How is water pressure expressed in relation to head in a pumping system?

Water pressure in a pumping system is commonly expressed in feet because it relates directly to the height (or head) of the water column that can be supported by that pressure. This measurement is crucial for understanding how high water can be pumped and is a fundamental aspect of hydraulic engineering.

When water pressure is described in terms of head, it indicates the vertical distance the water can be lifted. For example, if a pump generates a pressure sufficient to lift water 50 feet, that translates to a hydraulic head of 50 feet. This concept helps water treatment operators evaluate pump performance and system efficiency since the height (measured in feet) provides a clear picture of the potential energy of the water.

While other units such as psi (pounds per square inch) can also measure pressure, they do not directly correlate to how high water can be lifted. Likewise, measurements in gallons per minute or liters pertain to flow rates, not pressure head. Therefore, expressing water pressure in feet provides a practical understanding of its effect on the pumping system's ability to move water.