Your better off spreading the risk all over the place. If all the places go down at the same time, I think you have bigger problems. Besides, I think most of the large institutions have accounted for this already.

I think the real risk here is the loss of life (bus factor).

Here are some useful maps:

http://www.hazardscaucus.org/presidentialdisasters65-98.JPG

http://www.datafoundry.com/wp-content/uploads/2011/04/natura...