san juan puerto rico dam puerto rico weaken heavy rain hurricane maria danger fail sunday pose flood threat thousands home downstream storm-battered u.s. island territory struggle fifth day virtually electricity 70,000 people inhabit river valley guajataca dam northwestern corner island evacuation order since friday afternoon authorities first warn earthen structure danger imminent collapse fear potentially catastrophic dam break add pandemonium face disaster relief authorities aftermath maria claim least 29 live across caribbean accord officials media report puerto rico governor ricardo rossello personally urge residents area heed evacuation order survey damage dam saturday tell reporters fissure structure become significant rupture dam stand 120 feet 37 meter tall build 1929 supply surround region hydropower drink water irrigation supply national weather service san juan island capital extend flash flood watch communities along rain-swollen guajataca river dam midday sunday dam fail flood would life-threatening weather service warn stay away sweep away say maria second major hurricane savage caribbean month powerful strike puerto rico nearly century carve path destruction island plow ashore early wednesday arrive category storm saffir-simpson wind scale top wind 155 mph 249.5 kph maria rip roof build turn roads gush debris-strewn rivers knock power across entire island home 3.4 million people lose house completely flood say resident carmen gloria lamb resident near rain-swollen guajataca lose everything cars clothe everything puerto rico officials officially confirm 10 storm-related fatalities island hurricane blame least 19 deaths across caribbean bulk devastate island nation dominica severe flood structural damage home loss electricity except backup generators three press problems face puerto ricans new york governor andrew cuomo whose state home many puerto rican descent say tour island terrible immediate situation require assistance federal government financial assistance say cnn saturday even island medical facilities leave precarious shape many hospitals flood strew rubble run critically low diesel fuel need keep generators operate evacuation u.s. mainland option patients sign strain puerto ricans evident throughout san juan capital drivers wait seven hours fill station open saturday accord news report water ration also begin saturday sign post throughout san juan old town inform residents service would return two hours notice telephone service also unreliable many island cell tower damage destroy sunday morning governor tell reporters officials would continue clear roads bridge block storm would join supply delivery mission caguas small city mountains south san juan storm cause estimate 45 billion damage lose economic activity across caribbean least 30 billion puerto rico say chuck watson disaster modeler enki research savannah georgia maria hundreds miles km east florida atlantic ocean sunday downgrade category storm expect weaken move north atlantic east coast next two days maria hit puerto rico two weeks hurricane irma one powerful atlantic storm record kill 80 people caribbean unite state two storm follow hurricane harvey also kill 80 people strike texas late august cause flood houston weaken dam loom late threat puerto rico hurricane