top of page



Dec 2023 – Current


Christchurch City Council 


Christchurch City Council 



An earthquake damaged retaining wall supporting a Lyttelton Street required rebuilding to enable the removal of the temporary concrete support blocks and reinstatement of the footpath on top of the wall. Prior to the retaining wall works commencing an overhead power service needed to be relocated underground to enable piling equipment to complete the pile hole excavation safely.

The lower section of the wall has been constructed from within the private property of 1 Bridle Path, the remaining upper section will be constructed from the road corridor. A temporary works platform has been constructed above the wall to avoid surcharge loading the road while the remainder of the post-earthquake retaining structure is removed. This temporary works platform is a critical health and safety component of the project to prevent further damage to the road or more seriously a slope failure.  

The new wall construction has steel piles cast in concrete 6-8m below ground level and a retained height of 2-4m. The retained section has timber lagging set between the steel piles, and a reinforced concrete capping beam atop. Hunter Civil completed the auguring of the 13 pile holes inhouse using a 13.5T excavator with a boom mounted auger attachment.

To help ensure the safety of the work crew the backfill behind the completed wall will be ‘no fines concrete’, as this product does not require the use of a plate compactor or person in the gap between the new wall and the cut slope of earth. Finishing works include reinstating the footpath to its pre-earthquake alignment, installing a steel handrail and mesh fence, and removing all temporary works and house protection measures.

Given the close proximity of the occupied private property to the new retaining wall Hunter Civil had to undertake regular communication with the tenants to ensure that they were aware of the works we were completing and when. We also undertook specific measures to ensure the protection of their property and to provide them with some privacy from our work area. Positive feedback has been received to date regarding our excellent communication and works.

bottom of page