I've seen a few articles over the past couple days that raise the question of a link between groundwater depletion and the recent quake in Napa Valley, and it's a tempting connection to make.
It ties in with concerns about fracking. There actually is solid evidence to indicate that the drought has caused crustal deformation and uplifting. Of course, there's just something about feeling the earth move beneath you, that makes you look for a culprit.
If thinking the drought caused the earthquake encourages people to restrict their water usage, it might be just as well to let them continue thinking so. It's important to remember however, that the specific causes of an earthquake are essentially impossible to state categorically, and that California has a rather lengthy history of them.
It will likely take scientists many months if not longer to come up with the cause of the 6.0 earthquake, which was the largest for the Bay Area since 1989 during the World Series.
The much feared and revered San Andreas fault lines have been looming over Northern Californians since "The Great Quake" of 1906 destroyed San Francisco, but this most recent fault of the series that cover over 20 miles of the Napa Valley, could just be the work of the
Franklin Fault. The Franklin is a crack in the Earth that has been dormant for 1.6 million years.
The stress to major faults from the loss of ground and surface water over the past 18 months is the equivalent to the amount of stress every week due to plate movement. Furthermore, the changes in climate have no bearing on plate tetonics according to scientific studies.
If blaming the drought on an increased likelihood of major earthquakes would prove a positive deterrent to water waste from over consumption, then subscribing to such a theory, while probably faulty, would still be a good use of time and energy.
However, unfortunately there are probably far more people-- who by grabbing onto to such beliefs-- seek to drag the drought into the Napa Valley earthquake to avoid taking ownership of the need for water conservation. Might Mother Nature, who holds the keys to the "Big One." be an equal co-conspirator in our water crisis? That's a faulty logic and a tricky diversion from our human culpability for our water crisis.
Our cause and effect for our crippling drought are much more cut and dry than how and when the next tremblor is going to strike.