Updated

Both sides of Interstate 10 in a remote desert area of Southern California were closed late Sunday after heavy rains washed away an elevated portion of the highway, injuring a motorist.

The California Highway Patrol confirmed to the Los Angeles Times that approximately 30 feet of the eastbound roadway "is washed away and bridge is gone." The Tex Wash bridge carries traffic 15 feet above a normally dry desert wash about 50 miles west of the Arizona border.

The westbound side of the freeway remained intact, but California transportation officials said that it, too, had been badly compromised by flooding. California Department of Transportation (Caltrans) spokeswoman Terri Kasinga told the Associated Press that Interstate 10 would remain closed between Corn Springs and Chiriaco Summit "completely and indefinitely."

The closure will force motorists seeking to use I-10 to travel between California and Arizona to go hundreds of miles out of their way to Interstate 8 to the south or Interstate 40 to the north. Transportation officials recommended travelers on the east side of the collapse use U.S. Highway 95 in Arizona to get to the other freeways, and that in California drivers use state routes 86 and 111 to get to Interstate 8 into Arizona.

Busy I-10 is the most direct route between the Los Angeles area and Phoenix. An average of more than 20,000 cars per day pass through the area that is shut down, according to federal highway statistics.

Kassinga said says engineers won't even be able to properly assess the damage to the two sides until Monday morning, and offered no timeframe for their opening again.

"The 10 is a dire situation," Kasinga told the Riverside Press-Enterprise earlier Sunday.

The Riverside County Fire Department said it had to extract a driver who crashed a pickup truck in the collapse. The person was taken to a hospital with moderate injuries. A passenger from the truck was able to get out without help and wasn't hurt.

Pamala Browne, 53, and her daughter were driving from Flagstaff, Arizona to Palm Desert, California when they got stranded when the westbound lanes were shutdown.

"Oh my God, we are so stuck out here," Browne told the Desert Sun newspaper.

She said "we're talking miles" of cars waiting for a route to open.

The Desert Sun reported that the Tex Wash bridge, which opened in 1967, had been listed as functionally obsolete in the 2014 National Bridge Inventory.

The rains came amid a second day of showers and thunderstorms in southern and central California that were setting rainfall records in what is usually a dry month.

Rain fell Sunday afternoon in parts of Los Angeles County's mountains, the valley north and inland urban areas to the east as remnants of tropical storm Dolores brought warm, muggy conditions northward.

The showers forced the Los Angeles Angels' first rainout in 20 years and the San Diego Padres' first rainout since 2006.

Saturday's rainfall broke records in at least 11 locations, including five places that had the most rain ever recorded on any day in July, said National Weather Service meteorologist Joe Sirard.

July is typically the driest month of the year in Southern California. Because of that, Saturday's 0.36 inch of rain in downtown Los Angeles exceeded the 0.24 inch recorded July 14, 1886, which had been the wettest July day in nearly 130 years.

The storm brought weekend flash floods and power outages and turned Los Angeles County's typically packed coast into empty stretches of sand when the threat of lightning forced authorities to close 70 miles of beaches.

Meanwhile, the summer storm has helped firefighters advance on two wildfires that broke out Friday. The Los Angeles Times reported that the 3,500-acre North fire that had shut down Interstate 15 Friday, burning cars and stranding motorists, was 75 percent contained by Sunday morning.

Muggy, moist conditions were expected to persist through Monday.

The Associated Press contributed to this report.