He's off, but not by as much as you'd think, and including water would probably put that scale in better perspective.
If we assume that a "typical intake" of water is one 8oz (~.25 liter) glass, and the LD50 of water is about 6 liters for an average (165lb) person, then we're looking at a ratio of approximately 1:25. That would make the bar for "water" about twice as big as the one for "meth" on this chart.
Ignoring that this is a stupid way to measure danger, their ratio on Alcohol is way too low (though I see elsewhere that they may be talking about injecting alcohol, which completely invalidates the point of the findings since that's not how we typically consume it).
In their own paper they say that the range of low to average usage is 1-4 drinks a day by typical users, then give it a ratio of "1:1.5" between typical usage and fatal dosage. How the heck does that work out? That makes the "lethal" dosage from 1.5-6 drinks a day, which seems way too low. To get to the level of drunk where you risk any sort of death drug-related death (suffocation by vomiting and choking if you happened to fall asleep) you'd have to get to a BAC of 0.2% which is about 8 drinks in one hour for our illustrative 165lb male. ( http://en.wikipedia.org/wiki/S... )
Even if their average dose of "X drinks a day" was actually "X drinks in an hour", the lowest plausible ratio is between 1:2 and 1:4 depending on what you consider "average" daily drinking. To get anywhere near LD50 I'd expect you need to get closer to 1:7 ( ~0.3%+ BAC ) which would be where you start to add unconsciousness and respiratory depression as effects. That would put it between Cocaine and Tobacco, closer to the latter, on their chart, which seems about right.
tl;dr Article should be named "Scientists find new, bad way to measure 'danger' which shows alcohol 10x more dangerous than meth, meth nearly twice as dangerous as water".