Asset assessment using GIS and Infonet

Throughout the past 23 months, Christchurch City has encountered four significant earthquakes (EQ) of magnitude 6 and above. The earthquake of 22 February 2011 centred 2km West of Lyttelton and 10km southeast of the centre of Christchurch, w hich follow ed five months after a magnitude 7.1 earthquake in September 2010, tragically took 185 lives. It caused w idespread damage across the central city and neighbouring eastern suburbs, exacerbated by buildings and infrastructure already weakened from the September 2010 event and subsequent aftershocks. It is estimated that the total cost to insurers of rebuilding the city w ill be approximately NZ$15 – 16 billion.

Follow ing the February quake, significant liquefaction affected the eastern suburbs, producing some 400,000 tonnes of silt which mixed with wastewater to become a significant health risk. Wastew ater and sewerage systems were severely damaged with households having to establish emergency latrines. More than 20,000 chemical toilets w ere distributed around Christchurch together w ill some 2,000 portable toilets. A significant portion of the ground level in the eastern suburbs has dropped, resulting in varying levels of flood risks during w et w eather. This, coupled w ith severely damaged stormw ater infrastructure, has added to the issues in the eastern suburbs.

This paper explores how Christchurch is embarking on rebuilding the w astewater and stormw ater infrastructure, and the integral role that thorough data assessment, using GIS and InfoNet is playing in this strategy to ensure that multiple data sources are reviewed, risk profiled and then prioritised to meet the requirements of the Stronger Christchurch Infrastructure Rebuild Team, insurance companies and the future asset management processes of Christchurch City Council.