a buzz.

Thanks,
Thayne Clark
Bowen, Collins & Assoc.