River rises to allow pipeline's first spin

FEARS the Macquarie Pipeline could become a white elephant were extinguished this week when the pipeline started making its first major contributions to Orange’s water supply reserves.

After a number of commissioning tests, the 39-kilometre pipeline was turned on for the first time on Wednesday night.

Pumps will be operated at night to take advantage of lower electricity costs.

Mayor Reg Kidd said the pipeline had not been used since its 2015 completion because Suma Park was at capacity until December last year.

“It’s been gradually declining since then,” he said.

“Last week Suma Park was at just over 70 per cent of capacity.”

While the pipeline can be used when Suma Park dips below 90 per cent and the river is flowing faster than 108 megalitres a day, the equivalent of 43 Olympic swimming pools, staff also take into account water storage levels, long-term weather forecasts and current water use to predict future water storage needs.

The river at Long Point has been above the threshold for all but one day since the start of December due to heavy rain, running as fast as 506 megalitres a day on Friday. 

The pipeline is currently contributing the highest daily volume of water into the dam, at 13.4 megalitres a day, with pumps operating nine hours a day.

Stormwater harvesting is next highest at 8.6 megalitres a day, with pumps operating around the clock.  

Normal inflows from the catchment are currently at 8.2 megalitres a day, while underground bores at Clifton Grove and Orange Showground are contributing 0.9 megalitres a day, with pumps operating 12 hours a day.

The total added water is about 30 megalitres a day, with the community using 15.

Orange City Council infrastructure committee chair and councillor Sam Romano said the aim was to keep overall water storage levels at about 80 per cent capacity.

“The aim is that by pumping during periods of good flow in the river, Suma Park dam will be topped up.”