Cyclone Alfred: Lockyer Valley left up the creek again

Residents have been told to prepare for flood levels near the disaster experienced in 2011 as ex-Cyclone Alfred continues to reap havoc across southern Queensland.

Flooding in Laidley following Cyclone Alfred. Picture: Supplied

Residents of the Lockyer Valley, west of Brisbane, have been warned to prepare for fast-rising creeks to reach 2011 flood levels as the last breath of ex-Cyclone Alfred moves across Queensland’s southeast.

The emergency siren sounded in Grantham about 1pm on ­Monday after a blast of heavy rain from dangerous thunderstorms caused flash flooding through the low-lying township between Brisbane and Toowoomba.

The Lockyer Creek, which wraps the town, was expected to hit the major flood level of 13m on Monday, 14 years after the 2011 floods devastated Grantham.

Flood waters inundated several businesses in the neighbouring town of Laidley after water overflowed from the farming community’s namesake creek and flowed into the central business district.

Laidley Creek was expected to hit 8.85m on Monday, the peak height in January 2011.

The Lockyer Valley alert was one of four major flood warnings active through southeast Queensland on Monday evening, after Brisbane recorded its wettest day since 1974.

The Bremer River in Ipswich, southwest of Brisbane, was expected to hit March 2017 flood levels between 9pm and midnight on Monday, with residents along its banks warned to prepare to leave at a moment’s notice.

The area received rain ­totals in excess of 220mm through Sunday to 9am Monday, causing flooding at Rosewood and Walloon.

Gatton, in the Lockyer Valley, received 118mm rain in seven hours from 9am on Monday on top of 149mm on Sunday, the Bureau of Meteorology said, while west of Toowoomba recorded 99mm.

Several “watch and act” alerts were issued in Brisbane, including suburbs around the Oxley Creek and those downstream of the spilling Enoggera Dam.

Senior meteorologist Jonathan How said 100mm of rain could still fall overnight before conditions begin to ease into Tuesday.

“There is the risk of seeing some heavy showers and also storms,” Mr How said.

“Things will gradually start to ease off tonight back to showers. But the message is that flood risk is likely to continue, because we haven’t seen the peaks coming through just yet.”

At-risk homes throughout the Lockyer Valley were doorknocked by police last week and again on Sunday and Monday. Local deputy mayor Chris Wilson urged the community to stay vigilant.

“It’s been a long few days waiting for these events to come to us and now that it’s come, boy it has come in a big way,” Mr Wilson told the ABC.

The town of Grantham was moved to higher ground after the 2011 floods ­devastated the township when a three-metre wall of water rushed through the township, claiming 12 lives.

It has been three years since Grantham resident Caitlin Garton’s home went underwater in the 2022 floods, and the pregnant mum of two is hoping it won’t happen again.

“We are a little bit better prepared this time,” Ms Garton told The Australian.

“It is probably best it be a home than an evacuation centre with the two little people.

“Our plan is to hope it is not as bad; we haven’t had as much rain as last time.”

SEQWater confirmed water releases from the Somerset Dam had begun, but no plans were in place to release water from the Wivenhoe Dam until flooding in the Lockyer Valley and Ipswich receded.

The water agency’s chief executive, Emma Thomas, said 20 of the 23 ungated dams around the ­region were also spilling.

“It’s not just the water spilling, but also where else it’s flowing from into those catchments that creates different hazards,” Ms Thomas said.

“Enoggera is certainly very full, but we have seen it slowly declining in recent hours.

“That could change again if we get very heavy rainfall continuing in that catchment, so we’re watching that very closely.”

Mr How said widespread showers amounting to just 30mm to 50mm were to be expected on Tuesday, with the storms to push into the Darling Downs.

Ipswich under watch-and-act warning

Mayor of Ipswich Teresa Harding said the city was “on tenterhooks” for major flooding overnight into Tuesday.

Ipswich City, west of Brisbane, was under a watch-and-act warning for major flooding on Monday night as ex-Tropical Cyclone Alfred brought intense rainfall to the region.

Mayor Harding held grave concerns for Ipswich with river and creek rises already threatening residents.

“Obviously we had a major flood alert this morning, and we are on tenterhooks because we have been told we will have a major flood tonight,” she said.

Ms Harding expected the Bremer River, which runs through the city, to rise to at least 12.35m between Monday and Tuesday.

Major flooding in Ipswich occurs at any level above 11.7m.

In the 2011 floods which devastated Ipswich the Bremer River was at 19.4m, in the 2022 major flooding event the river rose to 16.7m.

Ms Harding is hoping the chance of flooding will be reduced because there were no planned releases of the Winvenhoe Dam, the key drinking water and flood mitigation dam for Brisbane.

Several releases of the Winvenhoe Dam contributed to the deadly flooding of the Bremer and Brisbane river in 2011.

There have been no controlled releases of the Winvenhoe Dam throughout the ex-TC Alfred event, with the dam’s flood mitigation compartment safely at 30% capacity before Alfred’s severe rainfall hit south east Queensland.

“Not having the Wivenhoe releases seems to be helping,” Ms Harding said.

Ms Harding warned that the worst could still be to come for Ipswich, as severe rainfall in the west threatens to run downstream to the city’s already saturated catchments.

Heavy rains and flash flooding pummelled the Lockyer Valley, west of Ipswich, on Monday.

Emergency workers were door knocking in Grantham in the Lockyer Valley, urging people to flee their homes on Sunday and Monday.

It is understood that homes in Grantham were beginning to flood by Monday night.

With Ipswich positioned 60km downstream from Grantham, alarms have been raised that major flooding could hit the city as early as Tuesday.