Sydney rainfall to boost metro storage levels

Sydney rainfall to boost metro storage levels

29 November 2018

Sydney’s dam storage total could rise by up to 1.5% as a result of yesterday’s significant rain event.

Though rainfall totals in the catchment did not match those in the city, they generated inflows that will continue for some days, potentially adding up to a month of supply to Sydney’s drinking water storages.

Sydney’s total dam storage, which started the week at 60.3% of total capacity, is already at 61.3 and could reach 61.5% by early December.

Even with a return to dry conditions, Sydney’s storages are unlikely to hit 60% until late December.

Inflows into Warragamba Dam peaked at a rate of 6 gigalitres/day overnight, and dams such as Nepean, Avon, Cataract, and Cordeaux also experienced inflows.

Tallowa Dam started spilling overnight, and as a result transfers from the Shoalhaven system were ramped up, in a further boost to Sydney’s water security.

Inflows could have been higher had heavy rain forecast for yesterday afternoon eventuated, WaterNSW CEO David Harris said.

“While we are mindful of the harm caused by the storm, the welcome benefit to Sydney’s water security situation cannot be overlooked.

“In addition to the inflows generated, this rain event has also saturated much of the catchment, raising the likelihood that any follow-up rain will result in us harvesting more water for the people of Sydney.

“This has been the best rainfall we have received across Sydney’s drinking water catchments since March 2017 when Sydney storages were at 96%. It is a welcome break from the dry conditions that we have experienced over the last 18 months,” he said.

“Our water quality experts are monitoring storage inflows to ensure there is no adverse impact on water quality as a result of this replenishment of Sydney’s drinking water storages.”

Media Contact – Tony Webber – 0428 613 478


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