Do Toilets Flush in the Opposite Direction Depending on the Hemisphere you are in?

The Coriolis effect

            It is commonly known that while watching a sink drain or a toilet flush in the Northern Hemisphere the water will drain in a counter-clockwise direction, and in the Southern Hemisphere the water will drain in a clockwise direction.  The real question is, is this fact or fiction?  What leads us to believe this is true or untrue? “The origin of this myth comes from applying a scientific principle to a situation to where it does not fit.  The Coriolis deflection causes cyclonic systems to rotate counter-clockwise in the Northern Hemisphere and clock wise in the Southern Hemisphere.  It was inevitable that someone would suggest (without checking) that a sink should drain in a similar manner,” according to Snopes.com. 

            A survey was taking by 17 9th grade students on this myth. The students were not given any information on this myth.  All they had was common knowledge to answer the statement, “Toilets and sinks drain in the opposite direction in the Southern Hemisphere.”  Each student was given the option of answering “Fact”, “Fiction”, or “Unsure”.  The gender and age of the student was asked as well.

9th Grade Student Survey on their beliefs of Toilets and Sinks draining in the Opposite direction in the Southern Hemisphere.

Age	Gender	Fact	Fiction	Unsure	Total	Average
14	Girl	7	0	0	7	7
14	Boy	6	0	0	6	6
15	Girl	1	0	0	1	1
15	Boy	2	1	0	3	1

The survey showed that on average, 94% of the students thought it was true.  47% of the students who thought it was true were female.  6% of the students who thought it was untrue were male.  76% of the students asked were the age of 14, while the other 24% of the students were the age of 15.

The truth is that this myth is false! This myth that seemed to be widely known as true is fiction!  People believe that this is true because of the Coriolis force, which is an effect that imparts a twist to largish events happening away from the equator.  The Coriolis force causes water to turn counter-clockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere.  The Coriolis effect happens over long measurable periods of time and over huge distances.  Neither of which can be applied in your bathroom.  The reason a toilet and sink drain the way they do is because of how the water is directed into them or pulled from them.  The way the water is entered into the toilet is the same way the water is going to exit the toilet.  The widespread myth has been spread through television shows and in textbooks.  Numerous hucksters who have set up fixed demonstrations around the equator to amuse the gullible tourists have also publicized it.  Recently discovered in a published introductory meteorology textbook includes this misbelief as one of the subjects students commonly ask about.  The answer is, “The origin of this myth comes from applying a scientific principle to a situation to where it does not fit.  The Coriolis deflection causes cyclonic systems to rotate counter-clockwise in the Northern Hemisphere and clock wise in the Southern Hemisphere.  It was inevitable that someone would suggest (without checking) that a sink should drain in a similar manner.”

Citations:

http://www.snopes.com/science/coriolis.asp

http://www.travbuddy.com/travel-blogs/6181/Coriolis-Effect-toilets-flush-3

http://www.squidoo.com/toiletflushdirection#module11508692