Lifting seal creates pot holes on new highway

A defective seal is likely to create pot holes on about two kilometres of roadworks between Devon Hills and Perth – and a permanent fix will not come until spring.

This week the Department of State Growth confirmed road workers had identified a defective seal – the top layer of sprayed bitumen and aggregate – on the new Midland Highway.

In the defective section of road, the aggregate is coming off the bitumen, leading to the bitumen wearing down and pot holes forming.


A Department of State Growth spokeswoman said fixing the surface would require an additional layer of spray seal to be applied in October.

“Sealing requires warmer temperatures so that the bitumen remains hot enough for the aggregate to stick,” she said. 

“The contractor is currently monitoring the road surface and undertaking repairs on a daily basis, including sweeping of loose aggregate and pot-hole repair using asphalt, which can be used in colder weather.”

Despite the fault, the spokeswoman said Tasmanian taxpayers would not foot the bill for the fix.

“Normal contract management processes will ensure that the defective seal is rectified, and that the road meets the outcomes specified in the contract and is fit for purpose,” she said.

“There will be no additional cost to the taxpayer.”

While the road will remain open, the spokeswoman encouraged motorists to drive slower to reduce the risk of damage to the road.

“For their own safety and that of road workers, road users are reminded to comply with all posted speed limits, signs and directions,” she said.

The work is part of the $500 million plan over 10 years to upgrade 146 kilometres of the highway.