Wastewater Network Restoration Following the Canterbury, NZ Earthquake Sequence: Turning Post-Earthquake Recovery into Resilience Enhancement

The Canterbury earthquake sequence, 2010-2011, seriously impaired the wastewater network across much of the Canterbury region, New Zealand, by both seismic shock and liquefaction impact. This paper provides a preliminary overview of how infrastructure resilience is highlighted and built into rehabilitation practices and decision-making processes adopted by asset owners to reinstate the wastewater system in Christchurch. The physical damage suffered by the Christchurch wastewater system is briefly presented. Secondly, the decision-making processes for reconstructing the affected sewer system conducted by rebuild delivery agency - Stronger Christchurch Infrastructure Rebuild Team (SCIRT) as agreed by its clients: Christchurch City Council (CCC), Canterbury Earthquake Recovery Authority (CERA) and New Zealand Transport Agency (NZTA) are discussed with particular attention to the aims of achieving and enhancing infrastructure resilience. Furthermore, the paper describes how local and international experts have engaged with SCIRT, CCC and CERA to provide know-how in support of development of new Infrastructure Technical Standards and Guidelines that will underpin new design and construction of wastewater systems, describing the decision-making process that has resulted in the resilient rehabilitation of the Christchurch wastewater network.