On Tuesday, the island of Puerto Rico braced itself for one of the worst storms to ever pass through the Atlantic.
On Wednesday, the unincorporated U.S. territory of 3.4 million was spared from the eye of the storm, which passed just north of the island.
Other islands in the Caribbean — such as Barbuda, and two French Caribbean islands, St. Martin and St. Barthélemy — were not so lucky, with Barbuda sustaining damage to 95% of buildings and at least 10 deaths reported across the three islands.
Still, in Puerto Rico the aftereffects of strong winds topping out well over 100 miles per hour, and nearly a foot of water in some areas, has knocked out electricity for more than 1 million people, leaving at least 56,000 without safe drinking water, NBC reports.
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Other estimates put the number of people without potable water on the island at 77,000 and as high as 150,000.
“We’re assuming we’re going to have lots of water shutoffs,” Ruth Santiago, a Puerto Rican environmental activist and attorney, told Bloomberg BNA. “It may be quickly reestablished, but we may have lots of water quality problems.”
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Commonwealth officials said some areas could be without electricity for 4-6 months, the Daily Beast reports. According to the Daily Beast, the island’s water supply “depends entirely on electricity to supply it.”
Officials fear the island could still be at risk of potentially-deadly flooding and storm surges along the coast.
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“As the history with Harvey states,” Puerto Rico governor Ricardo A. Rosselló said in a televised briefing, “flooding can become the major cause of death in events of this nature.”
Tropical storms like Irma also carry with them a host of public health concerns, according to Peter Hotez, the dean of the National School of Tropical Medicine at Baylor College of Medicine, who spoke with Buzzfeed. These include contaminated water from damaged or shut treatment plants, diarrheal diseases, respiratory illnesses from mold, he said.
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The tropical island is particularly vulnerable to climate change, according to scientists. The U.S. Army Corps of Engineers had said US territories in the Caribbean could potentially see a 22-inch rise in sea-level by 2060, which would worsen storm surges and erosion from flooding.
“Puerto Rico needs to take action now, because otherwise, we're going to be dealing with crises," Carmen Guerrero, secretary of the island's natural resources department, said in 2013.
Hurricane Irma is expected to produce dangerous storm surges in the Turks and Caicos islands, as well as the southern islands of the Bahamas, on Thursday, before making its way to the tip of Florida this weekend.