Does Water Drain Clockwise, Or Counterclockwise?

In graduate school, we learned that the Coriolis Force is much too weak on the distance scale of a sink to affect how water drains. Only over large distances is the Coriolis force large enough to affect fluid flow. Local friction effects and residual circulation determine whether water drains clockwise or counterclockwise from a sink, in either hemisphere.

Now that we were wise to this little Coriolis factoid, we made fun of people who believed otherwise.

Still, it would be nice to know.... The last time I shaved at Mt. Glorious, I paid attention to how the water drained, so as to know for sure.

The drain at the bottom of the sink was so large that the water didn't have a chance to drain either clockwise or counterclockwise - instead, the water drained straight down.