Do Toilets Flush Backwards in the Southern Hemisphere?

Common Myth of Backwards Flushing

There is nothing in scientific research to indicate that toilets flush backwards in the Southern Hemisphere, though myths abound to the contrary. It is a popular misconception that due to the Coriolis effect, which is the curved path of moving objects in relation to Earth’s surface, water movement is reversed between each hemisphere. In fact, the Coriolis effect would impact conditions only on a much larger scale, such as in major weather patterns.


Coriolis, Hurricanes, and Toilets

Hurricanes are affected by the Coriolis and, indeed, these atmospheric conditions do spin differently in each hemisphere. However, this effect is on a much larger scale and does not influence the water flow in toilets or sinks. Hurricanes cover a great area and continue for a span of days. The flush of a toilet, on the other hand, is in a very small space and occurs in a very short span of time. The water flow is influenced instead by the design of the water fixture and the way that water enters the fixture. Water generally enters a toilet in a swirling motion and, thus, the flow follows the direction of the swirl. Applying the Coriolis effect principle to the water flow in toilet flushing is not logical. Weather patterns may vary, but water simply flows as the fixture was designed.



“atmosphere (gaseous envelope) : Convection, circulation, and deflection of air — Britannica Online Encyclopedia.” Britannica Online Encyclopedia. N.p., n.d. Web. 28 Aug. 2012. <http://www.britannica.com/EBchecked/topic/41364/atmosphere/261453/Convection-circulation-and-deflection-of-air#ref952920>.
“Coriolis force (physics) — Britannica Online Encyclopedia.” Britannica Online Encyclopedia. N.p., n.d. Web. 28 Aug. 2012. <http://www.britannica.com/EBchecked/topic/137646/Coriolis-force>.


“Does water go down the drain counterclockwise in the northern hemisphereand clockwise in the southern hemisphere? (Everyday Mysteries: Fun Science Factsfromthe Library of Congress).” Library of Congress Home. N.p., n.d. Web. 28 Aug. 2012. http://www.loc.gov/rr/scitech/mysteries/coriolis.html


Fun Facts