Good evening from tampa. The countdown is on. Just a few hours, republican presidential candidate mitt romney will take stage and try to give the speech of his lifetime to tens of millions of people.... See More
Good evening from tampa. The countdown is on. Just a few hours, republican presidential candidate mitt romney will take stage and try to give the speech of his lifetime to tens of millions of people. But tonight, once again, first, we want to take you straight to the gulf coast because isaac is now saturating louisiana and mississippi. It is a day filled with high stakes evacuations and heroism. And tonight there is real concern that a dam could collapse just 80 miles outside new orleans. Abc's extreme weather team is out once again across the storm zone. Matt gutman starts us off in new orleans. Reporter: These are the desperate scenes playing out in louisiana tonight. Look as these faces, young old, yet relieved as the rescuers arrive. So many on the move as the waters rise. New anxiety tonight. Tens of thousands of people told to evacuate when a dam threatened to evacuate. Many were given just 90 minutes to gather all that was dear to them and flee. Pictures -- baby pictures of me and my siblings, my children, my sister's children. Reporter: How stressful is this? You have very little time. Very stressful. Reporter: The flooding and rain have simply swallowed up whole communities -- this deer barely able to keep its antlers above the water. In laplace, louisiana, more than 3,100 residents evacuated in a helter-skelter rescue by helicopter and boat. We set out with the alpha team of the louisiana wildlife and fisheries. We'll work our way back. Reporter: We found an eerie scene. Even rescuers were shocked. Nobody expected this. the worst-case scenario, but the people didn't expect it. Reporter: This woman searching for her father -- anyone there? Reporter: While most of her neighbors had been ferried to SAFETY, anna McLung was still trying to pack up her life. My house is ruined. Reporter: Shy boarded our boat and we brought her to safety. While the fortress of levees rebuilt around new orleans in the wake of hurrickatrina kept the city safe, some of the smaller surrounding communities were swamped as their own local levees failed to protect them. I'm standing on one of the levees that protected new orleans during the storm. It's 25 feet high on either side. Those communities did not have the benefit of that type of protection. Tonight, however, there are thousands of first responders shepherding them to safety. While this storm may have passed, this crisis is not over. All right, matt, from the rising floods where you are on the ground, we wanted to see the whole picture of the water from the air. Abc's bill weir rode along with the coast guard. Reporter: It you happen to be trapped by high water, coast guard pilots like caitlin mitchell-wurster could be your best friend in the world. Her office is a bright orange dolphin helicopter and her busy season starts the moment a hurricane leaves town. After a night of plucking the helpless out of la place, she was kind enough to give us a tour of the aftermath. On good days, the gulf of mexico is their backyard. On bad days like this, it is the whole yard and the living room. We crossed over slidell, where they build mansions on stilts for a reason and plaquemines parish, where more humble abodes are drowning thanks to the old levee system out here. You'd think the superdome could be cleaner after isaac's wash, but as one member of the crew said, "at least the roof is still on it and there aren't thousands trapped inside." Bill weir, abc news, louisiana. And from bill weir in
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