EPAnet2, modeling connection to network 1

[hopeengr]

I just started using EPAnet2 software to model a small waterline project. I am connecting to an existing 12" municipal waterline with these criteria: static pressure 52psi, residual 46 psi, flow rate of 302 gpm and an elevation of 467 feet. How do I model this source with the software? (I am tying in with a 6" line wich reduces to a 2" line after 200'). TIA

 

[semo]

There is a lot more data needed on your system for the best analysis. You should analyze the system from the tanks/pumps to your point of connection.

If you have a point of low pressure currently in the existing system, your extension could cause it to drop even further. Without knowing the system or at least analyzing it, you won't be able to tell what impact you are having on it.

 

[hydrae]

Hopeengr

use a GPV control valve with uses an 'ID of head loss curve'

you can model the source as a reservoir feeding the control valve, (you may need a large short pipe between the two) the valve can follow any performance curve you define. Epa net will linearaly interpolate between the known control points.

Build a curve in the curve section and reference it from it the GPV, if all you have are the two points, use the H_Z equation to derive the rest of your posssible demands

Hydrae

 

[hopeengr]

Semo:
Thanks for your advice and I completely agree. It seems that I just can't round up enough information to perform an adequate analysis. You see, I am dealing with a rather small municipality and I can't track down the person holding the information! Actually, my crude calculations show the extension isn't adequate under even optimistic conditions of the existing system (just not enough water in the system).

Hydrae:
Thanks for the modeling tip. I will run it and see what I get.

 

[cvg]

Many cities won't allow 6 inch lines except for short runs, usually less than 500'. 2 inch lines are not recommended for anything other than a service connection in my opinion. 300 gpm through a 2 inch line would be impractical as the headloss would be in the neighborhood of 900' per 1000' of length.

 

[hopeengr]

cvg:

You just backed up my concerns on this project. What I didn't mention before is that I am only analyzing a system that was 'designed' by another engineer. The system is already in place and I have been attempting to justify what has been done. Being somewhat new to this (at least in the real world), I have been hesitant to question the work done by the previous engineer on the project as he has quite a bit more experience in this area than I do. I have been searching for a missing piece of this puzzle that would show that his design is adequate, but I haven't found it yet.

Thanks for supporting my sanity as I was beginning to wonder if I knew anything about water design.