[jennifer russell]

Pardon my ignorance, what do you mean by modeling the canal and gate with a constant head?
One of the main goals of this project (besides rehabbing the deteriorating dam structure) is to reduce the amount of effort that goes into opening and closing the headgate slide gates. For almost the entire irrigation season, our client is limited to what they can take from the river. The river flows vary greatly hour to hour, day to day, week to week, and so they have to adjust the opening of the gates. This requires a significant amount of time. They are considering a SCADA system to take care of it, but costs may be prohibitive and even then, we would want to try to minimize the amount of operation (= electricity to run the gates). At the very least, I need to be able to show how often they will need to adjust the gates given average river flows and the constant flow they are allowed (every drop of which they very much need).

[jennifer russell]

I’ve done this model two ways: First I did the River to Canal lateral structure without any gates – just culverts. Below are screen shots of geometry and results tables.

The second is with gates on the lateral structure and an inline structure with culvert. Below are screen shots of geometry and results. It is confusing that the Canal inline structure doesn’t show any flow in the culverts but there is flow in the Canal downstream of the inline structure.

I’m really beginning to hate HEC-RAS!
I *REALLY* appreciate your looking at this!

[jennifer russell]

Inline Structure in River:

Lateral Structure in River discharging to Canal:

Inline Structure in Canal:

Canal Profile:

[jennifer russell]

Oops – forgot to say the velocities in the culverts in the headgate will be in the neighborhood of 3.4ft/sec when flowing full.
The slope on the canal is 0.25%.

[jennifer russell]

What things should I look for regarding flow limitations? This is for steady flow.
As for doing a 2D model, we didn’t have the budget to do the surveying and modeling at this stage. We are doing preliminary design – will be recommending doing 2D for final (new budget – doing prelim design so they know how much to apply for next phase funding).
I think I will post screen shots of the inline and lateral structure model info so others can take a look.
Thanks!

[jennifer russell]

This is in middle-of-nowhere Wyoming (which is a little bit redundant). We don’t have alot of the extra resources other places have.
I’m mostly concerned with the interaction with the inline and lateral structures in the model. Currently I just have the headgate as uncontrolled culverts in the lateral structure.
Any advice with adding in gates?

[jennifer russell]

[jennifer russell]

Ahh. Apparently that only shows up if your are registered – easy enough to do now.
Thanks!!

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