Rock stabilisation Nevis Bluff, Queenstown Lakes District
16 September 2019
Rock stabilisation Nevis Bluff, Queenstown Lakes District, late September to mid-December
People who use the road between Cromwell and Queenstown, State Highway 6, will see abseilers and drilling activities at the Nevis Bluff from Monday, 23 September.
The NZ Transport Agency’s Aspiring Highways team is about to start significant further rock stabilisation work at the Bluff.
Drivers travelling between Cromwell and Queenstown are reminded to take extra care around any road crews or traffic management sites. Short delays are possible.
“As part of the Transport Agency’s ongoing safety and monitoring of the Nevis Bluff, this planned work was put off in earlier 2019 to stabilise a more unstable area of the Bluff. This was completed in early July,” says Mark Stewart, Central Otago Maintenance Contract Manager, NZ Transport Agency.
The planned stabilisation of the rock mass known as ‘Midstream Columns’ (see map below) provides a number of benefits for the long-term management of the Bluff and road users’ safety:
Stabilising a large section of the rock face
that was undermined with the road widening in the early
1970s, which will
Secure an access bench that provides good and easy access to the upper reaches of the Bluff, and
Provide a key location for the installation of future rock fall protection measures for the Nevis Bluff.
“The cost of the work, which will take around 12 weeks to complete, through to mid-December, is around $850,000,” says Mr Stewart.
“The work will involve stabilising the rock mass with around 130 rock bolts. The rock mass is a key part of the Bluff and it would be significantly disruptive to road users to blast using explosives, although some small blasting will occur in the first two to three weeks to clean up the rock face,” he says.
“Most of the work can be completed with the road remaining open to two lanes with minimal disruption to road users.”
The Midstream Columns rock feature is next to the site of the 30,000 cubic metre Nevis Bluff 1975 rockfall, which closed the road for several weeks and caused significant disruption for months afterwards while clean up and stabilisation work was completed.