Currently 100 per cent of NSW has been declared in drought, and with well below average rainfall, dam levels have dropped significantly during the past 12 months.

WaterNSW data provided to Fairfax Media show that every dam it manages across the region has dropped significantly during the past 12 months.

Burrendong Dam may be one of the largest inland dams in the state, and three times the size of Sydney Harbour, but in the past 12 months its capacity has dropped from 81 per cent to 31 per cent.

This drop is the equivalent of 581 gigalitres (581,000 megalitres) less water than a year ago.

Burrendong Dam is the water source for residents and businesses in Dubbo, Wellington and Narromine. Water restrictions are in place for Narromine.

Carcoar Dam, which supplies water to Blayney, has also had a significant drop in its capacity during the past 12 months – from 91 per cent full in September last year to 67 per cent full this month.

This 24 per cent decline means there is now nine gigalitres less available water.

While the water level at Wyangala and Oberon dams have both dropped by 31 per cent compared to a year ago, from 88 per cent to 57, and 85 per cent to 54 respectively.

Water restrictions are in place in Forbes and Parkes which both use water from Wyangala Dam.

Burrinjuck Dam has also dropped – from 59 per cent capacity to 41 per cent during the past year, while Windamere has fallen from 49 per cent to 40.

Meanwhile, the Lithgow City Council run Farmers Creek Dam is at 100 per cent capacity and a council spokesperson said the dam is supplemented by treated mine water which is pumped in from the Clarence Colliery.

Chifley Dam, run by Bathurst Regional Council, has dropped from 89.8 per cent to 58.9 in the past year.

A council spokeswoman said that with recent rainfall in the catchment, the dam level had increased by six per cent in the past few weeks.

“Council will continue to monitor levels closely and encourages residents to be waterwise throughout the year, irrespective of dam level,” she said.

The water supply in Orange comes from two dams – Suma Park and Spring Creek.

Currently, the water level in the dams is 47.1 per cent and 81.0 respectively, which is down compared to one year ago when it was 75.9 per cent and 94.2.

Orange City Council corporate and community relations manager Nick Redmond said the stormwater harvesting holding dam was at 97 per cent capacity, with a full capacity of around 220ML.

“It’s currently pumping about 6.5ML a day into Suma Park Dam. Coupled with the Macquarie Pipeline, we’re pumping about 18ML per day into the dam in total,” he said.

“The amount taken out of the dam to service the city’s water supply needs is about 12 ML per day.”

Mr Redmond said council’s modelling showed the city should be able to remain on level two water restrictions for the rest of the year.

“If the water level drops below 50 per cent the policy is Orange would go to level three water restrictions, however it isn’t likely to happen soon,” he said.

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