KINSTON, N.C. (Reuters) - Residents of Georgetown County, South Carolina, where five rivers flow into the ocean, were preparing on Friday for a deluge of water in the aftermath of Hurricane Florence, which has killed at least 40 people.

The county of 60,000 people, on the Atlantic coast between Myrtle Beach and Charleston, is one of several areas in the Carolinas waiting anxiously for rivers to crest, a week after Florence dumped some three feet of rain on the region.

Flooding could begin early next week, officials said during a community meeting on Thursday. The city of Georgetown on Friday was handing out 15,000 sandbags as the county develops plans to evacuate residents.

"Please heed the warnings,” Sheriff Lane Cribb said. "Protecting lives and property will be our goal ... You better pray.”

Thirty-one deaths have been attributed to the storm in North Carolina, eight in South Carolina and one in Virginia.

More than three dozen flood gauges in North and South Carolina showed flooding, according to the National Weather Service.

Some 4,700 people across North Carolina have been rescued by boat or helicopter since the storm made landfall, twice as many as in Hurricane Matthew two years ago, according to state officials. About 10,000 remain in shelters.

The coastal city of Wilmington, North Carolina, remained cut off by floodwaters on Thursday, and more than 200 state roads were closed or blocked. More than 54,000 homes and businesses were without power in the Carolinas on Friday afternoon.

As floodwaters continued to rise, concerns grew about environmental and health dangers.