san juan many people live near crumble dam storm-battered puerto rico evacuate governor ricardo rossello say monday ask government aid avert humanitarian crisis hurricane maria much caribbean island u.s. territory population 3.4 million still without electricity five days maria strike ferocious wind torrential rain powerful hurricane hit puerto rico nearly century grow concern 70,000 people live river valley guajataca dam island northwest crack see friday 88-year-old earthen structure rossello say work assumption 120-foot 35-meter dam would collapse rather wrong front nothing fail cost people live say interview cnn people near vicinity evacuate unclear governor say 70,000 valley inhabitants leave area several hundred people live small towns close dam 320 people towns move safety accord local media fear potentially catastrophic dam break add immense task face disaster relief authorities maria second major hurricane strike caribbean month storm kill least 29 people region least 10 puerto rico already battle economic crisis rossello say storm strike embark aggressive fiscal agenda include 1.5 billion cut game changer tell cnn completely different set circumstances need take consideration otherwise humanitarian crisis brock long administrator federal emergency management agency fema tom bossert senior adviser department homeland security meet rossello monday white house spokeswoman sarah sanders tell reporters washington administration engage fact-finding process figure much help puerto rico need federal response anything slow sanders say daily brief fact unprecedented push billions dollars federal assistance administration fight many structure puerto rico include hospitals remain badly damage flood clean drink water hard find areas plan able land take damage airports storm also put big strain prepa island electricity utility declare bankruptcy july accumulate billion debt years underinvestment preliminary fema report estimate 55 percent transmission tower may 90 percent distribution system could destroy 91 percent puerto rico cellphone sit also service federal communications commission say 10,000 federal staff include 700 people fema recovery work puerto rico u.s. virgin islands accord fema national weather service warn flash flood west island monday thunderstorms move maria would likely downgrade hurricane tropical storm tuesday night national hurricane center say p.m. edt 1800 gmt monday center say 300 miles 480 km south-southeast cape hatteras north carolina head slowly north storm unlikely hit continental unite state directly nhc say large swell affect u.s. east coast tropical storm warn effect much north carolina coast officials issue mandatory evacuation order visitors ocracoke island out bank go effect a.m. edt 0900 gmt monday puerto rico evacuate area near crumble dam ask aid