Lets say you used 8" pipe and have a 100' run, a 1' drop in the back will pull 777 Gallons per minute and a very safe velocity
2'=1130 GPM with velocity @ 7.21 Feet Per Second
3'=1407 GPM 9 FPS
4'=1643 GPM 10.5 FPS with a "V" 6' under ground that does nothing hope he glued it well and compacted underneath......personally at what ever grade is on outlet I would use the double 22.5 or double 45 fittings depending on the slope of the dam
A 6' drop is 2046 GPM with a velocity of 13 feet per second
Last edited by Huskerduck; 10/24/13 07:11 AM.
