I have a newly impounded and filled 16 acre lake with a 54" diameter riser pipe spillway. I would like to raise the height about 6" to put the water up on my dock without getting high enough to kill an oak on the bank. The pipe is corrugated and I have already raised it 18 inches due to contractor error in setting it. I used a pipe coupler and a rubber gasket but this was expensive. The pipe has a 36" antivortex baffle bolted to 4 legs on top which gives me a sturdy support. If the design fails and I lose the 6 inches of water, no big deal. Any ideas?

How about blocking the bottom 6" of the pipe inlet, preferably with something that would be removable if needed? The loss of a 6" tangent of cross-sectional area would be a pretty small % of the total inlet area; IF you were expecting to have a major rain event (i.e. hurricane) you could yank the 6" block out to regain maximum drain flow.

P.S. Welcome to the forum, Dr. McCoy!

The 54" riser pipe is vertical and drains into a horizontal pipe. Thanks for the reply though.

Hi Bones,

Could you swap a 24" section of pipe for the 18" section you used previously, and still use the coupler and gasket?



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He's Dead Jim

Actually the section is 24" with 6" of it fastened to the pipe. I probably will just bite the bullet and buy another section to get the level I want.

Biting the bullet would be the best and SAFEST solution. Any make-shift extentsion could fail and get sucked into the pipe potentially causing a severe blockage OR let such a huge, sudden outflow occur that could do some serious damage at the output area. It could even be intense enough to damage the riser section. Any of these repairs could be a lot more costly or dangerous than the cost of another pipe.

Ahhh! Words of wisdom.

Thanks Rainman