They will be joined by the resident tortoises but the fish have been taken out and will not be replaced.

Orange City Council spokesman Allan Reeder said the ponds would be filled and cleansed ready for the Australia Day activities on Sunday.

Truckloads of bore water were being pumped into the ponds this week.

"The silt at the bottom of the ponds was pumped out by a trade waste contractor last week," he said.

"Since then the weekend storms helped with rinsing out any remaining sediment."

Council staff have also been removing overgrown plants and weeds from the islands in the ponds.

"The process of re-filling the ponds with tankers of bore water began on Tuesday," Mr Reeder said.

He said the filling would be completed to give the water time to settle before Sunday's events.

"The tortoises and ducks that live around the ponds have been spotted nearby and they seem to be coping with the disruption," he said.

On Tuesday ducks were seen sitting in shade next to the pond waiting for staff including horticulturalist Phil Tiefel to complete the work.

Mr Reeder said council did not want to return fish to the water and did not want people to dump unwanted fish in the ponds as had previously occurred.

He said a contractor had removed about 40 large, live fish. "The ponds have not been built with aeration that's needed to put oxygen into the water and are generally not designed for fish. There are no plans to add fish to the water again," he said.