Here's a few factual timelines if humans are no longer able to operate the systems that provide power. One is from the History Channel 'Life After People" http://www.amazon.com/Life-After-People-History-Channel/product-rev... and the other is a zombie scenario from a site called "The Straight Dope" http://www.straightdope.com/columns/read/2165/when-the-zombies-take... Didn't know where to post this, but it's quite interesting to see how fast the cities would go dark. "Life After People" even had tigers running around the White House just like " I Am Legend" And go figure the cockroaches will survive and actually thrive when we are gone.
So if you go into the cities several years after WWZ you won't even recognize it. If you can order a used copy of "Life After People" it's worth it.It should start again with 9 new episodes this month.
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