I have an 8" Sch 40 PVC pipe the NRCS calculated a "peak outflow" of 4.72 cfs (2,118 GPM) at an effective height of 19 feet and 113 foot long pipe. I assumed that is in siphon mode but not sure.

This reminds me I need to haul in more broken concrete to dump in the discharge area before it eats out a big hole this spring.


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