# Please check my math. Lift station issue



## OpenSights (Mar 23, 2015)

I think I'm way off.

Situation is at an apartment two building complex, 48 units, that's on a lift station. The wye connection for the two pumps is cracked and is spraying sewage 8-10" high out of the cracks. We FINALLY heard back from the city and they have no information whatsoever. All we know is it appears that it isn't gravity from the pit to the city, and the manhole is approximately 130' away and 6" diameter.

The fittings are bolted flanges, above our capabilities, however the owner of the management company wants me to line up a plumber that does this sort of thing. I'd like to have as much info before I start calling around on Monday. I am out of my element, but common sense tells me when they cut the line, there's going to be a poop ton of water coming back into the pit. I'm trying to figure out the maximum possible gallons in this line.

Best I can come up with is:

cubic foot volume= Pi X diameter squared X length 

4900.896=3.1416X12X130

1 cubic foot = 7.48 US gallons 

4900.896X7.48= 36,658.7021 gallons worst case scenario? Am I missing something stupid obvious, or have some numbers wrong? No one really knows where it ties into the city main, we only know where the pit and the manhole are. 

Or am I just wasting my time and there's some sort of trick when having to replace a fitting in this type of system?

Edit: no shut offs.


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## OpenSights (Mar 23, 2015)

Make that 27,494.026 gallons. I used diameter when I needed to use the radius.


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## OpenSights (Mar 23, 2015)

Well it's been a few days since high school. 1,008 gallons.


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## tim666 (Mar 11, 2014)

Keep in mind that the radius is 3 inches or 0.25 feet when your calculating the volume

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## tim666 (Mar 11, 2014)

I got 190.83 gallons

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## OpenSights (Mar 23, 2015)

First mistake was using diameter, second was not changing inches to feet. Thought I finally had it right at 1008 gallons. I'll check it again.


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## OpenSights (Mar 23, 2015)

Yep, ~191 gallons. That sounds right now. Thanks!


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## wyrickmech (Mar 16, 2013)

Ok now there is some variables is it pumping into a gravity main or is it a pressurized main? This can be a big difference because if it is a pressurized main it should have a check just outside of the pit. Also it should have tracer wire along the discharge line. This could drastically change the amount of fluid you encounter. Without looking it up I know 6 in only holds around 1.5 per foot so if you have 130 feet tim666 would be correct.


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## justme (Jul 4, 2012)

PI X radius squared = square inches x 12" to convert to feet x footage of pipe divided by 231 to convert to gallons


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## tim666 (Mar 11, 2014)

Or as we say in Canada 722.37 litres


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## wyrickmech (Mar 16, 2013)

Tim666 is correct.


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