More work on Gap

The last major rock-falls at the Gap occurred in the first week of January this year.

The latest phase of traffic delays through Cunningham’s Gap commenced this week and are expected to continue through until the second week of December.

The Queensland Department of Transport and Main Roads (TMR) says the delays are due to “survey work” being undertaken on the roadway at the Gap ahead of a “reconstruction project”, design for which is expected to be completed in 2021.

But the department is remaining tight-lipped about the full extent of reconstruction works needed at the Gap despite questions from the Free Times, saying “design” of the project is expected to be completed in 2021.

What is known at this point in time is that more delays are expected next year when extensive removal of unstable sections of the cliff face above the highway is expected to be carried out, potentially similar to blasting works which happened way back in 2010 to remove large areas of rock.

Calls continue for a permanent solution for the highway through the Gap – which has been closed on repeated occasions due to rock-falls over the last decade and a half – but to date options such as a tunnel through the mountain or a concrete ‘cover’ over the highway remain off the table.

The road closures have come at significant disruption and cost to the region’s freight operators, and to domestic travel, with the highway the prime connecting route between the Southern Downs and Granite Belt regions and the metropolitan corner of South East Queensland.

On Monday of this week TMR introduced “temporary restrictions” at Cunningham’s Gap, which a spokesman told the Free Times would “allow for investigation and survey works related to major future upgrades of the highway.”

“Day-time restrictions will be in place between 9am and 3pm until (tomorrow) Friday, 13 November, 2020,” a spokesman told the Free Times.

“Night restrictions will be in place between 6pm and 6am from Monday, 23 November, until Thursday, 10 December, 2020.”

The spokesman said ongoing delays are likely to include –

• Possible delays between 45-60 minutes

• Vehicles will be stopped at the top and bottom of Cunninghams Gap and escorted through by a pilot vehicle

• Travel will be reduced to a single lane only with stop/slow traffic conditions

• The speed limit will be reduced to 40km/h

In addition the following restrictions will apply to “oversize” vehicles –

• Oversize loads wider than 3.5m (ground contact width) and 4m (load) will not be permitted through the site between 6am and 6pm

• Oversize loads wider than 4m (ground contact width) and 7m (load) will not be permitted through the site at any time

“We have notified the trucking industry and other key stakeholders of traffic changes to enable them to plan their travel in advance,” the TMR spokesman said.

“Additionally, permanent variable message signs will be installed at various locations along Cunningham Highway in 2021.

“Electrical works for these signs are underway this month (November) around Warwick and Aratula.

“Motorists can expect some reduced speed limits around these works and are asked to drive to the traffic conditions and obey all signage.

“Weather, site and contractor conditions can impact works, delaying start and finish schedules.

“We appreciate motorist patience while these important works are carried out.

“For the latest information on road closures and traffic conditions across Queensland, visit www.qldtraffic.qld.gov.au, download the QLDTraffic app or phone 13 19 40 for further assistance.”

(SUBHEAD)

Scant details?

The Free Times this week asked TMR to provide more information on what is has termed the ‘Cunningham’s Gap Reconstruction Project’, and received the following response, which it must be noted does not include specific timeframes for any works planned for 2021…

“We have started the design phase of the Cunninghams Gap reconstruction project, including the ground investigations,” the spokesman said.

“The outcomes of these investigations will help determine the best way to repair the damage.

“This is an incredibly complex project which requires challenging geotechnical investigations in extremely rugged terrain, including cliff faces.

“TMR is expected to complete the design phase next year while continuing to work with the independent technical reviewer to ensure the most suitable engineering solution and best value for money for taxpayers is identified.

“Construction will follow once the design is complete.

“The project will repair fire-related damage in this area.

“The investigations for the reconstruction works are about the last 1.8km of Cunninghams Gap, leading to the monument at the crest of the slope.

“Minor reconstruction works outside of this area are also likely.

“The removal of boulders is being investigated and further geotechnical investigation will be required.

“Previous experience with slopes of this complexity, and level of fire damage, suggests scaling of slopes and dislodging boulders may be necessary in some areas.

“It is expected geotechnical controls will likely be a necessary feature of this reconstruction project with further design work required to identify the details and locations.

“Further information will be provided to the community once the design is finalised and the reconstruction work details, timing and locations are known.

“Eligible reconstruction works are jointly funded by the federal and Queensland Governments under the Disaster Recovery Funding Arrangements (DRFA).”

Updates on likely required works at the Gap have been sought for most of 2020, since the Gap was closed for lengthy periods in late 2019 and early 2020 due to bushfires and to a lesser extent rainfall, both of which caused disturbance and subsidence on the cliff face.

The State Government conducted large-scale stabilisation works at a cost of nearly $60 million over a two-year period concluding in late 2012, after a series of highway closures from 2005 to 2010 due to land slips both above the highway and beneath it.

Those land slips were caused and hampered by heavy rain at various times leading to major engineering studies and a series of heavy works including the blasting out of a 23 tonne boulder in May 2010.

Concrete barriers and shipping containers on the western side of the highway through the Gap have since formed a line of defence against further land slips.

A boulder along with soil, rock and debris all weighing an estimated 20 tonnes fell to the base of the cliff in the first week of 2020, attributed by TMR to the bushfires.

A TMR spokesman at the time said the assessments carried out as a result “identified long-term slope stability rectification works requiring complex design solutions, possible permanent road protection and restoration works”.

The State Government has previously looked at the options of a tunnel through the Main Range, a concrete structure over the highway and an alternative route through Spicers Gap as long-term options to ensure the reliability of the Cunningham Highway through the Gap.

In January of this year TMR said “safety mitigation measures” in the first week of 2020 “were activated at known high-risk areas enabling the highway to reopen, including a portable steel safety barrier inside the permanent concrete barrier”.

“Additionally, the speed limit was reduced to 50km/h and traffic controllers were on site for over a week continuing to monitor the situation,” the department said at the time.

“On-going inspections continue to be undertaken on-site.”

(BREAKOUT)

Federal MP for Maranoa – and Federal Agriculture, Drought and Emergency Management Minister – David Littleproud slammed the Queensland Government in late October for what he said was its “failure to commence repairs at Cunninghams Gap following the Black Summer Bushfires”.

“Almost a year since fires swept through the area, Southern Downs communities have no certainty as to when reconstruction works will begin because they haven’t even completed the planning of the engineering solution,” Mr Littleproud said.

“Road users are still being forced to use a single southbound lane, and regularly experience delays due to very slow heavy vehicle traffic.

“This is expected cost in excess of $200 million which the Federal Government will fund up to 75%.

“It is inexcusable for the Queensland Government to sit on their hands.

“It’s not just citizens in Maranoa that are impacted.

“This is a major freight route between Brisbane and Sydney.

“The clock is ticking and our regions west of the Great Dividing Range that rely on this major road can ill-afford the ongoing bottlenecks to continue indefinitely.”