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How does Archimedes' screw lift water for irrigation?

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A diagram displays six types of simple machines with labeled illustrations: inclined plane, wedge, screw, lever, wheel and axle, and pulley, each shown with real-world examples like ramps, axes, screws, seesaws, door handles, and pulleys lifting objects. — simple machine Six simple machines for transforming energy into work.

The Archimedes screw is a device used to lift water, typically consisting of a circular pipe that encloses a helix or a helical tube wound around a shaft.12

To function, the device is inclined at an angle of approximately 45 degrees to the horizontal, with its lower end submerged in the water source. As the screw rotates, it traps water within the helical chambers. Because of the device's orientation and the continuous rotation of the helix, the water is effectively "pushed" or lifted upward through the pipe until it reaches the desired height for irrigation or other purposes.1

While the invention is traditionally attributed to the ancient Greek scientist Archimedes, historical evidence suggests that similar devices were used for irrigation in Egypt prior to his time. In modern applications, such as wastewater treatment, these pumps often use open inclined troughs, which allow for the efficient movement of water and debris without clogging.31