Channel plan to protect damaged Qld dam

Authorities will dig a bypass channel to keep water away from the damaged wall of a Queensland dam after fears of a collapse sparked an evacuation order.

Residents of Talgai were evacuated on Friday after water began spewing from a large hole in the wall of the Bolzan Quarry Dam, on the Southern Downs southwest of Brisbane.

Residents have since been allowed to return to all but one of the evacuated properties, after authorities determined it was safe to do so.

Southern Downs Mayor Tracy Dobie says safety is the top priority as work begins to shore up the dam.

"A bypass channel will be constructed around the southern edge of the dam wall to take the water away from the wall in a controlled manner," she's told ABC radio.

"That will be released down that valley, and that will contribute to the need for road closures, because there will be flooding."