Residents return to homes after Bolzan Quarry Dam leak

Most of the residents evacuated from areas around a leaking dam in Queensland’s south were allowed to return home on Sunday afternoon.

The Bolzan Quarry dam wall has continued to collapse.

Most of the residents evacuated from areas around a leaking dam in Queensland’s south were allowed to return home on Sunday afternoon, with repair works set to begin amid warnings that the structure was still in serious danger of collapse.

Residents of six properties evacuated near the Bolzan Quarry Dam at Talgai, north of Warwick, went back to their homes on Sunday after new modelling showed they would not be impacted if the damaged wall collapsed. One nearby home directly downstream from the dam remained vacant.

Southern Downs Regional Council issued an emergency warning on Friday evening after a local discovered a 3.5m hole in the wall of the privately-owned 433-megalitre dam. The hole subsequently grew almost 5 metres in size, resulting in water gushing from the dam and water levels dropping significantly.

Local mayor Tracy Dobie said there is still a real chance the wall could fail in the coming days.

“The dam wall is unstable. Flood modelling done today shows the dam would create half of a 100 year flood,” Cr Dobie told The Australian on Sunday evening.

“Water is moving fast but dam levels are dropping slowly.”

Construction of a bypass channel will begin on Monday morning to remove water and take the pressure off the damaged wall, which is expected to take a day to complete.

Remediation on the hole in the wall cannot take place until dam levels are lower.

The Southern Downs Regional Council issued an emergency warning on Friday over the breach in the 433-megalitre dam, which remains in place. The size of the hole is reportedly now approaching 5m in size.

“Engineers are still not able to declare the wall safe,” said local councillor Cameron Gow on Sunday.

“The hole has collapsed a little bit more.”

An evacuation order remains in place.

The council on Sunday said the flow of water from the dam is controlled, although concerns still remain over the cause of the wall’s failure.

“Residents are advised to please remain out of the area until Queensland Police advise the PSPA (Public Service Preservation Act) is lifted,” the council said in a statement.

It’s understood the prolonged drought may have caused the dam’s clay liner to dry out and crack leading to a breach in the wall.

A smaller dam with a 50-megalitre capacity below the main agricultural dam and a large paddock would contain some overflow should the dam burst.

Despite the outflows, the dam remains at 75 per cent capacity after a deluge of rain last weekend hit the state.

Elsewhere, flood conditions are continuing to ease.

However, the Bureau of Meteorology says communities around the southern interior should remain cautious of flooding over the coming days.

Major flood warnings are in place for the Georgina River, lower Condamine River and upper Balonne River.

On the Gold Coast, police are still searching for Yang Chen, 26, who disappeared in the hinterland area while walking near Gorge Falls in the Tallebudgera Valley earlier this week.

With AAP