Flow Measurement: Which device is commonly used to measure flow in irrigation supply lines?

• A. Thermometer
• B. Flow meter
• C. Barometer
• D. Altimeter

Answer: (B)

Measuring how much water is moving through irrigation supply lines is done with a flow meter. It provides the flow rate (like gallons per minute or liters per second) and can also track total volume over a run, which is essential for verifying system performance, calibrating emitters, and detecting leaks or blockages. In practice, you’ll place an inline or insertion flow meter in the main or branch line to monitor how the system is delivering water to the zones.

The other tools measure different things: a thermometer watches water or air temperature, a barometer measures atmospheric pressure, and an altimeter tracks elevation. None of these give the actual flow information needed for irrigation performance, so they don’t fit for measuring flow in supply lines.