Creating a Riprap Check Dam

[GRunyon11]

I have a project with a simple detention pond. The outlet structure is a 12" pipe with a 6" orifice routed to the pipe, and then a 30 inch diameter inlet that routes to the pipe as well (the invert of the pipe and orifice is 840.29, and the invert of the inlet is 844.37). The problem is that I have to model a riprap check dam in order to meet stormwater quality measures. I was going to set the top of the weir at an elevation of 842. Is there any way to make Hydrocad analyze the flow of water over the weir before it enters the pipe (perform all of this in one pond), or do I need to set up 2 ponds, with the first one having the weir as the primary outlet, and then the second pond with the outlet configuration and the storage beginning at elevation 842?

Thanks.

 

[psmart]

Although I'm not 100% clear about your outlet configuration, you can put the weir in the same pond by routing the weir flow to the 6" orifice. This will require all flow to the orifice to pass over the weir first.

For details on device routing please see

http://www.hydrocad.net/pond1.htm

Peter Smart
HydroCAD Software

http://www.hydrocad.net

 

[beej67]

What municipality are you in? I've heard lots of them asking for check dams in front of outlet control structures, but I've never heard of one wanting them incorporated into a hydrologic model.



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