By 2030, rising sea levels may put 4,000 miles of fiber optic cable along the U.S. coasts underwater, threatening to upend the nation’s internet infrastructure, . Most internet cables are underground, making them particularly vulnerable to flooding. And while some of these cables are outfitted to withstand water, not all of them are prepared for the rising tides. What can telecom giants do? Install weather-resistant cables. Also, they can come up with many ways to reroute the internet.