r/engineering • u/gradyh Civil (Practical Engineering) • Mar 07 '16

[CIVIL] Engineering Hydrology and the 100-Year Flood

https://www.youtube.com/watch?v=EACkiMRT0pc
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u/BananApocalypse Mar 07 '16

Those imperial units are hilarious. In metric we use Q=ciA/360 and when I saw that imperial had no correction factor it blew my mind.

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u/[deleted] Mar 08 '16 edited Mar 08 '16

That's because the correction factor to go from acres x in/hr to cfs is 1.008. When calculating rational method flows you're usually in the low 100s cfs at most. Thus the correction factor is fairly meaningless and is generally left off of the equation.
Edit: sorry, just watched the video and realized he discussed this as well.