The Department Of Homeland Security has a current solicitation out which looks to make heavy, priority use of the VERIZON network during National Emergencies, Disasters, Pandemics, or any other situation where the government demands priority use rights of the telecommunications infrastructure. Of course, that likely means you can expect your Verizon phone to be a paper weight when you might really need it.
"During the September 11, 2001terrorist attack, general public calls experienced a 15% call completion rate in certain areas, while GETS calls completed at above 90% in the same locales."The solicitation and associated word document is a must read for anyone counting on their phone as their primary disaster lifeline.
Sources:Department of Homeland Security (DHS)/Government Emergency Telecommunications Service (GETS)Solicitation Number: HC1013-04-C-5001
Redacted J&A for Verizon Government Emergency Telecommunications Service (GETS) Next Generation Network (NGN) Voice Over Internet Protocol (VoIP) Core Network Deployment