CHARLOTTE, N.C. — A system of thunderstorms across western North Carolina stalled on Saturday and dumped about a foot of rain on the area, causing power outages and flash floods that swamped homes and washed out roads and bridges.

There were 18 reports of swift-water rescues, and one minor injury, said Jim Dickerson, spokesman for Catawba County Emergency Services. He did not have details.

Hickory Mayor Rudy Wright urged residents to stay indoors and away from flooded roads, The Charlotte Observer reported (http://bit.ly/1buP7OY).

"This is a time for all of us to be very careful and patient," he said. "The cleanup is going to take a while."

Parts of Catawba and surrounding counties were under water Saturday. Catawba County officials said some of the worst flash flooding in decades followed a nearly stationary weather system that dumped 10 inches of rain in about six hours.

Officials closed 65 roads in Catawba County by Saturday afternoon. At least six will remain closed for up to three months to repair damage, Dickerson said.

A full damage assessment will begin Sunday, he said.

High Shoals Lake in Catawba County rose nearly five feet over a 10-hour span. Officials said high water will move down the Catawba River later Saturday, possibly causing more flooding. The rain had stopped in the area by late afternoon Saturday. The National Weather Service said the heavy rain will move east across the western piedmont of North Carolina and northeastern South Carolina.

Several miles of Interstate 85 in Cabarrus County was closed for a short time due to high water. Traffic moved at a crawl along both I-85 and Interstate 77 north of Charlotte as drivers navigated water several inches deep in spots. In Lincoln County, there were reports of up to three feet of water covering roads.

Duke Energy reported about 5,000 power outages.

It is at least the fourth major flash flooding event in the Charlotte region in the past month. Highway officials already are working to repair more than a dozen Charlotte-area roads damaged by previous flooding.