Members of the Australian Services Union handed out bottles of water outside the office of Kiama MP Gareth Ward on Saturday, part of an action calling for the state government to rule out privatising Sydney Water.
A dozen union members spent the morning outside Mr Ward's office on Terralong Street, Kiama, in the latest leg of a campaign protesting any moves to sell off the water provider.
ASU NSW assistant secretary Ben Kruse said the union had been unsatisfied with government rhetoric around Sydney Water.
"The concern is the government won't rule out privatisation. Their response was there were 'no plans' to sell it," Mr Kruse said.
"We're calling on Gareth to say what that means. The term 'no plans' is a codeword for 'flog it off at the first opportunity'."
Mr Ward said he was confused by the action, saying the government had "absolutely no plans" to sell off Sydney Water.
"I can understand their concerns, but the concerns are unfounded," Mr Ward said.
"The premier has ruled it out in parliament. We're taking to the next election, and being very honest about, plans to lease electricity poles and wires. Why wouldn't we be honest about this?"
"Any other claims are erroneous and incorrect."
Mr Kruse said the ASU was travelling to offices of each government member to campaign for Sydney Water to remain in public hands. He said privatisation of public water utilities around the world had led to problems including the release of sewage, cryptosporidium and chemicals into water supplies.