Waimakariri Bluffs rockfall risk reduction work coming up, SH73

2 MinutesBy NZ Trucking magazineSeptember 12, 2019

The NZ Transport Agency is advising road users on State Highway 73, between the West Coast and Canterbury, to anticipate short delays from next week as a second part of the highway goes down to one lane for safety work.

“Drivers will need to build in extra time on this route to the end of the year,” says NZTA portfolio manager Colin MacKay.

Slope stabilisation at the Waimakariri Bluffs, on the Canterbury side of the river, west of the Mt White bridge turnoff, will involve abseilers removing loose rocks, drilling rock anchors and placing rockfall netting on the cliffs.  Work will start on Monday, 16 September and will run through to December at least.

It is weather dependent, given the heights abseilers will be operating at.

“Work will be underway on weekdays, Monday to Friday, 7am to 7pm and will reduce the highway to one lane alongside the bluffs for around 800 metres. In the first few weeks, when rocks are being removed from the cliffs and there is the potential for blasting to be used, drivers may have delays up to 50 minutes,” says MacKay.

“Most of the time in the early stages, the delays will not be for that long.”

For the second stage of work, from late September to October, rock anchors will be drilled in place and by November, rockfall netting will be attached. Traffic signals will control single lane traffic along the highway and crews will be aiming for minimal delays.

“We appreciate that due to the recent fire at Porters Pass, there is already an area with 10-minute delays to the west on this key state highway where guardrail is being replaced,” says MacKay. “However, we understand the crews on Porters Pass are working hard to keep delays to a minimum and that repair work should be completed by early October.”