Warragamba Dam spill peaks but more rain forecast

Warragamba Dam spill peaks but more rain forecast

22 March 2021

The volume of water spilling from Warragamba dam is currently 300 gigalitres per day (GL/day), after falling from an overnight peak of 500 GL/day.

This is down from yesterday’s initial spill rate of 450 GL/day yesterday (Sunday, 21 March) as days of heavy rain across the catchment continue to generate large inflows into the dam.

With more rain forecast by the Bureau of Meteorology in coming days, the likelihood is that the spill rate could rise to a second peak, possibly midweek.

Other Sydney supply dams are also receiving inflows, with Nepean, Cataract, Cordeaux and Avon dams all spilling.

On current forecasts it is likely Warragamba will spill for at least another week and thereafter lower volume inflows into the dam storage could continue for some time.

Modelling indicates that approximately 1500 GL of water will flow into the dam in the seven days since the extreme weather event commenced, a figure that represents 75% of the dam’s storage capacity of 2000 GL.

WaterNSW is maintaining a dedicated 24-hour incident management team that is working closely with the Bureau and the NSW State Emergency Service to monitor weather and dam inflows.

WaterNSW will continue to work closely with Sydney Water and NSW Health throughout the rain event, to watch for potential water quality impacts on untreated supply.

For weather forecasts and flood warnings visit http://www.bom.gov.au/

For emergency information visit https://www.ses.nsw.gov.au/ or contact 132 500

For information on WaterNSW dams visit www.waternsw.com.au or contact 1300 662 077

Media contact – Tony Webber - 0428613478


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