Hours after calling for evacuations and saying the failure of Beaver Creek Dam in Columbia was imminent, authorities said they had managed to stabilize the dam and that evacuations were voluntary.
But officials cautioned that the evolving situation only served to highlight the repercussions of extreme rainfall, even long after the sunshine has returned.
"Things are about to get worse on the coast," Gov. Nikki Haley told reporters Wednesday. "It's not over yet."
Two people who went missing in floodwaters earlier Wednesday were found dead, according to the Richland County Sheriff's Department.
Lt. Curtis Wilson told CNN the two victims were in a truck with three other people when it washed away.
Haley told reporters earlier that the victims were part of a work crew that drove around a barricade and their truck was overcome by water.
"While sun is out," she said, "this event is not over... Do not move barricades."
So far, at least 19 people have died in weather-related incidents: 17 in South Carolina and two in North Carolina.
At least 600 rescues of people and animals have been made, Haley said. More than 300 people were still staying in 23 shelters.
The past two days have been "very tenuous," said Jim Lehman, a member of the Beaver Dam Lake Owners Association and an area homeowner.
Haley declined to address questions about the state's infrastructure, saying the focus was on response and recovery and that the broader issues will be looked at later.
A day earlier, the governor refused to provide an estimated cost of the damage -- which she called "disturbing" -- but said state and Federal Emergency Management Agency officials were making assessments.
"It's hard to look at the loss we're going to have," she said. "This could be any amount of dollars."
More than 400,000 of the state's 4.8 million residents were under a boil-water advisory, which affects about 16 water systems, said Jim Beasley, a spokesman for the S.C. Emergency Response Team.
At least 13 dams have failed since Saturday, Haley said. Another 62 dams were being monitored.
One failure, of the Overcreek Bridge dam in Forest Acres, sent a torrent of floodwater raging downstream and forced evacuations in the city, which adjoins Columbia.
Officials allowed water to breach at least one other dam, also in Richland County. Officials conduct these controlled breaches "to prevent a much larger incident and a much larger amount of water escaping from the dam," emergency management spokesman Derrec Becker said.
Haley said National Guard members were helping with sandbagging operations and other mitigation efforts.
A 13-mile section of Interstate 95, which cuts through the eastern part of the state, remained closed.
The flooding is far from over. Rivers might not crest for another two weeks, CNN meteorologist Chad Myers said.
And the mayor of Columbia, who has said he believes damage "will probably be in the billions of dollars," is bracing for more trouble.
"We aren't close to being out of the woods," Mayor Steve Benjamin said Tuesday, adding that even more dams could be in danger of breaking or being topped by water. "We still expect the water to start coming down from the Upstate, coming downhill to the Midlands."
The situation is the result of a weather system that funneled tropical moisture into South Carolina last week and refused to move on, Myers said.
"It was a garden hose that just kept pouring ashore in one spot, and that spot was South Carolina," he said.
Saturday's college football game between South Carolina and Louisiana State -- which was to be played in Columbia -- has been relocated to LSU's home field in Baton Rouge, the University of South Carolina athletics department said in a statement.
"Yesterday, we made the extremely difficult decision to cancel classes for the week due to the stress 34,000 students would place on the region's recovering infrastructure," university President Harris Pastides said. "There is no doubt 85,000 fans would exact the same toll."