In return for allowing tourists to have a free drink from their water supply, cafes will be promoted on the Tiki Wai website.
Tiki Wai is also producing cups made out of polypropylene. People who buy a cup can go to the Tiki Wai website, or download the Tiki Wai app, where they will be "geolocated" and given a list of nearby cafes.
Mr Everton said the cup was not yet available in Wanganui. There were also no Wanganui cafes participating in the Tiki Wai project, although there were 200 cafes throughout the country taking part.
"However, we hope to soon add New Plymouth and Wanganui to the scheme," he said.
Several cafes spoken to by the Chronicle said they were open to providing tourists with free water, and one already does.
Mark Dyhrberg, owner of Jolt cafe, said his cafe already provided free mineral water to customers and had done so for about seven years.
He said the cafe sometimes had tourists come in to ask if they could use the tap to fill bottles with fresh water.
"The majority of them are customers - they'll come in and have a coffee - so we don't mind."
Chris Voyles from Cactus Creme Cafe said he had no objection to allowing tourists to use the cafe's tap. However there was a problem with the location of the tap.
"They'd have to come right through into our kitchen, and that could be difficult."
Mr Voyles said there was a tap on the outside of the cafe, but it had no handle, so it couldn't be used.
"I presume it is up to the council to fix it," he said.
Meanwhile, a new fresh-water drinking fountain has been installed on the riverbank, near the visitor information centre.
Formally opened on Saturday by Mayor Annette Main, Councillor Rob Vinsen and Ed Boyd from sponsor H&A; Print, the drinking fountain provides a drinking spout, a tap for filling up bottles, and even a tap to fill up a built-in dog bowl.
To find out more about Tiki Wai, or to make your fresh water available, visit www.tikiwai.com.