bridges that can completely collapse when just one part gives way. here's a look at some of the countries major bridges that need repair. a portion of the i-10 in los angeles. the i-25 in denver. and bridges in new jersey, nevada and virginia. in 2011 more than 66,000 american bridges were labeled structurally deficient. joining me now via skype from connecticut, steven flynn, the author of the book "the edge of disaster, rebuilding a resilient nation." are these bridges dangerous to travel on right now? what's going on? >> well, they're not dangerous under normal circumstances here, but they're a warning sign. should be a big blinking red light that we as a country have inherited a bunch of infrastructure and we haven't been keeping it up very well, never mind upgrading it for the kinds of needs we have going forward. >> you believe that ignoring these huge infrastructure