How long will it take to pump the water out of the basement?

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Question from Shiva, a student:

I need to pump water out of a flooded basement, using two 50 (gpm) pumps. The basement has the dimensions shown and is flooded to a depth of 16 inches. How long will it take to pump the water out of the basement?

The diagram has 40feet, 50feet, 24feet, 22feet.

Shiva,

Can you send the diagram? I can't answer your question without knowing the shape of the basement.

Harley

Hi

Here is the Diagram Attachment

Thank You,

Shiva

basement

Shiva,

You can divide your basement into two rectangle, A and B, one 40 ft by 28 feet and the other 16 feet by 22 ft.

basement

The watre is 16 inches deep so and you can use our volume calculator to calculate the amount of water in the basement.

A: 40 ft by 28 ft by 16 inches gives 11171 U.S. gallons
B: 16 ft by 22 ft by 16 inches gives 3510.9 U.S. gallons

For a total of 14681.9 gallons. At 50 gallons per minute it will take 294 minutes which is about 5 hours and hence with 2 pumps about 2.5 hours.

I hope this helps,
Harley

Shiva,

Steve looked at my response and suggested that I mention that the last couple of inches will probably not pump out at full speed because of the water shape/air gulping.

Harley

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