New York City's video on how to survive a nuclear attack.

[Anomalocaris]

I recall reading the atomic bombing of Hiroshima and Nagasaki, and postwar tests, show a person inside a sturdy building can survive at much wless than half the distance from the hypocenter as the minimum distance a person in the open has any chance of surviving the blast.     There was a case of a Japanese woman inside a reinforced concrete bank building lobby who survived with remarkably little physical injury something like 300 feet from the hypocenter.     

It is actually not easy to get a lot of people into the sewers on short notice.    One also wonders whether the sewers provide survival advantage in the case of a ground blast, since the sewer tunnels are usually quite close to the ground, so a ground blast fireball would seem likely to breach the sewer tunnels, providing potential for sewer tunnels to confine and channel the blast, causing the blast to remain lethal in the     sewer system much further away than in the open air, where the blast is easily dissipated and its intensity attenuates by a factor equal to square of the distance form the blast.    The amount of liquid in the sewer would also seem to bear in the survival shelter value of the sewers.   If a ground blast breaches the sewer system with a high liquid load, would the blast cause a mini tsunami and drown or wash away those seeking shelter in it? 

Btw, if it really is us against the rats in the sewer, i don’t think in the end we will win.    Both humans and rats are smart, but rats are less conceited and breeds more.