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Puerto Rican officials rushed to evacuate tens of thousands of people downstream of a failing dam and said they could not reach more than half the towns in the U.S. territory as the massive scale of the disaster wrought by Hurricane Maria started to become clear on Friday.
Government spokesman Carlos Bermudez said that officials had no communication with 40 of the 78 municipalities on the island more than two days after the Category 5 storm crossed the island, toppling power lines and cellphone towers and sending floodwaters cascading through city streets.
Officials said 1,360 of the island's 1,600 cell-phone towers had been downed, and 85 per cent of above-ground and underground phone and internet cables were knocked out. With roads blocked and phones dead, officials said, the situation may be worse than they know.
"We haven't seen the extent of the damage," Gov. Ricardo Rossello told reporters in the capital.
More than 15 inches (nearly 40 centimetres) of rain fell on the mountains surrounding the Guajataca Dam in northwest Puerto Rico after Maria left the island Wednesday afternoon, swelling the reservoir behind the nearly 90-year-old dam.
Authorities launched an evacuation of the 70,000 people living downstream, sending buses to move people away and sending frantic warnings on Twitter that went unseen by many in the blacked-out coastal area.
"This is an EXTREMELY DANGEROUS SITUATION," the National Weather Service wrote. "All the areas around the Guajataca River must evacuate NOW. Your lives are in DANGER."
The 316-metre dam, which was built about 1928, holds back a manmade lake covering about five square kilometres.
An engineer inspecting the dam reported a "contained breach" that officials quickly realized was a crack that could be the first sign of total failure of the dam, said Anthony Reynes, a meteorologist with the U.S. National Weather Service.
"There's no clue as to how long or how this can evolve. That is why the authorities are moving so fast because they also have the challenges of all the debris. It is a really, really dire situation," Reynes said. "They are trying to mobilize all the resources they can but it's not easy. We really don't know how long it would take for this failure to become a full break of the dam."
