Areas north of Adelaide, South Australia, were flooded after the Gawler and Wakefield rivers overflowed on 01 October, 2016. This is the second flood event in South Australia in the last two weeks. Further heavy rain is expected and warnings have been issued for flooding on the Torrens, Bremer and Upper and Middle Onkaparinga Rivers.
In New South Wales, the flood event that has been unfolding along the Lachlan River over recent weeks has forced further evacuations, this time in Condobolin and Wagga Wagga.
One man is missing in the floods and emergency teams have been carrying out search operations over the last 3 days.
The recent flooding in New South Wales is estimated to have caused AUS$500 worth of damage and wiped out wide areas of crops.
New South Wales
In New South Wales, the State Emergency Service (SES) said it has received 3,243 requests for assistance since the start of the flooding, including 115 flood rescues.
Over the weekend families in parts of Condobolin and Wagga Wagga were told to leave their homes or risk being caught in the floodwaters.
SES warned that the main flood peak on the Lachlan River is approaching Condoblin where the river is expected to exceed 7.2 metres on Wednesday, 05 October, 2016.
The evacuations over the weekend follow those carried out on 25 September in nearby Forbes, when the Lachlan River overflowed. The river peaked at 10.67 metres at the Forbes Iron Bridge during the evening of Sunday, 25 September.
Meanwhile, a man is still missing in the flood-hit Forbes area after he went missing on Friday 30 September at a lake near Burcher, southwest of Forbes. Search and rescue teams, including helicopters, have been looking for him for 3 days.
Wyangala Dam Release
Over recent weeks, the Wyangala Dam has played a central role in the flows of the Lachlan River and the communities that live along it.
At the start of June, the Wyangala Dam was at 38% of capacity. According to WaterNSW, levels then “rose rapidly from record-breaking winter inflows.”
WaterNSW therefore commenced on a series of flood mitigation pre-releases for Wyangala, beginning on 02 August, 2016.
Eryk Bagshaw at the Sydney Morning Herald explained, “Both the government and farmers had hoped that the water it had saved for months would be used for irrigation, but record September rain put an end to that. They had to open the floodgates.”
“The decision flooded properties from Wyalong to Forbes. No amount of warning could stop the damage unleashed by 35,000 mega litres being pumped through the saturated landscape. “
WaterNSW say that its management of the dam has minimised the impacts of the recent heavy rain on communities along the Lachlan. Chief Executive Officer David Harris said that in this latest rainfall event, WaterNSW stored more than half the peak inflows into Wyangala Dam, thereby reducing the peak flow at both Cowra and Forbes.
He added, “Our main concern during flood events is to reduce peak flows to minimise flood impacts to regional communities.”
“Only a fortnight ago, WaterNSW operated Wyangala to store all inflows until the downstream river peak had passed – meaning flood levels at both Cowra and Forbes were much less than would otherwise have been experienced.”
As of 03 October, the dam was at 96.7%, according to WaterNSW.
Parts of South Australia have endured days of severe weather, including storms, strong wins and heavy rain. As many as 1.7 million residents were left without power on Wednesday evening following severe storms.
Over the weekend 01 to 02 October, South Australia State Emergency Service (SES) issued evacuation orders for communities along the Gawler and Wakefield rivers.
The SES has supplied more than 250,000 sandbags since the heavy rains began. Communities have pulled together in helping each other build up temporary flood defences.
Some flooding was reported in the towns of Gawler, Virginia, Two Wells, Lewiston and Port Wakefield. Roads have been closed and homes damaged. Full damage assessments as still to be carried out.
— Matthew Pantelis (@MatthewPantelis) October 1, 2016
As of 03 October, South Australia SES said the threat of flooding had reduced around the Gawler and Wakefield rivers as levels began to stabilise. However, there is now an elevated risk of flooding in the Upper and Middle Onkaparinga River which may threaten Verdun, Lobethal, Oakbank, Woodside and Hahndorf.
SES have also warned of an elevated risk of flooding from the Torrens and Bremer Rivers and Langhorne Creek.
Australia’s Bureau of Meteorology has forecast further severe weather for the area, including strong winds and heavy rain.
Just 2 weeks ago around 80 homes were damaged and 75 families evacuated after record heavy rain in the Adelaide Hills area.
Aerial photos of Port Wakefield pic.twitter.com/NPEAG8E3fh
— SA SES (@SA_SES) October 2, 2016
— BOM Australia (@BOM_au) October 1, 2016
— DPTI South Australia (@DPTI_SA) October 2, 2016
This image is of Port Wakefield Highway at Virginia near Park road. pic.twitter.com/IZTdw29CmE
— SA SES (@SA_SES) October 2, 2016
It may drive like a boat but your 4WD doesnt belong in floodwater. About 80% flood deaths are men driving into floodwater & to a slow death. pic.twitter.com/vERSrExYX3
— NSW SES (@NSWSES) September 29, 2016
B - Condobolin
C - Wagga Wagga
Lachlan River, Forbes Iron Bridge - September 25 to September 25, 2016
During the major floods of August 1990, the river stood at 10.65
Forbes - September 24 to September 25, 2016
Condobolin - October 1, 2016
Wagga Wagga - October 1, 2016
Forbes - September 30, 2016