How to Calculate Water Flow In Pipes
Conserving water is an economical idea--whether your motivation is to save water or decrease the size of your monthly utility bill. By following a basic procedure, you quickly can calculate the amount of water that flows through your pipes in gallons per minute. Does this Spark an idea?
Things You'll Need
- Plastic bucket
- Four- to eight-cup measuring cup
- Black marker
- Stop watch or a watch with a second hand
Instructions
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1
A gallon of water contains 16 cups of water. Two cups are equal to one pt. and eight pts. pints make a gallon. Fill the plastic bucket with water using the measuring cup. The bucket should contain a full 16 cups.
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2
Mark the outside of the plastic bucket with the black marker at the level water line to indicate the one-gallon watermark. You might want to mark the outside of the bucket in several places for an accurate measurement.
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3
Empty the bucket into any drain and take the bucket to the spigot or pipe for the first flow you want to measure. Place the bucket under the pipe opening and have the watch ready to record the amount of time it takes the water to fill to the one-gallon mark.
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4
Open the water valve fully and begin to record the time. You must have the valve or faucet fully open to accurately calculate the flow rate.
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5
Perform the calculation for the flow rate of the following example. The one-gallon mark was reached in 20 seconds. Because all flow rates are expressed in gallons per minute (gpm), you will need to find how many gallons flowed in the 20 seconds. If you divide 60 seconds (the number of seconds in one minute) by 20 seconds, the result is three. This will equate to the water flowing at a rate of three gallons per minute. If the bucket was filled in 10 seconds, then the rate would be six gpm.
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6
Calculate a lower flow rate, such as the bucket took 120 seconds to fill to the one-gallon mark. Divide 60 seconds by 120 seconds and the result would be 0.5. This would equal a flow rate of 0.5 gpm, or half a gallon of water per minute of flow.
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