Assuming that 18 inches refers to the diameter, it will hold 55036 Imperial gallons.
In a pipe with diameter 8 ft, there will be just over 376 US gallons per foot.
There need not be any water in the pipe! The volume of the pipe is 1044 Imperial gallons
U tell me
10.4448, assuming 16" inside diameter. 16" outside diameter would be slightly less.
A 12 inch diameter round pipe will hold 4.89 UK gallons or 5.88 US gallons per foot.
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Over 9,000.
One foot of 3 inch pipe will hold approximately 0.625 gallons of water.
15.29 Gals
The volume is 31.809 cubic feet.
A 4-ft diameter pipe holds approx 78.3 US gallons.
Assuming that 18 inches refers to the diameter, it will hold 55036 Imperial gallons.
A four-foot diameter pipe that is five feet long has a volume of 470 gallons.
About 11.3 feet of 3" pipe can hold 5 gallons of water.
This pipe will hold 23,500.7 gallons of water.
For a 3 foot diameter pipe, 52.9 US gallons per foot of length.