Record floodwaters began slowly receding in Washington state on Friday after triggering evacuations, inundating communities and prompting dramatic rescues from rooftops and vehicles. But authorities warned that waters would still be high for days, and that danger from potential levee failures remained. "This is not just a one- or two-day crisis," Gov. Bob Ferguson said at a news briefing. "These water levels have been historic, and they're going to remain very high for an extended period of time." President Donald Trump has signed the state's request for an emergency declaration, Ferguson said. An unusually strong atmospheric river dumped a foot (30 cm) or more of rain in parts of western Washington over several days and swelled rivers. No deaths have been reported, Ferguson said.