1D vs 2D vs 1D/2D Approach w/ Pumps and Lateral Structures

[DH]

Hello,

I am modelling a development area with 3 separate channels flowing to an estuary. I have called the channels West, Middle, and East. During a 100-yr event, water in Middle should rise enough to flow through an overflow culvert connected to East and to spill over into West. Water is discharged from West and East by pump stations while a sluice controls discharge from Middle.

Using Version 5.0.7, I have approached this as a 1D/2D problem, modelling the channels as separate 1D river reaches and the development zones as 2D areas connected to the reaches via lateral weirs.

However, I can’t successfully add a lateral culvert that connects Middle with a point between two XSs along East (it results in significant flow oscillations along Middle). Creating a new “connection reach” with an inline culvert doesn’t yield good results either (more flow through/over culvert than continues down Middle).

Does anyone have any suggestions regarding my approach? Also, what may be causing the instability when I add the lateral culvert?

Thank you,

DH

P.S. A 2D model would have been ideal, but it doesn’t seem possible to add pump stations to 2D areas in this version…

[Anonymous]

Honestly your approach with the lateral structure seems entirely appropriate. But there are so many potential solutions to your problem its hard to even begin writing about them without having the model in front of me to trouble shoot

[DH]

Thanks, Luis. I’m going to try modelling a 2D area with downstream reaches in order to get the pumps in… What I explained just wasn’t producing stable flows in the channels.

[Author]

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