Engineer blames $30m speed sign project for Kuranda Range damage

A retired Cairns engineer is convinced construction of a hi-tech sign system contributed to spectacular destruction of the Kuranda Range Road, but TMR has dismissed those claims.

Landslides on the Kuranda Range Rd caused in the aftermath of Cyclone Jasper. Picture: Queensland Trucking

A Cairns engineer is convinced the installation of a $30m hi-tech sign system on the Kuranda Range Road contributed to landslides, but Transport and Main Roads has dismissed claims that drilling and vibration are to blame for undermining of the roadway.

First announced in January 2022 under the Cairns to Northern Tablelands Access Strategy, the Intelligent Transport System is a series of electronic road signs designed to minimise the risk of crashes on the range by reducing the speed limit on wet and foggy days.

Testing of the system began a week before the massive deluge brought by Cyclone Jasper and soon after huge sections the mountain fell down the hill taking sections of roadway with it.

Live testing of the Intelligent Transport System technology installed on the Kuranda Range began a week before Cyclone Jasper touched down. Picture: TMR

A German expatriate with a lifetime’s experience in road and railway projects, Wolfgang Rusch claims drilling to install the 18 ITS stations contributed to road damage that remains under repair.

“They had the drilling mob going for months on end and put lines through to service the signals,” the retired engineer said.

“Whenever you do drilling you create vibration, it loosens the ground, I guarantee in the next big shower more will collapse.

“They drilled either side of (the road) and drilled within a 1.5m of the existing bitumen.

“There’s nothing much underneath that and when you drill under the road to connect (junction boxes) up, that section where they drilled through is also undermined.”

Damage to the Kuranda Range Road showing ITS infrastructure. Picture: Queensland Police Service

Last year road crews installed 18 ITS units that required the digging of 150 electrical pits, installation of 31 poles for CCTV cameras and speed limit signs and 8km of electrical cabling between Smithfield and Rainforestation.

Images of the road damage have revealed exposed conduit and hardware associated with the ITS stations.

But TMR stated there was no evidence the Kuranda Range Road ITS infrastructure had increased the risk of landslips on Kuranda Range Road.

The Intelligent Transport System technology now installed on the Kuranda Range. Picture: TMR

Of the 150 electrical pits, two pairs of these pits were situated near a slip area and of 31 poles dug into the road shoulder, one of those was situated adjacent to a slip area, according to TMR.

Emergency night closures of the range between 9pm and 4am to allow for reconstruction of the road have now been extended until March 28 due to work progressing slower than expected.

Works were originally meant to be completed on March 15 but factors including wet weather, specialist material supply issues and challenging site conditions have meant works to rebuild the roadway including soil nailing and shotcreting (sprayed concrete) remain ongoing.

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Originally published as Engineer blames $30m speed sign project for Kuranda Range damage