Australian singer Casey Donovan is among thousands of music fans stuck in foot-deep mud and with no working toilets in the Nevada desert after a freak storm turned the Burning Man festival into a muddy mess.

The annual festival, which attracts up to 80,000 artists, musicians and activists for a mix of wilderness camping and avant-garde performances, has turned into a muddy disaster after 150 millimetres of rain at the usually dry and dusty Black Rock Desert site.

More rain was due over the weekend, with stranded festival-goers told to conserve food, water and fuel after a vehicle ban was imposed.

The festival’s toilets were also out of use, revellers said, because the service vehicles could not drive through the mud to empty them. One festival-goer later told the BBC that organisers had since been able to empty and restock at least some of the toilets.

Organisers closed the festival to vehicles after the death of a person. The Pershing County Sheriff’s Office said on Sunday (US time) it was “currently investigating a death which occurred during this rain event” but gave no further details on the circumstances.

Donovan said it was “not such an ideal situation”.

“We are safe, we have food and ‘dryish’ shelter. It is very moist here and forecast is for more rain over the next few days,” she posted to her Instagram late on Sunday (AEST).

“Fingers and toes crossed for some sunshine to clear things up.”

Officials said late on Saturday they didn’t know when the roads would “be dry enough for RVs or vehicles to navigate safely”, but they hoped vehicles could depart by late Monday if weather conditions improved.

The closures came just before a large wooden effigy was supposed to have been burned on Saturday night. Organisers said that all burning had been postponed, and authorities were working to open exit routes by the end of the US holiday weekend.

With their party closed to motorised traffic, attendees trudged through mud, many barefoot or with plastic bags on their feet. Most remained hunkered down at the site, although a few managed to walk several kilometres to the nearest town or catch a ride there.

DJ Diplo posted a video to Instagram on Saturday night showing him and comedian Chris Rock riding in the back of a fan’s ute. He said they had walked nearly 10 kilometres through the mud before hitching a ride.

“I legit walked the side of the road for hours with my thumb out,” wrote Diplo, whose real name is Thomas Wesley Pentz.

US President Joe Biden said in Delaware on Sunday he was aware of the situation, including the death, and the White House was in touch with local officials.

-with AAP