HOLEY MOLEY: Expert reveals cause of road collapse
A CRATER-like hole in a section of residential road remained cordoned off to people and traffic as experts determined it would take weeks to fix.
Noosa Council's infrastructure services director Carl Billingham today said this was the second time the area on Tingira Cres, Sunrise Beach had succumbed to a "washout", according to a geotechnical expert who had inspected the ground conditions.
Mr Billingham explained the erosion was believed to have happened after a blocked stormwater pipe burst beneath the surface during the weekend's deluge.
He estimated the hole was about 4m deep by 5m wide.
"We believe that a stormwater pipe was blocked and so the water banked up behind and then overflowed down the hill," Mr Billingham explained of yesterday's incident.
"It caused the embankment to slip, which took out the water main in there, and then that water main burst, and then that caused even more erosion underneath the road."
Mr Billingham said the area was "completely safe" and had been cordoned off to pedestrians and cars.
He said water had been cut off to the local area in the aftermath, but was now restored.
Power would likely to be reinstated to any affected properties later today, he said.
It will likely be weeks before the road is fixed, and Mr Billingham said the pipe would be diverted to avoid a future slip.
"At the moment we are clearing the trees out in the creek line, we have got a geotechnical engineer coming up with the solution for how we are going to solve the problem," Mr Billingham said.
"We have got specialist contractors coming in tomorrow morning, they will be stabilising that bank with ground anchors, once that is done Unity Water will come in and fix up the water main and then we will reinstate the road.
It will take a couple of days to stabilise the area and weeks before other works are finished.
Mr Billingham said there had been a number of similar "slip failures" in the past, including at the site and on the David Low Way, after sand had become saturated and given way.
Mr Billingham believed the heavy rainfall after a long period of dry weather had contributed to the situation.
"You either get blockages in the pipes, or what can happen is that the ground is so dry when it suddenly gets that load of water on top of it, the weight of it just causes it to slip," he said.