Whanganui District Council three waters manager Kritzo Venter said an incidental water leak caused the fountain.
The leaking pipe was exposed and repaired by Veolia staff, he said.
Council contractors have been replacing the 100-year-old stormwater pipeline along part of Smithfield Rd, Konini St and London St with an upgraded system.
However, Venter said the section of water infrastructure where the fountain occurred was not part of the network being replaced, nor would the incident interrupt the council’s work programme in the area.
There were no plans to replace the section of pipes in the future.
Finn Williams is a multimedia journalist for the Whanganui Chronicle. He joined the Chronicle in early 2022 and regularly covers stories about business, events and emergencies. He also enjoys writing opinion columns on whatever interests him.