Cornwall County Council's plan to splash out £160,000 over four years for bottled drinking water has been criticised as a waste of money.
The council says bottled water prevents illness
Councillor Mark Kaczmarek said it was an unsustainable policy despite the bottled water coming from a Cornish spring.
He said it was wrong to waste public money when tap water was available.
The council said that not all council offices have an accessible tap and bottled water prevents illness.
The contract, for £40,000-a-year over four years, comes as the council is cutting the adult social services budget by £2m.
Mr Kaczmarek said: "This is absolutely ridiculous.
"You cannot go on having these luxuries when people are faced with huge council tax bills."
The councillor in charge of corporate support, Brian Higman, said that bottled water could actually save the council money.
He said: "What if the water that came out of the tank was contaminated? That would cost us much more than the water itself.
"If people couldn't get to a tap they could become dehydrated and time off sick would again cost us more.
"It has got to be made as accessible and palatable as possible to save on sickness."