An October 2021 cease-to-flow date for Burrendong Dam may have to be changed as recent rain is likely to boost its contents to 30 per cent of storage capacity within days.
It's two years since the dam held that much water.
On Wednesday morning the dam was holding 361 gigalitres (GL) of water and sitting at 28.3 per cent of capacity, up from 24.9 per cent on Friday, July 24.
A WaterNSW spokesman said the dam had received 13GL of water in the previous 24 hours with inflows expected to continue for days, predominantly from the Macquarie River upstream of the dam, but also via the Cudgegong River.
"The catchment has reached a point where the volume and frequency of rain events has been sufficient to generate inflows that will see the dam storage rise by approximately five per cent of capacity in coming days," he said.
"This rain event has also resulted in some of the best tributary flows downstream of the dam, which means that towns and farms will be supplied by this naturally- occurring flow for some time without the need for releases from the dam as would otherwise be the case."
...the volume and frequency of rain events has been sufficient to generate inflows that will see the dam storage rise by approximately five per cent of capacity in coming days.WaterNSW spokesman
The worst drought on record left Burrendong Dam at less than 1.5 per cent of capacity at the start of this year.
But rain from mid-February alleviated the need for emergency measures aimed at keeping water flowing into communities like Dubbo.
A bulk water transfer from Windamere Dam to Burrendong Dam and the pumping of its remnant storage water have been put on hold.
"In all approximately 300GL of downstream tributary flow has been generated by rain events since February 2020," the WaterNSW spokesman said.
"Burrendong Dam was last at 30 per cent in mid-2018."
The turnaround has led Dubbo Regional Council to reduce water restrictions from level three to level one, as recommended by its chief executive officer (CEO) Michael McMahon.
His report to the council's monthly meeting on Monday confirmed the return of a 100 per cent town water allocation and the current cease-to-flow date.
"The NSW government's May 2020 assessment on cease-to-flow date for Burrendong Dam, based on zero inflows, has been moved to October 2021 by WaterNSW," he said.
Mr McMahon said the council continued to develop "capital projects, policies and best-practice to ensure there is no day zero" for the Dubbo region.
The capital projects include the yet-to-be-built cross-city pipeline which initially would move recycled water from the Dubbo Sewage Treatment Plant into the city to replace non-potable groundwater used for irrigation, and in turn take the groundwater to the John Gilbert Water Treatment Plant.