Authorities ordered more than 50,000 people to leave parts of Fort Bend County, about 35 miles (55 km) southwest of Houston as the Brazos River was set to crest at a record high of 59 feet (18 m) this week, 14 feet above its flood stage.
Brazos County Judge Robert Hebert told reporters the forecast crest represents a high not seen in at least 800 years.
“What we’re seeing is the most devastating flood event in Houston’s recorded history,” said Steve Bowen, chief meteorologist at reinsurance firm Aon Benfield.
Total precipitation could reach 50 inches (127 cm) in some coastal areas of Texas by the end of the week, or the average rainfall for an entire year, forecasters said. Nearly 24 inches fell in a span of 24 hours in Baytown, a city home to major refineries about 30 miles east of Houston, the National Weather Service said early on Monday.
“Water started flooding our house and by last night we were unable to leave,” said Maria Davila, one of about 1,000 people in a makeshift shelter at Houston’s sprawling convention center.
U.S. President Donald Trump plans to go to Texas on Tuesday to survey damage from the storm, a White House spokeswoman said on Sunday.
Trump, facing the first big U.S. natural disaster since he took office in January, signed a disaster proclamation on Friday, triggering federal relief efforts. Texas Governor Greg Abbott said on Sunday 54 counties had been declared state disaster areas and he plans to add 1,000 more National Guard personnel to the flood battle.
Harvey is expected to produce an additional 15 inches to 25 inches of rain through Friday in the upper Texas coast and into southwestern Louisiana, the National Hurricane Center said.
“The storm isn’t moving much. If it doesn’t move much, it keeps throwing rain into the same area,” Steve Wistar, a senior meteorologist with AcuWeather, said in a telephone interview.
Katrina resulted in more than $15 billion in flood insurance losses in Louisiana and Mississippi.
Flood damage in Texas from Hurricane Harvey may equal that from Katrina, the costliest natural disaster in U.S. history, an insurance research group said on Sunday.
The Gulf is home to almost half of the nation’s refining capacity, and the reduced supply could affect gasoline supplies across the U.S. Southeast and other parts of the country. Shutdowns extended across the coast, including Exxon Mobil’s Baytown refinery, the second largest U.S. refinery.
The outages will limit the availability of U.S. crude, gasoline and other refined products for global consumers and further push up prices, analysts said.
All Houston port facilities will be closed on Monday because of the weather threat, a port spokeswoman said.
More than 224,000 customers in the Houston area were without power on Monday morning, utilities CenterPoint Energy and AEP Texas said.
Houston’s George Bush Intercontinental Airport, one of the nation’s busiest, and William P. Hobby airport halted all commercial flights on Sunday. The airports remained closed to commercial traffic on Monday.
Jose Rengel, a 47-year-old construction worker who lives in Galveston, helped rescue efforts in Dickinson, southeast of Houston, where he saw water cresting the tops of cars.
“I am blessed that not much has happened to me, but these people lost everything. And it keeps raining,” he said.
“The water has nowhere to go.”