SAN JUAN, P.R. — More than half a million Puerto Ricans were still without electricity on Friday, three days after an earthquake shook the island and led thousands of people to sleep outside for days, fearing more tremors.
The island of 3.2 million people lost power immediately after the magnitude-6.4 earthquake on Tuesday, and electrical crews have worked around the clock to ramp up additional electricity generation to replace a major power plant that was heavily damaged.
The Costa Sur plant, located in the southern town of Guayanilla, had “destruction on a grand scale,” said José Ortiz, executive director of the Puerto Rico Electric Power Authority.
One person was directly killed by the earthquake, but at least three people have died of apparent heart attacks that may be related to the earthquake’s effects, local officials said on Friday.
The deaths prompted fears that the southern part of the island — where thousands of people are in the dark and on the street — could face serious health problems in the wake of the disaster, as occurred in the months after Hurricane Maria struck in September 2017.
When customers went without electricity for as long as a year after that storm, people died of heart attacks in line at gas stations; those dependent on oxygen machines went without lifesaving equipment; bacterial diseases spread; and seriously ill patients succumbed to their diseases.
Mayor Ángel Luis Torres of Yauco, a town near the quake’s epicenter, said that one man had died in his home on Wednesday and that another woman died early on Friday morning at a makeshift encampment in the Barina neighborhood. It was unclear if the man’s home had been damaged by the earthquake.
The woman, Vidalina Pacheco, 92, had hypertension and was one of thousands of Yauco evacuees spending the night outside, fearing more temblors. Only some people have heeded the authorities’ pleas to stay with relatives or sleep at government-run shelters. Ms. Pacheco was not at the local shelter, the mayor said.
Another woman, Noelia Artruz Lugo, 76, was found dead on Friday in Guayanilla, a neighboring town, according to Evelio Torres, an aide to the town’s mayor. Mr. Torres said that part of Ms. Artruz’s house had collapsed on Wednesday, the day after the big earthquake, and that she was found in the bathroom, dead of an apparent heart attack.
The only death directly linked to structural damage occurred in Ponce, where Nelson Martínez, 73, died when an unfinished bathroom wall fell on him while he was in bed.
Since the quake, thousands of people in southern Puerto Rico have been spending nights outside — in hammocks, on inflatable mattresses and in tents. Fearing additional tremors, many Puerto Ricans are too afraid to sleep in their own homes. At least 6,000 more quake survivors are in shelters, said Jenniffer González-Colón, Puerto Rico’s representative in Congress.
“We’re used to hurricanes,” she said. “We’re not used to earthquakes.”
Dozens of tremors have been felt in the days since the pre-dawn quake tumbled houses and schools.
The crisis that has again plunged Puerto Rico into darkness was caused when the island’s power plants shut down automatically after the tremors. Officials discovered that one of the biggest plants was so damaged that it could not be immediately repaired.
By Friday morning, about 20 percent of the Puerto Rico Electric Power Authority’s roughly 1.5 million customers remained without power, the utility said, but it was far from clear when the remaining customers would have electricity again. Gov. Wanda Vázquez said this week that she could not provide a date for when the power would return to all of the island’s residents.
The damaged Costa Sur plant, which produces more power than any other plant on the island, could take a year to repair, Mr. Ortiz said at a news conference on Thursday. Other plants may come back online by Sunday, Mr. Ortiz said, but he warned that the system would remain unstable for several weeks.
“In the coming hours and days, we should have 100 percent power back,” Mr. Ortiz said.
Patricia Mazzei reported from San Juan, P.R., and Frances Robles from Miami. Alejandra Rosa contributed reporting from San Juan and Nicholas Bogel-Burroughs from New York.