Tropical Storm Florence crawled through the Carolinas on Saturday, causing catastrophic flooding, deaths and damage — including a torrent of partially treated wastewater that spilled into a major river.

The spill and the threat to the large and environmentally precarious hog industry and tobacco crops are among the dangers as the storm creeps inland at 2 mph (3 kph). A deluge is forecast, and more than 2 1/2 feet of rain has already fallen across southeastern North Carolina, the National Hurricane Center said.

“We face walls of water at our coast, along our rivers, across farmland, in our cities, and in our towns,” Governor Roy Cooper said in a briefing Saturday. “The rainfall is epic and will continue to be.”

Florence, the first major hurricane of the Atlantic season, is expected to cause an estimated $18 billion in damage. More than 691,000 customers were without power in the Carolinas as of 2 p.m. local time, according to utility websites. North Carolina alone had at least 616,000 customers with outages at that hour. About 20,000 have sought protection in the state’s shelters, and hundreds had to be rescued in New Bern alone. The water closed Interstate 95, a highway that stretches from Maine to Florida.

Three rivers in the state have hit “major flood stage,” and an additional 13 threaten to follow suit, including six by this evening, according to emergency officials. In Wilmington, an estimated 5.25 million gallons of wastewater spilled into the Cape Fear River from a treatment plant when two generators failed Friday, according to Bridget Munger, a spokeswoman for the state’s Department of Environmental Quality.

Significant Spill

A spill of 5.25 million gallons is significant when most are measured in the thousands, said Matthew Starr, the Upper Neuse Riverkeeper at Sound Rivers, an advocacy group. “That is a tremendous negative impact on our water,’’ Starr said.

Partially treated wastewater carries not only bacteria that can harm humans and wildlife, but also the chemicals being used to clean it. Human waste isn’t the only danger: North Carolina is the nation’s second-largest hog producer, and farms process feces in ponds laced with bacteria that break down the noisome mess. Though farmers hurried to pump out their lagoons, record flooding risks spreading contamination widely.

While floods are the most pressing threat, wind and water have already proved deadly. North Carolina officials reported fatalities including a mother and infant and a man killed while connecting a generator. In South Carolina’s Union County, a 61-year-old woman died when she drove into a tree toppled by the storm. Read More: Drone Army Ready to Swoop in for Power Recovery

In New Bern, North Carolina, hundreds of people were rescued — some by air — as water poured into homes and submerged cars. Beatrice Soliman of Houston said it had been more than 36 hours since she heard from her daughter, who lives with her husband, two children and two dogs, in Hubert, an hour east of New Bern.

“I’m nervous, I’m shaky and I haven’t eaten for two days,” Soliman said, adding that she had to turn off the television news coverage as the death toll rose. “I just want a text.”

Making Preparations

Portions of the region not yet inundated made ready. Behind West Lumberton Baptist Church in Robeson County, North Carolina, a pair of John Deere front-end loaders raced to build a levee of sand and gravel over CSX railroad tracks. The area saw flooding from the Lumber River during Hurricane Matthew two years ago.

In Charlotte, the largest city in the storm’s path and banking capital of the South, officials expected a record 12 inches of rain, and Mayor Vi Alexander Lyles said her biggest concern is 2,400 properties in the flood plain.

In South Carolina, more than 40 flamingos at the Riverbanks Zoo and Garden were carried, one by one, from their outdoor enclosure, their necks craning over the shoulders of staff members, according to a video posted by ABC News. The birds wandered around a secured room equipped with a blue plastic paddling pool for comfort.

The storm was about 60 miles west of Myrtle Beach, South Carolina, at 4:45 p.m local time Saturday, according to the National Hurricane Center. Top sustained winds were 45 mph, and it could maintain tropical-storm strength for another 24 hours, according to the latest advisory. The rain total could reach 40 inches in some places.

“It is probably a foregone conclusion at this point that Florence is going to set the state records for both North and South Carolina,’’ said Steve Bowen, director and meteorologist at Aon Benfield Analytics in Chicago.

In the Path

The total bill for damage may reach $18 billion, lower than earlier estimates, said Chuck Watson, a disaster researcher at Enki Research in Savannah, Georgia. That includes $15 billion for North Carolina, $2 billion for South Carolina and $1 billion elsewhere.

As of July, 134,306 flood-insurance policies had been issued in North Carolina for $33.7 billion in property, the vast majority along the coast, according to Aon Benfield. The region’s population has been rising, and since 2000, at least 19 counties in North Carolina and South Carolina have seen more than 25,000 residential units built, the report said.

The states’ agriculture economies are also at risk. North Carolina is forecast to harvest 158,800 acres of tobacco this year, and it’s the nation’s top producer. Half the eastern North Carolina crop “will be basically destroyed, blown away,” Larry Wooten, president of the state’s Farm Bureau, said Saturday.

More than 60 swine operations house more than 235,000 hogs that generate almost 202 million gallons of waste per year within the floodplain of North Carolina’s coast, according to Waterkeepers, a watchdog group. Environmental organizations are preparing to inspect waterways for toxic spills from lagoons and coal-ash ponds at power plants once the storm subsides.

More than 40,000 utility workers from at least 19 states are ready to restore power, according to a news release from the federal energy department. Besides Duke Energy, utilities in the Carolinas include South Carolina-owned Santee Cooper, Brunswick Electric Membership Corp., Jones Onslow Electric Membership and Lumbee River Electric Membership.

Florence will be a test of the Trump administration’s ability to respond to disaster, which has been a sensitive topic. President Donald Trump said before the storm that the government is “as ready as anybody’s ever been.” But he also complained Friday night that the death toll from last year’s Hurricane Maria in Puerto Rico was inflated in order to hurt him. He said the federal response to that storm, which killed almost 3,000 people, was an “unsung success.”

The president plans to visit areas hit by Florence early next week once officials determine the trip won’t disrupt rescue and recovery efforts, spokeswoman Lindsay Walters said. But for now, the struggle belongs to those in the storm’s path.

“New Bern would qualify as apocalyptic,” Will Hargett, a livestock broker based in Greenville, North Carolina, said in a text message Saturday after leaving his home earlier in the week to take shelter on his family’s farm in Jones County. “We’re just playing Noah up here.”