Canterbury Earthquake Sequence Research Articles

A decade of shaking in the Garden City: the dynamics of preparedness, perceptions, and beliefs in Canterbury, New Zealand, and implications for earthquake information

IntroductionThis study explored earthquake preparedness over time—before, during, and 10 years after the Canterbury Earthquake Sequence (CES) in New Zealand (NZ; known as Aotearoa in te ao Māori).MethodSurveys of Canterbury residents were conducted in 2009, 2013, and 2021, using variables derived from Community Engagement Theory (CET). The surveys measured earthquake perceptions and beliefs, participation and engagement, and preparedness actions. Results were compared across the three samples.ResultsFindings indicate that perceptions and beliefs (e.g., risk perception, outcome expectancy beliefs), and types of preparedness actions taken (e.g., collection of survival items, structural preparedness, community and/or agency relationships), differed over time, depending on people's experiences before, during, and after the CES. For example, during and after the CES, people were more likely to believe that preparing provided a benefit to daily life, but less likely to think it could reduce property damage, perhaps due to people's experiences of disruption and damage during the earthquakes.DiscussionAn understanding of such dynamics can assist with the provision and timing of risk and preparedness information. This study highlights the importance of providing applicable and actionable preparedness information, that is relevant to people's experiences, throughout an earthquake sequence. Such information might evolve and change in focus over time depending on risks and needs. Focus could also be given to information that builds peoples beliefs and capacities to undertake preparedness in evolving situations. Understanding preparedness in the context of different experiences and timeframes is useful in helping update models such as the CET, where the dynamics of time might be better incorporated.

Long-term communication of aftershock forecasts: the Canterbury Earthquake Sequence in Aotearoa, New Zealand

On 14 February 2016, a magnitude (M)5.7 earthquake struck in Christchurch, Aotearoa, New Zealand. The shaking caused damage to historic facades, power outages, cliff collapses, rock falls, liquefaction but no reported injuries or fatalities. This Valentine’s Day earthquake was an aftershock in the Canterbury earthquake sequence (CES), which began on 4 September 2010 with the M7.1 Darfield Earthquake and included the destructive and fatal M6.2 Christchurch aftershock on 22 February 2011. This study eight months after the Valentine’s Day earthquake and six years after the initiation of the CES is the first to explore long-term aftershock forecast information and communication needs. The exploratory study also aimed to gather feedback on aftershock scenarios, an alternate form of communication of the forecast.The qualitative study involved workshops with emergency managers, public health officials, and members of the public in Christchurch. Key findings for long-term communication throughout an earthquake sequence include: 1. divergent earthquake experiences affect aftershock communication response and information needs; 2. understanding aftershock sequence behavior is foundational to sense-making when large aftershocks occur; 3. strategic earthquake sequence updates from the trusted science agency and local agencies could serve as important reminders for earthquake preparedness; 4. communication of aftershock forecast uncertainty could aid with both the credibility of the information and living with uncertainty, and 5. inclusion of impact information and preparedness advice into aftershock forecast scenarios could provide links to actionable information. The paper derives implications for research and practice of long-term communications during an aftershock sequence.

Groundwater monitoring infrastructure: Evaluation of the shallow urban and coastal network in Ōtautahi Christchurch

Study regionŌtautahi Christchurch, New Zealand Study focusUrban shallow groundwater monitoring networks are becoming widespread in New Zealand and globally. A reliable groundwater monitoring infrastructure is important to develop knowledge on water table aquifers in coastal cities like Ōtautahi Christchurch. Previous investigations have shown shallow groundwater vulnerability to salinisation and contamination in urban settings, and shallow groundwater exacerbates flooding from climate change and the impact of rising sea levels. New hydrological insights for the regionFollowing the 2010–2011 Canterbury earthquake sequence, shallow groundwater data acquisition and the establishment of a geotechnical database in Ōtautahi Christchurch provided unprecedented information on subsurface conditions. The installation of the groundwater monitoring infrastructure opened the field of New Zealand-based urban hydrogeological studies, including continuous measurements of groundwater levels. This study presents the hydrogeological context of Ōtautahi Christchurch, provides an overview of seismic impacts on groundwater, and documents the monitoring network’s development. Methods for assessing the monitoring network included field surveys and digital information review. The overall good condition and robustness of the network mean the dataset held by the city and regional councils should be more widely used to benefit the community. Implications for researchers and network asset managers mean that the maintenance and availability of the data should be prioritised. Records from urban shallow groundwater monitoring networks are becoming an essential source of information to manage urban water resources under climate change and sea-level rise conditions.

Experimentation, privilege, and difference: The politics of do‐it‐yourself urbanism

AbstractThe Canterbury Earthquake Sequence of 2010–2012 was devastating for Christchurch, New Zealand, a city built on a floodplain. The sequence resulted in widespread damage across the central business district (CBD) and residential areas. Alongside, and in contrast to, orthodox planning responses by the New Zealand Government, playful, creative, and temporary projects emerged in vacant spaces. These were designed to bring back life and energy to the city centre, and such types of activity are referred to by scholars as do‐it‐yourself (DIY) urbanism. A primary critique of DIY urbanism in the literature relates to how it has the potential to contribute to gentrification, despite its amateurish appearance and mildly subversive politics. In Christchurch, a venue built from pallets—known as the Pallet Pavilion—was constructed by an organisation known as “Gap Filler” with the help of volunteers. Gap Filler emerged after the first earthquake, inserting creative projects to bring back life and energy to the damaged CBD. By examining the Pallet Pavilion, we show that, despite its potentially gentrifying effects, DIY urbanism interventions may open up a more inclusive politics of the city. Also, and paradoxically, in the case of the Pallet Pavilion, the exercise of privilege made this inclusive politics possible.

Managed retreat and experimentation: realising opportunity in the Ōtautahi Christchurch residential red zone, Aotearoa New Zealand

ABSTRACT Managed retreat is becoming a prominent issue both nationally and internationally. This is due both to the threat of rising sea levels and the growing incidence of extreme weather events, but also reflects the increasing propensity for placing human assets in harm's way. We analyse how this observation plays out in Aotearoa, and offer a simple model, informed by our intergenerational perspective and mātauranga Māori. This model has three features: retreat, relocation, and re-imagining. It enables us to explore the capacity for positive outcomes to further lower long-term environmental and social risks. We apply the model to the Ōtākaro Avon river corridor in Ōtautahi Christchurch, formerly known as the residential red zone, created during the Canterbury earthquake sequence of 2010-13. We discuss what can be learned from the decade-long history of adaptation in the corridor as an exemplar for emerging areas of managed retreat elsewhere. By means of a thought experiment, we explore the potential of the area for provision of affordable, climate-resilient housing.

Standing upright here: critical disaster studies viewed from the Antipodes

ABSTRACT This article seeks to reinvigorate disaster scholarship, given the disastrous times we find ourselves in. In order to do so, we extend the spatial and temporal horizons of disasters, and consider them as normal processes as well as aberrant events. Knowledge need not exclusively emanate from the metropolitan centres of the Global North. We begin by examining the field’s ‘threshold concepts’, subjecting them to an urgent Indigenous evaluation. Second, as cities are the Anthropocene’s primary terrain, we illustrate the numerous ways in which the recovery from the Canterbury Earthquake Sequence offers global lessons. Third, leveraging understandings from the preceding sections, we orient towards a more hopeful intellectual frontier – a decolonised disaster studies as seen from the perspective of Aotearoa New Zealand. Since much disaster scholarship emphasises failure and loss, here we consider what will be gained through a fuller appreciation of mātauranga Māori.

Evaluating changes in shear wave velocity due to blast-induced liquefaction

Blast liquefaction tests were performed in Christchurch, New Zealand in an area that experienced extensive liquefaction during the 2010–2011 Canterbury Earthquake Sequence. To evaluate the changes in shear wave velocity (VS) of the soil profile in the vicinity of the blasting, multi-channel analysis of surface waves (MASW) testing was performed before the blast, immediately following the blast (within 0.5 h), 4 h post-blast, and 24 h post-blast. Three different array setups with varying lengths and number of geophones were analyzed to study the effect of array length on the ability of MASW to capture changes in VS within the blast area. Results of the study show that array length can have a significant effect on the measured changes in VS immediately following blasting due to averaging of the properties inside and outside of the area where blasting induced liquefaction developed; however, these changes decrease at 24 h. Full recovery of pre-blast VS was not observed for all layers at 24 h post-blast. This study provides data for measurements of VS rapidly following liquefaction, which are sparse in the literature.

National liquefaction loss database and event-level fragility functions

Liquefaction can be a significant contributor to loss due to earthquakes as observed during the Canterbury earthquake sequence or the 1995 Kobe earthquake. Geospatial liquefaction models can be used to estimate liquefaction extent after an earthquake but do not estimate liquefaction damage or impact. This article presents a liquefaction loss database for the United States and event-level fragility functions (EFFs) using aggregate liquefaction hazard measures (LHMs) derived from geospatial liquefaction models. The liquefaction loss database for the United States is developed by sampling earthquakes with Magnitude > 5.0 between the years of 1964 and 2019 in the continental United States and Alaska. Within this sample of 42 earthquakes, 11 resulted in liquefaction loss. Estimates were characterized by the type of infrastructure (e.g. transportation, utilities, and buildings) and the subcategory (e.g. for buildings: residential, commercial, and public), and then loss was estimated using the 2018-equivalent US dollar amount. When possible, loss estimates were obtained directly from the literature. Within this sample of 42 earthquakes, 6 events resulted in estimated monetary losses from liquefaction damage greater than 1% of the total event loss, including one with liquefaction damage greater than 10%. Using estimates for aggregate liquefaction hazard and population exposure derived from geospatial liquefaction models as LHMs, EFFs are presented using cost-based damage state (DS) thresholds in the United States. The fragility functions also include confidence intervals representing the uncertainty in probabilities of exceeding DS thresholds. Aggregate liquefaction hazard was found to be a preferred LHM for liquefaction loss, especially when evaluating transportation and building loss. Aggregate population exposure was found to be a better LHM for utilities. In addition, a second set of EFFs is presented using an expanded international dataset and DSs which are assigned relative to overall earthquake damage rather than cost-based DSs.

UNITE Project: understanding neurocognitive impairment after trauma exposure–study protocol of an observational study in Christchurch, New Zealand

IntroductionOur previous research has demonstrated significant cognitive effects of earthquake exposure 2–3 years following the Canterbury earthquake sequence of 2011. Such impairment has major implications for a population trying to...

Development of a seismic loss prediction model for residential buildings using machine learning – Ōtautahi / Christchurch, New Zealand

Abstract. This paper presents a new framework for the seismic loss prediction of residential buildings in Ōtautahi / Christchurch, New Zealand. It employs data science techniques, geospatial tools, and machine learning (ML) trained on insurance claims data from the Earthquake Commission (EQC) collected following the 2010–2011 Canterbury earthquake sequence (CES). The seismic loss prediction obtained from the ML model is shown to outperform the output from existing risk analysis tools for New Zealand for each of the main earthquakes of the CES. In addition to the prediction capabilities, the ML model delivered useful insights into the most important features contributing to losses during the CES. ML correctly highlighted that liquefaction significantly influenced building losses for the 22 February 2011 earthquake. The results are consistent with observations, engineering knowledge, and previous studies, confirming the potential of data science and ML in the analysis of insurance claims data and the development of seismic loss prediction models using empirical loss data.

3D Numerical Assessment of Rammed Aggregate Pier Performance under Dynamic Loading in Liquefiable Soils

Ground improvement (GI) techniques have shown promise in effective liquefaction mitigation, but the physical mechanisms governing their three-dimensional (3D) response during dynamic loading are not yet fully understood. To evaluate the 3D performance of one GI technique, the rammed aggregate pier (RAP), in-situ site characterization, full-scale field test data, and calibrated baseline constitutive soil model parameters are combined to model the 3D fully coupled hydromechanical response of natural (unreinforced) and improved (reinforced) soil profiles. To the authors’ knowledge, this contribution represents the first 3D model of a columnar-reinforced soil profile being calibrated using full-scale field testing. The field observations from the comprehensive ground improvement testing (GIT) program in New Zealand and insights from two-dimensional (2D) finite-difference analyses using constitutive model parameters calibrated against the field measurements were used. The developed 3D models were subjected to dynamic loads simulating the excitation generated by a vibroseis truck at one of the in-situ test sites of the GIT program, as well as unidirectional and bidirectional earthquake ground motions from the Canterbury Earthquake Sequence events. The 3D simulations showed that the improved soil profiles experienced reduced excess pore pressures and reduced dynamically induced shear strains compared to the natural, unreinforced soil models. The developed 3D finite-element predictions were compared and validated vis-à-vis the field observations of the GIT program. Compared to 2D analyses, 3D analyses provide a more accurate description of actual field conditions, and, for instance, it was observed that multidirectional shaking has a significant effect on liquefaction triggering, particularly for natural soil profiles. Finally, it was shown that soil densification around the installed pier elements and the lateral earth pressure increase within the densified soil and are the primary ground improvement mechanisms contributing to the reduction of dynamically induced shear deformations and excess pore pressure generation during earthquake shaking. It was also found that the permeability and shear stiffness of the installed RAP piers did not have a significant influence on the pore pressure response and shear strains developed along the centerline of the improved area.

Seismic effects of bracing irregularity of light timber-framed buildings

Most residential buildings in New Zealand are low-rise light timber-framed (LTF) buildings, constructed according to a prescriptive standard – NZS 3604:2011 Timber-framed buildings. NZS 3604:2011 tabulates the seismic demand and also specifies the test procedure for evaluating the seismic resistance of proprietary LTF walls, which are often plasterboard walls. Designers need to ensure the provided total seismic bracing capacity is at least equal to the total seismic bracing demand, provided that bracing arrangements satisfy the specified irregularity limits. The irregularity limits of bracing arrangements in NZS3604:2011 were established based on engineering rules of thumb rather than rigorous scientific evidence. Earthquake damage observed in the 2010/11 Canterbury earthquake sequence demonstrated that simple regular LTF houses performed well while irregular houses often had significant damage that was uneconomical to repair. This suggested that the irregularity of LTF buildings was an important factor responsible for the exacerbated earthquake damage. To quantify seismic effects of permissible irregularities in NZS 3604:2011 and provide scientific evidence for elaborating irregularity limits in NZS 3604:2011, three single storey LTF buildings with varying degrees of permissible plan irregularities were designed and their seismic performance was studied by conducting three-dimensional non-linear push-over analyses. For the non-linear push-over analyses, the in-plane behaviour of LTF walls and ceiling diaphragms were modelled using the models, developed based on NZ practice, as reported in previous research. The study revealed that permissible irregular bracing arrangements in NZS 3604:2011 could amplify lateral deflections significantly, in comparison with the regular counterparts. As a result, irregular LTF buildings within the scope of NZS 3604:2011 could be susceptible to damage due to excessive deformations in earthquakes and this suggests that the irregularity limits in current NZS 3604:2011 be reviewed and tightened.

The influence of multiple impedance contrasts on mHVSR site period estimates in the Canterbury Plains of New Zealand and implications for site classification

An experimental study of the fundamental period of vibration of geologic strata above multiple impedance contrasts is presented for the Canterbury Plains, a deep, complex sedimentary basin on the South Island of New Zealand. Microtremor Horizontal-to-Vertical Spectral Ratio (mHVSR) analysis was used at 152 locations to investigate the fundamental period of the strata above three significant impedance contrasts in the region: the Riccarton Gravel, the Banks Peninsula volcanic (BPV) rock, and the deep graywacke basement bedrock. Up to three mHVSR peaks were observed in many of the mHVSR curves, with the long-period (2–7 s) peaks controlled by the BPV and/or the underlying bedrock. As the thickness of the BPV increases, the response of the geologic strata above the basement bedrock was masked by the shallower BPV, effectively changing the definition of what constitutes the reference condition (i.e. engineering bedrock) for site response analyses. The mHVSR peaks matched the long-period amplification peaks observed in the response spectra calculated from ground motions recorded during the Canterbury Earthquake Sequence events, underscoring the importance of the identification and consideration of deep impedance contrasts in site classification.

Continuous-discrete hybrid Bayesian network models for predicting earthquake-induced liquefaction based on the Vs database

The Bayesian network (BN) method has been increasingly applied in predicting earthquake-induced liquefaction. Nonetheless, the existing BN models treat all factors of liquefaction, including discrete and continuous variables, as discrete variables using different discretization approaches in the prediction of earthquake-induced liquefaction. Information loss may occur in the discretization process of the continuous variables, which reduces the predictive accuracy of the BN model. To tackle this issue, a shear wave velocity (Vs) database is taken as an example in this study for developing mixed continuous-discrete BN models to improve the predictive accuracy of earthquake-induced liquefaction. First, the discrete and continuous variables are distinguished and the continuous variables are tested whether they approximately obey the Gaussian distribution. Second, discrete variables (e.g., liquefaction potential as binary variables) and continuous variables are simultaneously considered in structural modeling. Then, the conditional linear Gaussian distribution and Markov chain Monte Carlo approaches are used to construct two hybrid BN models. A 10-fold cross-validation test is used to demonstrate that the performance of the hybrid BN models is better than those of the discrete BN models or other methods such as logistic regression, artificial neural network, support vector machine, and naïve Bayes. The hybrid BN models are applied to the 2010–2011 Canterbury earthquake sequence to demonstrate their generalizability. This study finally discusses the difference in information loss and computational cost between the discrete and hybrid BN models.

Development of LSN-based pipe repair rate models utilising data from the 2011 Christchurch earthquakes

The Canterbury Earthquake Sequence (CES) adversely impacted built, economic and social environments. This included widespread physical damage to the water supply pipe network in Christchurch, resulting in long service disruptions. The transient and permanent ground deformations generated by the earthquakes in the CES caused a range of pipe damage, particularly in the MW 6.2 22 February 2011 and the relatively less damaging MW 6.0 13 June 2011 event. Damage to the pipes in both events was largely attributed to liquefaction and lateral spreading effects. Pipes made of ductile material (e.g. PVC, HDPE) sustained lesser damage (and therefore lower repair rates) compared to the pipes made of non-ductile material (e.g. AC, CI). In all cases, the repair rates (number of repairs per kilometre) typically increased with increasing liquefaction severity. Utilising the pipe repair dataset and Liquefaction Severity Number (LSN) maps generated from extensive geotechnical investigation following the CES events, new repair rate prediction models for water pipes subjected to liquefaction effects have been derived and are presented in this paper. Repair data from both earthquakes has been analysed independently and in combination, providing two sets of repair rate functions and different levels of uncertainty. Repair rate functions were first derived from pipes grouped by combination of diameter (i.e. ϕ < 75 mm or ϕ ≥ 75 mm) and material type (i.e. ductile or non-ductile). The models were then refined by adding correction factors for those material types and diameters with sufficient sample length. Correction factors were derived for AC, CI, PVC pipes of diameter ≥75 mm and for MDPE and HDPE80 pipes of diameter <75 mm. Galvanised Iron (GI) pipes performed poorly during the earthquakes, resulting in very high repair rates compared to the other non-ductile pipes of diameter <75 mm damaged in the network; this warranted a separate repair rate model to be developed for this pipe type. The proposed models can be used in risk assessment of water pipe networks; i.e. to estimate the number of pipe repairs from potential liquefaction damage from future earthquakes.

The Effects of Earthquake Experience on Intentions to Respond to Earthquake Early Warnings

Warning systems are essential for providing people with information so they can take protective action in response to perils. Systems need to be human-centered, which requires an understanding of the context within which humans operate. Therefore, our research sought to understand the human context for Earthquake Early Warning (EEW) in Aotearoa New Zealand, a location where no comprehensive EEW system existed in 2019 when we did this study. We undertook a survey of people's previous experiences of earthquakes, their perceptions of the usefulness of a hypothetical EEW system, and their intended responses to a potential warning (for example, Drop, Cover, Hold (DCH), staying still, performing safety actions). Results showed little difference in perceived usefulness of an EEW system between those with and without earthquake experience, except for a weak relationship between perceived usefulness and if a respondent's family or friends had previously experienced injury, damage or loss from an earthquake. Previous earthquake experience was, however, associated with various intended responses to a warning. The more direct, or personally relevant a person's experiences were, the more likely they were to intend to take a useful action on receipt of an EEW. Again, the type of experience which showed the largest difference was having had a family member or friend experience injury, damage or loss. Experience of participation in training, exercises or drills did not seem to prompt the correct intended actions for earthquake warnings; however, given the hypothetical nature of the study, it is possible people did not associate their participation in drills, for example, with a potential action that could be taken on receipt of an EEW. Our analysis of regional differences highlighted that intentions to mentally prepare on receipt of a warning were significantly higher for Canterbury region participants, most likely related to strong shaking and subsequent impacts experienced during the 2010–11 Canterbury Earthquake Sequence. Our research reinforces that previous experience can influence earthquake-related perceptions and behaviors, but in different ways depending on the context. Public communication and interventions for EEW could take into consideration different levels and types of experiences of the audience for greater success in response.

Seismic repair and retrofit prioritization framework

The 2010–2011 Canterbury earthquake sequence caused significant damage to the Canterbury District Health Board (CDHB) building stock. The extent of damage, post-earthquake changes to the seismic code, new legislation around earthquake-prone buildings, and ongoing changes to clinical service requirements created a challenging decision-making environment for capital works repair and retrofit. In this article, we present a framework designed to assess the seismic resilience of buildings from a holistic perspective and to determine appropriate levels of seismic retrofit. The framework design ensures that decisions are driven by building criticality in the context of a healthcare system. It helps users to balance life safety risk and the demands of delivering critical clinical services day to day: resulting in safe facilities that provide effective health services under a range of future conditions. Pilot application of the framework enabled the reprioritization of significant capital toward buildings that provide the most life safety and health service resilience benefits in the long term. The process and resulting framework from this project is applicable to a wider range of building owners navigating seismic retrofit decision-making and the emerging movement toward functional recovery–based building regulation.

Examining the long-term cognitive effects of exposure to the Canterbury earthquakes in a resilient cohort.

Although most people do not develop mental health disorders after exposure to traumatic events, they may experience subtle changes in cognitive functioning. We previously reported that 2-3 years after the Canterbury earthquake sequence, a group of trauma-exposed people, who identified as resilient, performed less well on tests of spatial memory, had increased accuracy identifying facial emotions and misclassified neutral facial expressions to threat-related emotions, compared with non-exposed controls. The current study aimed to examine the long-term cognitive effects of exposure to the earthquakes in this resilient group, compared with a matched non-exposed control group. At 8-9 years after the Canterbury earthquake sequence, 57 earthquake-exposed resilient (69% female, mean age 56.8 years) and 60 non-exposed individuals (63% female, mean age 55.7 years) completed a cognitive testing battery that assessed verbal and visuospatial learning and memory, executive functioning, psychomotor speed, sustained attention and social cognition. With the exception of a measure of working memory (Digit Span Forward), no significant differences were found in performance between the earthquake-exposed resilient and non-exposed groups on the cognitive tasks. Examination of changes in cognitive functioning over time in a subset (55%) of the original earthquake-exposed resilient group found improvement in visuospatial performance and slowing of reaction times to negative emotions. These findings offer preliminary evidence to suggest that changes in cognitive functioning and emotion processing in earthquake-exposed resilient people may be state-dependent and related to exposure to continued threat in the environment, which improves when the threat resolves.

Driving forces of population change following the Canterbury Earthquake Sequence, New Zealand: A multiscale geographically weighted regression approach

AbstractThe Canterbury Earthquake Sequence (CES), which includes the 2010 and 2011 Christchurch earthquakes, is one of the deadliest disasters in New Zealand history. Following the CES, displacement of the affected population occurred, leading to an out‐migration from affected areas and changes to places of residence. This paper investigates the spatial changes in population following the CES, using a multiscale geographically weighted regression (MGWR) analysis approach to examine if there is a relationship between population change within the Canterbury region, and potential driving forces across two time periods: 2006–2013 and 2013–2018. The findings of this study could assist in informing future decision making and planning for earthquake events and to increase the effectiveness of land use policy decisions for post‐disaster recovery in New Zealand.

Build Back Better and Long-Term Housing Recovery: Assessing Community Housing Resilience and the Role of Insurance Post Disaster

The purpose of this research is to better understand community housing resilience and the role of insurance using a Build Back Better Long-term Recovery Housing framework to analyze approaches and effects on long-term housing rebuilding and recovery. A comparative case study approach is taken to assess insurance policies and outcomes following Hurricane Katrina in New Orleans and the Canterbury earthquake sequence in Christchurch, New Zealand, both affluent urban communities with strong insurance markets. Framed within the context of “Build Back Better”, the community housing and insurance resilience assessment is based on five key indicators; governance, community resources, risk reduction, housing rebuilding funding (funding and speed of funding), and time compression (built environment and periods of recovery time). Public and private insurance schemes for both case studies are identified and are considered together with analysis of insurance claims and other sources of financial support. The findings and results show that recovery is the result of highly interdependent Build Back Better processes. The data suggests that insurance and governance systems greatly influences the onset and overall speed of recovery (time compression), thereby performing a major role in long-term recovery. This research provides an original contribution to disaster recovery knowledge by analyzing insurance claims from two well-documented natural disasters. Additionally, the paper proposes for the singular definition of community housing resilience.