"It has been raining non-stop for 10 hours... And the result is what you see," the 49-year-old warehouser worker told AFP in Ribarroja del Turia, pointing to flooded streets caked in mud.

"We are cut off, you can't reach parts of the town. The roads are all cut, bridges are cut."

Rellan lives in a town on the outskirts of the Mediterranean coastal city of Valencia, whose region bore the brunt of the damage and more than 90 deaths announced nationwide.

The local Turia river was a roaring torrent of swollen, brownish water that was flowing close to the top of a main bridge when AFP visited on Wednesday.

Stranded motorists loitered outside their vehicles as a huge tailback snaked along the motorway leading out of the town during severe disruption to road transport.

"It had been a long time since this happened and we're scared," said Esther Gomez, a Socialist town councillor in Ribarroja del Turia.

We went from "being in a place where nothing is happening to there being such a huge flood" in a matter of minutes, the 57-year-old told AFP.

The inaccessibility of flooded roads and damage to communications and power infrastructure have complicated an already herculean task for the rescue services.

"The emergency and security services were also overwhelmed, because so many places were affected that they couldn't get to all the places," Gomez said as she remembered a chaotic night.

The sudden surge of the waters in nearby streams flooded the town's industrial estate and left workers stuck there overnight "with no chance of rescuing them", she said.

- 'Nothing left to save' -

In the Valencia region town of Utiel, the storm dumped 230 mm of rain on Tuesday -- three times the previous daily record, according to national weather agency AEMET.

That represented a quantity of water almost six times greater than what the area receives on average for the whole month of October.

"There's nothing left to save, I lost everything in one night," Utiel resident Emilio Munoz told AFP in front of his small red-brick house.

The pensioner in his 70s had just finished cooking when the water seeped into his home "and overturned everything", with branches and leaves hanging from his dining room chandelier.

Diggers ploughed through thick layers of mud on the roads to allow rescuers to move through the town littered with uprooted trees and upended cars.

A wave of solidarity saw young volunteers moving door to door to check up on the vulnerable. "We must help our elders, we can't hang around doing nothing," said Ricardo, 16.

Standing near the overflowing Magro river, a frustrated Sonia Alvarez pointed to her floating car and bemoaned the unavailability of a tow vehicle to save it.

Her three children and husband are in Valencia city, but with the roads cut off she had no choice but to spend the night alone.

Maria Hernandez, 70, was simply grateful to survive after the floods spared her home. "I had the fright of my life. Thank God, I am live," she told AFP.