this city have worked so hard to rebuild could be gone once again. >> i think we're in big trouble, even with a category 2 or 3. i don't know how much trouble, but big trouble. category 5, we're in big, big, big trouble over again. >> the ballpark figure for protecting the city from a category 5 hurricane, the so-called one in 1,000 year storm protection, is somewhere between $70 billion and $140 billion. >> all things are possible, given the mission and the financial backing to do it. >> building bigger levees isn't the only solution. to succeed, any plan needs to include coastal wetlands restoration. the island's marshes and swamps absorb a hurricane strength and the storm surge before it reaches the city. >> the barrier islands protect the wetlands. the wetlands protect the levees. the levees protect us. >> but louisiana's wetlands are