Underground Limestone Rock With Pipe Outfall

[martin888888]

We have a situation at a mine site where we are designing a underground (roadway on top of it) limestone rock outfall (150'L x 20'W x 4'D) that will transfer water from a pond for treatment. At the end of the rock outfall we will have a culvert to discharge flows downstream. Easy enough to model the culvert, but is there a way to model the limestone channel and voids in rock available to transfer flows to the culvert?

 

[psmart]

The exact nature of the flow through the rock is going to be hard to predict with any accuracy. If you're confident that the culvert will be the effective flow control, then you could ignore the effects of the rock. In fact, if you have a "level pool" within the rock then you could even use the voids as part of the pond storage. On the other hand, if you expect a significant restriction (drop in WSE across the rock), then you may need to consider the rock as part of the outlet setup. If you have an expectation of the nature of the restriction you can probably simulate it with one of the standard outlets, but off-hand I'm not aware of any solid guidance for modeling those effects. Perhaps others on the forum have some specific recommendations...


Peter Smart
HydroCAD Software

http://www.hydrocad.net