Preventing Doomsday Act This bill directs the Department of Transportation to publish a report that explains (1) its contingency plan that details a specific plan of action in the case of a shutdown of a rail track in the North River Tunnel underneath the Hudson River and that addresses issues including ensuring commuters, tourists, and others will maintain the ability to travel between New Jersey and New York and throughout the region; and (2) its contingency plan detailing a specific plan of action to ensure minimal disruption to, and negative impact on, national security, the economy, public health, the environment, and property values.