Thousands of people in the Georgetown, South Carolina area have been urged to leave as rivers inundated by Hurricane Florence rainwater threatened to submerge neighbourhoods under three metres of water.

Georgetown, which sits at the confluence of the Waccamaw, Great Pee Dee and Sampit rivers, was largely spared the initial fury of Florence, which came ashore on September 14 as a Category 1 hurricane and killed 46 people in three states.

But the port city of more than 9000 people stands in the path of what the National Weather Service says could be significant flooding as water dumped by the storm system drains to the ocean.

Between 6000 and 8000 people have been advised to leave, but it was not clear how many had done so as of Tuesday evening.

Codey Lamb walks through floodwaters caused by the hurricane last week. Photo: Getty

Parts of Georgetown could be submerged in up to three metres of water in the coming days as the Pee Dee and Waccamaw rivers overrun their banks, the National Weather Service said, adding that the deluge threatened to cut off highways and isolate communities.

The potential flood zone encompasses roughly 3500 homes in Georgetown, 60 kilometres south of Myrtle Beach, and the coastal resort community of Pawleys Island where as many as 8000 people live.

Authorities warned residents in harm’s way with recorded telephone messages and home visits. The county opened two emergency shelters on Monday, and hotels in nearby Myrtle Beach were offering discounts to evacuees. Public schools were closed until further notice.

-AAP