Rebuilding the foundations of a city

Overview

Following the Canterbury earthquake sequence, Christchurch faced one of the largest infrastructure programmes undertaken in New Zealand. Roads, bridges, wastewater networks, stormwater systems, retaining structures and community assets required extensive repair, renewal, or reconstruction.

Downer is proud to have been one of five construction companies in the Stronger Christchurch Infrastructure Rebuild Team (SCIRT) alliance. Working alongside Christchurch City Council, the Canterbury Earthquake Recovery Authority and the New Zealand Transport Agency, Downer contributed engineering expertise, construction capability and experienced delivery teams to restore the horizontal infrastructure on which the city depended.

The challenge

Damage extended across densely populated neighbourhoods, central-city streets, and essential underground networks. The recovery programme coordinated hundreds of projects while Christchurch began recovery and rebuilt the day-to-day operations of a main centre, requiring careful staging, traffic management, stakeholder engagement and close integration between designers, asset owners, utility providers and delivery teams.

The evolving scope also demanded a delivery model that could respond quickly to new information, balance funding and service-level decisions, and maintain a continuous pipeline of work across the city.

Downer’s contribution

Downer’s dedicated SCIRT delivery team planned and delivered repairs and reconstruction across transport and three-waters infrastructure. Our teams worked in an integrated environment that combined design, estimating, risk management, construction planning and delivery, enabling solutions to be developed collaboratively and applied across the entire programme.

Downer supported shared learning and continuous improvement across SCIRT. Within the unique alliance model applied, where both competition and collaboration was used to drive performance, Downer successfully achieved delivered cost effective and high-quality outcomes with safety and community centred.

Programme outcomes at a glance

Programme investment	$2.2 billion
Programme duration	Five and a half years
Individual projects	700+
Wastewater pipe repaired	560 km
Stormwater pipe repaired	56 km
Freshwater pipe repaired	97 km
Roading completed	1,384,236 m²

Project spotlight: Bridge of Remembrance and Triumphal Arch

Downer led the repairs to the Bridge of Remembrance and Triumphal Arch, a Category 1 heritage landmark in central Christchurch, and one that holds significant and symbolic meaning to people in Christchurch and beyond. The sensitive project was delivered from April 2013 to September 2015.

The completed works strengthened the structures to a 1-in-2,500-year earthquake-event rating. The Triumphal Arch saw 32 new 300 mm micro-piles installed to depths of 28 metres, reinforced concrete pile caps, structural steel columns and beams, rocking collars, sliding joints and post-tensioning.

The repairs strengthened a Christchurch landmark, in the face of genuine adversity.

Outcome and lasting impact

SCIRT restored essential infrastructure needed for residents, businesses and public services to move towards normality after the earthquakes. The Office of the Auditor-General reported that the alliance agreement contributed to the effective and efficient rebuild of horizontal infrastructure and that delivery teams had delivered work under budget as of its 2016 follow-up audit.

Downer’s contribution combined local delivery capability with engineering and construction expertise across a complex, city-wide recovery environment. Its work on projects such as the Bridge of Remembrance demonstrates how resilient infrastructure delivery could be combined with the careful restoration of places carrying deep community and cultural significance.