INFRASTRUCTURE RESILIENCE WHAT DOES IT MEAN AND HOW CAN IT BE INTEGRATED INTO ASSET MANAGEMENT

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1 INFRASTRUCTURE RESILIENCE WHAT DOES IT MEAN AND HOW CAN IT BE INTEGRATED INTO ASSET MANAGEMENT Philip McFarlane, Opus International Consultants Ltd Abstract New Zealand s Local Government Act requires Councils to provide for the resilience of infrastructure assets. But what does resilience mean in this context? How can the level of resilience be assessed? What is an acceptable level of resilience? How can community expectations regarding resilience be balanced against requirements to manage growth, service standards and concerns about aging infrastructure? To address these questions the paper will draw on preliminary findings from research work being undertaken into the seismic response of underground infrastructure. This research is being sponsored by the Ministry of Business, Innovation and Employment. A methodology for assessing vulnerabilities to earthquakes and for improving robustness will be outlined. This methodology will then be broadened out to provide a framework for ascertaining an appropriate level of resilience to natural disasters in general. Key words: Resilience, Asset Management. Earthquakes, Natural Disasters Introduction In September 2010 a magnitude 7.1 earthquake struck near Christchurch in the South Island of New Zealand. This event was followed by a series of aftershocks, the strongest of which occurred in February 2011 and June Significant damage was sustained to both above ground and underground infrastructure. In 2012 Opus Research and GNS were commissioned by the Ministry of Business, Innovation and Employment (MBIE) to undertake research into the seismic response of underground services. The research involves: literature research, assessment of failure records, finite element analysis and physical testing. The guidelines developed through the research will cover: Assessment of vulnerability Design for improved resilience Improved materials & installation practices to improve resilience The case for Resilient Infrastructure It appears that high-impact, lowprobability' disaster events are occurring more often, with 2011 being the most expensive year in history in terms of economic losses (Swiss Re Ltd, 2015). Each year more than 200 million people are directly affected by droughts, floods, tropical storms, forest fires and other hazards. (Pan American Health Organization, 2006) These events can also have widespread effects due to the increasing connectedness of the global economy.

2 There is therefore a strong case for improving the resilience of infrastructure as articulated in this quote from the Chengdu Declaration of Action, August There is no such thing as natural disasters. Natural hazards floods, earthquakes, landslides and storms become disasters as a result of human and societal vulnerability and exposure, which can be addressed by decisive policies, actions and active participation of local stakeholders. Disaster risk reduction is a no-regret investment that protects lives, poverty, livelihoods, schools, businesses and employment. Investing in improvements to the resilience of infrastructure can demonstrate a legacy of leadership, provide economic growth and job creation and result in more liveable communities. The Legal Requirements In New Zealand the Civil Defence Emergency Management (CDEM) Act 2002 requires a comprehensive riskmanagement based approach to hazard management, comprising risk reduction, readiness, response and recovery. Section 60 of the Act defines certain entities such as those organisations responsible for provision of water, wastewater and electricity services, among others, to be Lifeline Utilities. The Act requires Lifeline Utilities to ensure that they are able to function, if necessary at a reduced level, during and after an emergency, and requires them to participate in CDEM planning. Section 102B of the Local Government Act 2002 requires councils to prepare an infrastructure strategy for at least a 30 year period. Infrastructure Strategies are required to be prepared for water supply, sewerage and treatment and disposal of sewage, stormwater drainage; flood protection and control works; and the provision of roads and footpaths. The infrastructure strategy must outline how the local authority intends to manage its infrastructure assets, taking into account the need, amongst other requirements, to provide for the resilience of infrastructure assets by identifying and managing risks related to natural hazards and by making appropriate financial provision for those risks. How is Resilience Defined Resilience is defined as the ability of a system and its component parts to anticipate, absorb, accommodate, or recover from the effects of a shock or stress in a timely manner (IPCC, 2011). Resilience differs from standard engineering practice where it is assumed that infrastructure can be build strong enough to withstand events. Instead resilience approaches assume that infrastructure may be damaged and attempts to lessen consequential effects. Resilience approaches also place more emphasis on the effect of damage on the system as a whole rather than individual components. Figure 1 shows the concept of resilience in a schematic form. Key points to note are: Natural disasters affect the performance of infrastructure systems, which in turn affect the wellbeing of communities. Mitigation measures can reduce the amount of infrastructure damaged by an event. Recovery controls can reduce the impact of damage through measures such as providing alternative supplies, speeding up the response or through the provision of community support and communication measures. Resilience planning needs to consider that disasters do not always occur in isolation. Multiple events may occur at the same time.

3 Figure 1 Concept of Resilience Benefits of Resilience The Global Assessment Report developed by the United Nations Office of Disaster Risk Reduction highlights examples where organisations have reaped benefits in the ratio of 1:10 for their critical infrastructure prevention investments. The American Society of Civil Engineers estimates that federal spending on levees pays for itself six times over. (Wimmers, 2013) In New Zealand the utilities company Orion have estimated that the $6 million they had spent on seismic strengthening saved them $30 to $50 million in direct asset replacement costs following the Canterbury earthquakes of 2010 & The balance between costs and benefits is even more pronounced when societal benefits are taken into account (Kestral Group Ltd, 2011). The effects of disasters and the benefits of resilience are of course far more wide reaching than just the cost of replacing the original asset as shown the Resilience Wheel that has been developed by San Francisco City. Figure 2 - Resilience Wheel Challenges in Developing Business Cases for Resilience Often business cases attempt to justify resilience improvements based solely on the asset itself, i.e. the cost of replacement compared against the odds of an event occurring. However this approach is too narrow and it is very difficult to justify resilience projects on this basis. There is however a trend to take a more holistic approach to decision making. For example the Better Business Cases approach which is advocated by the National Infrastructure Unit requires projects to be evaluated against a multicriteria approach that includes: there is a compelling case for change "Strategic case"

4 the way forward optimises value for money "Economic case" the potential deal with the market is commercially viable "Commercial case" the proposal is affordable "Financial case" the proposal can be delivered successfully "Management case" 1. Performance of the ground has far more effect on pipe damage than the forces that result directly from the earthquake. It can be seen from Figure 3 that peak ground acceleration (PGA) did not significantly influence break rates, but Figure 4 shows that the extent of liquefaction had a significant effect. Other challenges in developing business cases for resilience projects include: It is often difficult to explain why there needs to be a sense of urgency for resilience improvements with other more immediate issues taking precedence. It is difficult to articulate risks in a manner that the public can comprehend. There is a lot of uncertainty and unknowns by the very nature of resilience planning. Priority is often given to projects with more certainty. Behavioural and psychological studies have identified that people tend to focus on lower impact, more probable risks. As a consequence risks can sometimes be underestimated. To overcome these challenges there needs to firstly be a robust processes to evaluate and prioritise resilience projects. Then the proposed projects need to be communicated to the public and decision makers in a manner that they can readily understand, recognising that they may view risks in a different way to expert risk assessors. Key Learnings from Canterbury Earthquakes Key learnings that have been gained from studying break data and service records for the potable water and wastewater systems following the Canterbury Earthquakes of 2010/11 include: Figure 3 Effect of PGA on Watermain Breaks Figure 4 Effect of Liquefaction on Watermain Breaks 2. The location of pipework in relation to watercourses influences the amount of pipe damage. It can be seen from Figure 5 that if the ground liquefies then the closer a watermain is to a watercourse the more likely it is to be damaged.

5 leaks that occurred on service connection. Figure 5 Effect of Distance from Watercourse on Watermain Breaks 3. The performance of the ground influences the ability of the system to remain in service. Experience in Christchurch was that if the ground liquefied then the wastewater system blocked regardless of the amount of damage sustained. 4. The time it takes to restore service is affected by both the soil conditions and the amount of damage incurred. In Christchurch the earthenware portions of the wastewater system that were located in liquefied ground tended to take the longest to restore to service as sand continued to enter the system through pre-existing faults and damage from the earthquake. On the other hand it took less time to restore the PVC portions in liquefied ground as although they initially blocked they tended to not re-blocked once they had been cleaned. Likewise service was able to be restored to earthenware systems in ground that did not liquefy fairly early on in the recovery process. 5. The quantum of damage sustained to non-critical pipes often controlled the time it took to restore service. For example the lifting of the boiled water notice on the potable water system was largely governed by the time it took to repair the multitude of small 6. Alternative means of providing service can be used but they take time to install and the public can only tolerate them for so long. For example in Christchurch areas were serviced for a significant time using portaloos placed on the berm outside properties. Over time as the wastewater system was restored to provide intermittent service the portaloos were replaced with portable chemical toilets that could be used inside homes. These in turn were replaced where necessary by chambers installed outside properties that enabled the occupants to use their wastewater system as normal with waste being removed by sucker trucks. 7. Restoration of service is multi-faceted. It has been identified from studies after the Los Angeles earthquake (Davis, 2011) that it is an oversimplification to consider the restoration of a service as one element. Instead there are different categories of service that need to be considered. For example, water supply can be categorised into water delivery, quality, quantity, fire protection, and functionality. The time it takes to restore these service categories can vary significantly with some categories being restored within hour with others taking many weeks or even years. 8. Restoration of service involves several phases as shown in Table 1. Priorities and needs change as restoration progresses through these phases. It may take many years to fully restore service to the preearthquake condition.

6 Table 1 - Operating Phases (Wellington Lifelines Group (Preston, 2015)) Service Category Description Emergency Services may be completely disrupted and uncontrolled Survival Controlled services but limited and with significant disruption Operational Full Near normal service delivery but with notifiable outages and significantly increased operating costs As, or better than, pre-event Framework for Improving Resilience As identified earlier in this paper there is a need for a robust process for assessing resilience projects and for evaluating resilience projects against other types of projects. To this end the following process is recommended. Establish minimum post event levels of service. Minimum post event levels of service should be established in collaboration with local authorities, community groups and emergency services. The minimum level of service has two components: The target level of service. Table 2 gives an example of minimum post disaster levels of service established for water supply in El Salvador. The length of time for which the level of service will be provided. These two items are interrelated, e.g. communities may tolerate a minimal level of service for a short period of time, but would require a higher level of service if it is going to take a long period of time to restore service to pre-event conditions. Therefore minimum levels of service should be established for each of the post event operating phases. Levels of service also have a spatial component. For example hospitals and possibly business areas may require a higher level of service for the community function after an event. Table 2 Example of Minimum Levels of Service for a Water Supply (UNICEF, 2006) Basic Indicators for Water during Emergencies and Disasters Access to water and available amounts Average amount of water for drinking, cooking, and personal and domestic, hygiene: 15 litres per person daily. Supply of water in health centres: litres per patient per day. Maximum allowable distance between houses and water collection point: 500 metres. Water collection points should be maintained so that adequate amounts of water are consistently available. Water quality New sources of water that must be used because of an emergency situation should contain no more than 10 faecal coliforms per 100 ml. Concentrations of residual chloride in piped water should be milligrams per litre, and turbidity should be less than 5 NTU. Total solids dissolved in water should not exceed 1,000 milligrams per litre.

7 Undertake a vulnerability assessment The amount of damage likely to occur can be estimated from fragility curves such as those shown in Figure 4 & Figure 5. Knowing the extent of damage it is possible to identify the sections of system where service may not be able to be provided and the population and the types of facilities affected. Estimate Restoration Time Response plans can then be developed and the time it will take to restore service to above the minimum level of service criteria can be estimated. Some of the key points highlighted from the Canterbury earthquakes that should be considered are: Service can be provided through alternative measures, e.g. portaloos for wastewater or potable water tankered in. However time and infrastructure is required to implement these measures. Restoration time is influenced by the number of repair crews available and probably more importantly the resources available to manage and direct the crews. Undertaking repairs in post disaster conditions can be very difficult, e.g. extensive dewatering is often required to repair pipes in liquefied ground. Identify resilience improvements Possible projects may include measures to improve: Robustness, i.e. strengthening sections of the system to reduce the likelihood of it breaking. Whilst the tendency is to consider making critical infrastructure more robust, this also apply to low critical sections, e.g. advancing renewal of earthenware wastewater pipes replacing them with more robust PVC pipes. Redundancy, i.e. providing multiple pipes to service an area. Ease of Repair, e.g. reducing the depth of pipes in areas subject to liquefaction. Infrastructure for alternative supplies, e.g. installation of connections to enable potable water to be provided to community buildings via tankers. Analyse improvement projects The impact of these measures on reducing the number of people affected by events can then be assessed and resilience measures prioritised. The approach outlined above should be undertaken for each of the post disasters operating phases described in Table 1. Conclusion The recent Canterbury earthquakes highlighted to New Zealanders our vulnerability to disasters. To improve resilience the CDEM Act 2002 and the Local Government Act 2002 require local authorities to assess and prepare for events. Resilience improvements have in some cases generated benefits in excess of ten times the cost involved. However it is often difficult to justify resilience improvements against projects with more immediate benefits. This paper has outlined a structured approach to the identification and assessment of resilience projects, where projects are evaluated against their contribution to the improvement of post disaster levels of service. This approach will be developed further and will form the basis of a set of guidelines being prepared by Opus Research and GNS under a commission from the Ministry of Business, Innovation and Employment. Acknowledgements Greg Preston, University of Canterbury Quake Centre Cheryl Bai, Opus International Consultants Ltd

8 Jasmin Callosa-Tarr, Opus International Consultants Ltd Bibliography Brenice Lee and Felix Preston, w. G. (2012). Preparing for High - impact Low-probability Events, Lessons from Eyjafjallajokull. London: Chatham House. Carne, S. (2013). Infrastructure Restoration and Resilience after Natural Disasters - What can we Learn from Christchurch, Pacific Island and Australian Experiences? IPWEA NZ, (p. 12). Rotorua. Davis, C. A. (2011). Water System Services and Relation to Seismic Performance. 7th Japan-US- Taiwan Workshop on Water System Seismic Practices (p. 12). Niigata, Japan: JWWA/WRF. Government Office of Science. (2011). Blackett Review of High Impact Low Probability Risks. London: Government Office of Science. IPCC. (2011). Special Report on Managing Risks of Climate Extremes and Disasters to Adance Climate Change Adaption. Geneva: IPCC. Kestral Group Ltd. (2011). Resilience Lessons:Orion's 2010 and 2011 Earthquake Experience. Ministry of Civil Defence & Emergency Management. (2014). Lifeline Utilities and CDEM, Director's Guidelin for Lifeline Utilities and Civil Defence Emergency Management Groups(DGL 16/14). Wellington: Ministry of Civil Defence & Emergency Management. Pan American Health Organization. (2006). The Challenge in Disaster Reduction for Water and Sanitation Sector: Improving quality of life by reducing vulnerabilities. Washington, D.C: PAHO. Preston, G. (2015). Level of Service Performance Measures for the Seismic Resilience of 3 Waters Network Delivery. IPWEA (p. 13). Rotorua: IPWEA. Roche Mahon, S. B. (2013). Evaluating the Business Case for Investment in the Resilience of the Tourism Sector of Small Island Developing States. Canterbury, New Zealand: Lincoln University. Swiss Re Ltd. (2015, March 25). Sigma 2/2012: Natural catastrophes and man-made disasters in Retrieved from gma_22012_natural_catastroph es_and_manmade_disasters_in_ 2011.html UNICEF. (2006). The Sphere Humanitarian Charter and Minimum Standards in Disaster Response. Standard 1 on water supply: access to water and available quantities.. El Salvador: UNICEF. UNISDR. (2015). Global Assessment Report on Disaster Risk Reduction - Economic Approach to Support Public Investment Planning and Financing Strategy for DRR2015. UNISDR. Wimmers, A. (2013). Building the business case for resilience investment. Insight, The Global Infrastructure Magazine,

9 Author Biography Philip McFarlane is Director of Global Asset Management at Opus International Consultants Ltd. He is responsible for the growth of the company s asset management market globally. Philip has a background in the planning, condition assessment, design and rehabilitation of wastewater, stormwater and potable water systems. He has over 30 years experience in civil engineering in New Zealand, Asia and England. In 2010 he was elected as a Fellow of the Institution of Professional Engineers of New Zealand for advancing engineering practice in the field of trenchless technology. Following the Canterbury earthquakes he has been involved in recovery and rebuild activities in Kaiapoi and Christchurch. In 2011 he lead one of the design teams in the SCIRT alliance and continues to have an ongoing role with their design activities. He is currently team leader of the research project into the Seismic Response of Underground Utilities being undertaken by Opus Research and GNS which has been commissioned by the Ministry of Business, Innovation and Employment (MBIE).