Local newspaper Le Dauphine reported that the man had dropped his wallet down the sewer in an underground car park and went to retrieve it.
While doing so he slipped, ending up with his head in the sewer and his legs sticking out the top. He was unable to move from the space, just 40 centimetres wide and 1.5 metres deep.
The 40-year-old was stuck in the same position all night until someone using the car park spotted his feet sticking out of the sewer the next morning.
The passer-by called the emergency services who pulled out the man and resuscitated him. He was suffering from hypothermia and was taken to hospital for treatment.
Unfortunately for the man, there were yet more problems in store. Police also spotted that he had been siphoning off waste oil from his car into the sewer at the time.
Disposing of waste oil in this way is an offence in France, with serious cases risking up to two years in prison and a fine of €76,000 ($97,000).