This fellow posts an interesting pager newsletter.
Brad Dye
Of particular interest and appropriate to this thread is the Issue #182 : Sept 30 edition. It seems that plain old two-way pagers continued to function quite well during the NOLA event. The article in question is about 1/2 way through that newsletter. I would also encourage reading some of the other issues before & after that date.

Best Regards,

Sandpine