Sumner Road from Evans Pass to Lyttelton has been closed since the February 2011 Earthquake, but repair work started in September to mitigate the geohazard risks around Crater Rim Bluffs at the top of road.
AS the first stage towards re-opening the vital link, work is being undertaken by McConnell Dowell, partnering with Beca, Doug Hood Mining and Geovert.
Works includes source rock deconstruction by scaling the upper reaches of the Crater Rims Bluffs, with a 400 metre long, 15 metre wide catch bench constructed at the base of the bluffs to protect the road below from rockfall.
A rock bund has also been constructed in Double Gully to the west of the Crater Rim Bluffs to capture rockfall from the bluffs. The bund will be several metres high and 50 metres long, and covered with basalt cobbles to reflect the basalt stone walls in the area.
To minimise environmental impacts and reduce cost, the existing road will now be used as a ‘haul road’ for transporting excess rock from the excavation of the bench, and structural repairs will be completed under the existing road. Using the existing road rather than constructing a separate haul road also makes a start on the repair work required to return the road to two-lane use.
After the geotechnical risk mitigation work is completed, the next stage of work will involve investigating the extent of the damage to retaining walls along the road. The road will then be repaired and reinstated. At this stage, it’s expected that the road will reopen in 2018.
The Sumner Road reopening project is jointly funded by the NZ Transport Agency, which is funding 83 percent of the project, and Christchurch City Council.
Sumner Road is recognised as a lifeline route for Christchurch, an economically important link between Lyttelton Port and the city, and a popular recreational space for tourists and locals.
Sumner Road is also one of four projects within the Sumner-Lyttelton Corridor programme, which aims to mitigate geohazard risks to road users and return the road corridor between the Sumner side of the causeway and Lyttelton to its pre-quake level of service.
Sumner Road is one of four projects within the Sumner-Lyttelton Corridor programme, and work on the other projects – Moa Bone Point, Wakefield Avenue and Shag Rock Reserve, is said to be progressing well.
If you are interested in receiving regular news subscribe to our monthly enewsletter here