Waka Kotahi NZ Transport Agency will be closing SH73, the Arthur’s Pass route linking the West Coast and Canterbury early in December for around two weeks. The closures will affect daytimes on weekdays, 10 am to 6 pm, Monday* 4 December to Friday 15 December.
(*Please note: Due to poor weather forecast the start date has shifted to Tuesday, 5 December. This will be confirmed on Monday, 4 December)
“Drivers will be able to use SH73 between Otira and Arthur’s Pass village up to 10 am each day and after 6 pm at night, Monday to Friday,” says Mark Pinner, Canterbury/West Coast System Manager, Waka Kotahi.
“We know this closure will be unwelcome for many regular road users, businesses along the route and visitors to the West Coast, but this fortnight before the Christmas holidays has the least impact overall, compared to later options, and follows extensive engagement with travel, hospitality and freight operators,” says Mr Pinner.
“Our aim is to ensure that the highway remains safe and fit for purpose for many years to come,” says Mr Pinner. “We want to reduce the potential for more frequent short-term delays in the future due to failures in the road surface. It is now starting to crumble in places. This road is constantly under significant stresses from its grade (16%) and the alpine environment with seasonal weather extremes,” says Mr Pinner.
Around 1500 vehicles a day use SH73 on average.
“This will be inconvenient for many people, but we believe this is the shortest and most efficient way to get this key piece of work, both sides of the highway, completed safely and successfully. We thank everyone for building in the extra hour if they need to take the SH7 Lewis Pass route during this time, or if they organise their trip around the closures times. People travelling from Hokitika need to build in an extra hour-and-a-half for the Lewis Pass trip.”
Around 342 metres of SH73 above the Rock Shelter below the viaduct on the Otira/West Coast side of the highway needs to be re-surfaced with new asphalt. It was last fully resealed around 12 years ago, with just short-term repairs in more recent years.
The road is narrow in this part of the Otira Gorge – around 7.5 metres guardrail to cliff face on the inside across two lanes. This means the paving and sealing machines fill up the space and do not allow room for traffic to safely pass while work is underway, says Mr Pinner.
The lack of safe working space for the paving crew can be seen in this cross section under the Reid Falls chute, hence the need for the full closure to traffic while this work is underway:
Waka Kotahi consulted on a range of opening times and durations. Stopping the crews and machinery to enable a midday traffic convoy would reduce productivity significantly and more than double the length of time required to do this work, says Mr Pinner. “The people we have spoken to agreed that a shorter timeframe with a more productive working day was preferable to a longer period of time – potentially running right into Christmas or the New Year.”
Waka Kotahi has to keep the teams doing this work safe while they’re on site and the rockfall risk cannot safely be managed at night when it can’t be seen.
The asphalt surface being constructed needs a minimum air temperature, which we only get during the warm, summer months. The work is also weather dependent. “If the crew can’t work due to bad weather, the road will remain open on those days, but it may result in those days being rescheduled for a later date,” says Mr Pinner.
Distances/ times comparison Arthur’s Pass/Otira versus Lewis Pass, advice for travellers to get to the road block in time: