Culvert Headwater

[jaz2000]

if there are two consecutive culverts about 50 m apart how could the headwater of the second culvert affect the tailwater of the first. Does the backwater formed at the inlet of the second affect the flow regime of the first. another question about the headwater level to what distance it can extend transversally

 

[TerryScan]

All of your questions have the answer: "possibly"

One would need to analyze the entire scenario.

 

[francesca]

You need to calculate the headwater depth of the downstream pipe. It will extend as far as that contour, which, as you suspect, could affect your upstream pipe. Your tailwater depth of the upstream pipe will be equal to the headwater depth of the downstream pipe.

Really, though, this shouldn't be a problem, because if the pipes are 50m apart, you're not getting much additional flow to the second pipe and it'll only have to deal with the water coming out of the first. As long as the pipes are the same size, or the downstream one is bigger, and there's no significant change in flow, then you should be fine between pipes, but may have headwater issues upstream.

 

[dicksewerrat]

Look up the terms outlet control and inlet control in your text book. Use the formulae there and do the math.

Richard A. Cornelius, P.E.

http://WWW.amlinereast.com

 

[gbam]

Depending on the extent of "ponding" it may be advantageous to storage route through your culvert system. This may attenuate the flow and result in lower headwater for each culvert. You will have to make the determination whether the time to complete the routing is necessary. Otherwise, fransesca hit it on the head.

 

[ramzee]

try using EPA's SWMM to model the channel.
Shouldnt take much time but after you run it, you can see the water profile, sub-critical/super-critical changes etc.
Run the model with and without the second culvert, and see if the tail water depth for the first culvert changes.

Ramzee