Research into combined impacts on lifeline systems
UC researchers and students investigating combined impacts on lifeline systems
September 30, 2013
Two University of Canterbury (UC) researchers are investigating how the 2010 and 2011 earthquakes have increased flooding risks in the greater Christchurch area.
They are also examining implications for critical lifeline systems and coastal communities.
Civil and natural resources engineering researcher Dr Sonia Giovinazzi and geography senior lecturer Dr Deirdre Hart are studying the increased likelihood of flood potential phenomena due to earthquake-induced geotechnical and secondary hazards as well as investigating the impacts that the combined flooding-earthquake risks might have on lifeline systems.
Project leader Dr Giovinazzi says that the combined ground subsidence and damages to storm water control system following the earthquakes might have affected the ability to meet the long-term flood protection levels that residents and businesses rely upon.
``When targeting the enhanced resilience of lifelines systems to natural disasters, we wrongly tend to regard hazards as discrete events,’’ Dr Giovinazzi says.
``The Canterbury earthquakes and the earthquake and tsunami event in east Japan in 2011 demonstrate the issues impacting the resilience of lifeline systems in relation to earthquake-induced multi-hazard interactions.’’
She is working with US and Japanese researchers to assess the vulnerability of lifeline systems from a multi-hazard perspective and to identify possible combined risk mitigation strategies.
``These issues require further investigation to understand how the multi-hazard impacts on lifeline systems may be cost-effectively mitigated.’’
The assessment of cascade multiple-hazards and their implications is particular relevant for planning risk mitigation strategies for coastal communities.
Coastal risk assessments need to be revisited because of the earthquakes. Dr Hart says lessons from Christchurch can make New Zealand’s coastal cities, like Auckland, Wellington and Dunedin, more disaster-resilient.
``Preparing and planning for future major events avoids exacerbating existing and future coastal hazards,’’ Dr Hart says.
``The events of 2010 and 2011 triggered extreme liquefaction, flooding, sub-aerial and submarine ground deformation, riverbank rafting and channel shrinkage, fine sediment pulses in tributaries, streams, estuaries and beaches, pollutant leakage into waterways and widespread failures of coastal and riverside lifelines networks.’’
The UC project is being funded by the Natural Hazard Research Platform of New Zealand and will include a masters postgraduate student soon to be appointed.
The research will be conducted in collaboration with crown research agencies NIWA and GNS Science, and with local and authorities including Stronger Christchurch Infrastructure Rebuild Team (SCIRT), Environment Canterbury and the Christchurch City Council.
Civil and natural resources engineers Dr Alessandro Palermo and Dr Tom Cochrane and geography researcher Dr Christopher Gomez are also working on the project.
Dr Sonia Giovinazzi.