Brisbane floods ‘not expected’ as Wivenhoe dam opens the gates

Water will slowly be released from Wivenhoe Dam in a move managers insist will not cause flooding downstream.

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Water will slowly and strategically be released from Brisbane’s main drinking water supply – Wivenhoe Dam – for four days in the wake of Cyclone Alfred, in a move managers insist will not cause flooding downstream.

As the rain slowed and the flood risk eased in southeast Queensland and northern NSW, more than 91,000 homes and businesses were still without electricity, and thousands had no mobile phone, internet or landline service. At the height of the out­ages, 450,000 properties in Queensland had no electricity.

Frustration on Tuesday saw Logan mayor Jon Raven demand telecommunications companies “pull their finger out” and shift generators to his fast-growing city just south of Brisbane, where an estimated 30,000 people had been without phones and internet for days.

Mr Raven said Telstra and Optus had boasted in pre-cyclone Queensland disaster management committee meetings – chaired by Premier David Crisafulli – that they had plenty of generators and battery back-ups ready for when Alfred inevitably cut power to telephone towers. But he said Logan seemed to have been forgotten.

Dominic Porter from Hassard Industries in the aftermath from flooding caused by ex-Tropical Cyclone Alfred in Bundamba, on Tuesday. Picture: Tara Croser.

People were unable to run their businesses without access to phones and mobile data, and they could not call Triple 0 or get emergency text alerts warning to evacuate because of flash flooding.

“It’s really frustrating for people … they’re like ‘we can charge our batteries and our phones at the recovery centres, but if we go home and a text message comes through saying evacuate now or watch out for floodwater’ they don’t get those messages because there’s no reception. And they can’t call Triple 0,” he said.

He said after he challenged the telcos on Tuesday, Optus moved generators to several Logan phone towers, giving residents the ability to make emergency calls but not use mobile data.

An Optus spokeswoman said the telco had 39 sites in the Logan area which stayed connected through the cyclone. Twenty-nine had been restored, and it was working to fix remaining sites. One generator was sent to Logan before the cyclone, nine more were deployed when the bad weather started, and two more were sent on Tuesday.

“Emergency calls to Triple 0 on mobile networks during power failures should work if at least one telco carrier is available,” she said. “In the event no carrier is operational at times when there is no power, Triple 0 calls will not connect … and SMS messages are not able to be received by customers of any telco providers in that area.”

On Tuesday afternoon, there were still 15 blackspots in the region hit by the disaster, including parts of the Gold Coast, Sunshine Coast, Moreton Bay and the bay islands, Tamborine Mountain, and inner-Brisbane.

Vodafone still had 136 mobile towers down in Queensland and 12 out in NSW due to power failures, and about 147,000 properties had lost connection to the NBN. For Telstra, 68 mobile towers, 5578 landline phone services and 1587 ADSL internet services were out of action.

An aerial view of Wivenhoe Dam at 86.3pc ahead of Cyclone Alfred. Picture: Peter Wallis

Meanwhile, SEQ Water chief executive Emma Thomas confirmed water would start to be released from Wivenhoe Dam on Tuesday night, for the first time during the natural disaster, to ensure the dam level was low enough to cope with any future heavy rain.

Ms Thomas said the releases would be slow and steady, and would not start until other creeks and rivers had subsided, to ensure the Brisbane River stayed below the minor flood level.

“We’ll wait until the river peaks and recedes, before we release anything from the Wivenhoe Dam,” Ms Thomas said.

“I don’t expect the releases we’re making to cause flooding in the lower Brisbane River.”

Of the region’s 23 ungated dams, 20 are overflowing. Gated releases are also occurring at North Pine and Somerset dams.

The clean up after Alfred at Currumbin on the Gold Coast. Picture: Adam Head

On the Gold Coast, mayor Tom Tate – who was overseas on holidays for most of the cyclone response – said he was confident the city would be ready to welcome tourists back for the Easter holidays “so that we don’t face economic disaster as a result of Alfred”.

He said the damage to beaches was mostly on the coast’s northern end – where Main Beach at Surfers Paradise beaches had been ­almost wiped out by erosion – but the southern end between Broadbeach and Coolangatta had fared better.