Executive Summary
Due to its location on the Pacific Ring of Fire, New Zealand is very prone to earthquakes, experiencing approximately 15,000 each year. About 150-200 are strong enough to be felt and large, destructive earthquakes occasionally occur. On 22 February 2011, a magnitude 6.1 earthquake hit Christchurch, New Zealand causing $40 billion in damages, 181 deaths, 1,500 injuries, and damaging approximately 100,000 buildings (U.S. Geological Survey, 2011; see also Kaiser et al., 2012).
The Christchurch earthquake served as a reminder to Wellington’s engineers, politicians, building owners, and heritage preservationists to continue their efforts to preserve the city’s structural assets. Many of Wellington’s buildings have been assessed as earthquake prone, meaning they meet less than 33% of the New Building Standard (% NBS). Such buildings must be strengthened or destroyed, forcing a difficult choice upon owners who may lack funds for upgrades, especially owners of buildings with special cultural value, such as heritage, religious, or community buildings. Heritage buildings give Wellington a sense of identity, an aspect that the public does not want to lose.
This project assisted the Crown-Research Institute GNS Science by collecting the opinions of the greater Wellington public and supplementing them with the experiences and opinions of field experts in order to develop an overview of opinions, perspectives, and expertise from which to seek common ground. The opinions of the three main stakeholders (the public, engineers, and church communities) were collected through public surveys, interviews, and focus groups. The recommendations developed and presented to GNS Science aim to stimulate an increased collaborative effort between these stakeholders in the hopes that understandings can be reached surrounding the balance of life safety and building preservation.
Specifically, we fulfilled four objectives:
- Establish public opinion on the monetary value and societal significance of both community and heritage buildings in the Greater Wellington Region (GWR).
- Assess public perception towards buildings tagged as earthquake prone.
- Collect the professional opinions of representatives of the structural engineering community concerning current building assessment techniques and future pending building code legislation.
- Collect information on the experiences of church communities and the New Zealand Historic Places Trust to better understand the challenges associated with the preservation of heritage buildings.
From these objectives, we developed a method that guided our research and explored the tensions surrounding the need for life safety versus building preservation.
Figure 1: Map of project objectives illustrates this process.
Objective 1: Establish public opinion on the monetary value and societal significance of both community and heritage buildings in the Greater Wellington Region.
This first objective helped us determine where tensions in our project aligned. We developed a public survey and administered it to 200 respondents in various areas within Wellington, Lower Hutt, and Porirua. This data represents the core of our project.
Objective 2: Assess public perception towards buildings tagged as earthquake prone.
Meeting our second objective established the level of risk that people associate with being in or around a building that has been tagged as earthquake prone. This data was collected from a question on our public survey and from our focus groups.
Objective 3: Collect the professional opinions of representatives of the structural engineering community concerning current building assessment techniques and future legislation.
Our third objective developed a better understanding of the current engineering assessment techniques from those who conduct them and it gauged their opinions on how methods should change in the future. We discovered that a proposed amendment to current legislation could standardize the assessment process. To gain the professional opinion of engineers on potential benefits of the pending legislation we conducted two focus groups with structural engineers from the GWR and we interviewed a member of the New Zealand Society for Earthquake Engineering (NZSEE).
Objective 4: Collect information on the experiences of church communities and the New Zealand Historic Places Trust in an effort to better understand the challenges associated with the preservation of heritage buildings.
Our fourth objective explored some of the challenges building owners faced when upgrading their buildings. Heritage building owners are restricted in how they can change their buildings; structural and historical requirements can conflict. We conducted interviews and focus groups with heritage building owners, members of various church communities, the Wellington City Council (WCC) and members of the New Zealand Historic Places Trust (NZHPT).
In addition, we met with the Wellington Region Emergency Management Office (WREMO) and discussed ways to integrate our project with one of their ongoing pre-disaster projects addressing questions such as which buildings should be reestablished first after a big earthquake. Upon completion of the project we sent a concise set of recommendations and findings concerning community buildings to WREMO (see Appendix I).
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Findings
Reviewing information collected from our public survey, focus groups, and interviews, led to several findings.
I. – The current building assessment practices are inconsistent, causing considerable variability in building assessment scores. In one focus group, a building owner in New Zealand had five different engineers conduct initial assessments on his building and received five different scores ranging from earthquake prone to very safe. It was discovered that each engineer used a different technique; some of these techniques included a street view assessment, an inspection of original building blueprints, and a detailed interior inspection of the building. Each of these assessment practices is valid with current legislation. Engineers we spoke with agreed that a standardization of inspection techniques is needed, noting they each had different methods they personally prefer.
II. – Heritage building owners are restricted in their ability to update buildings that are earthquake prone or at risk of earthquake damage (0-66% of New Building Standard). Before a significant change can be made to a heritage building, an owner must apply for permission from the NZHPT, which ensures that heritage value is not lost in the process. Preserving heritage value has become a challenge in the larger scope of improving a building’s safety score. In a focus group, we learned that a church community wanted to remove a bell tower which was causing the building to be earthquake prone. However, due to its classification as a Category I heritage building, they could not remove the bell tower. In another case, a building owner was trying to lose the building’s heritage status to have more freedom to upgrade the building.
III. – Despite the availability of multiple external funding options for upgrading heritage buildings, owners still find it difficult to afford retrofitting their buildings. Upgrading a heritage building can be very expensive due to its age and construction; most were not built up to current building standards, thus require a lot of retrofitting work. Currently, building owners can apply to receive a grant from different sources including the National Heritage Preservation Incentive Fund (from the NZHPT), the Wellington City Council Built Heritage Incentive Fund, and the Lottery Environment and Heritage Committee (from the Department of Internal Affairs). However, due to the demand for funding, these agencies in most cases can only partially fund any given retrofitting project. Building owners are left to cover most, if not all of the funding. It can take owners years, sometimes decades, to acquire the necessary funds on their own accord. Meanwhile, their buildings pose a safety risk to those around them and the functionality of the building is significantly lessened.
IV. – The public wants to see heritage buildings preserved and values them most for their architectural, historical, and cultural significance. In our survey, we asked members of the public if they thought it was important to preserve heritage buildings and 69% agreed or strongly agreed with this statement. We then asked why they valued heritage buildings and the most common responses were for historical, cultural, and architectural reasons. Additionally we found that religious heritage buildings were more valued for these reasons than for religious ones. This indicates that even though members of the public may not value buildings for their intended function, the public still finds visual and cultural value in the city’s religious heritage buildings.
In the open response section of the survey, members of the public expressed an interest in preserving the city’s charm and character. Many expressed concerns that Wellington might become like Christchurch, which lost a majority of its heritage buildings in the 2011 earthquake. The public wanted measures to be taken now to better preserve the iconic buildings of Wellington.
V. – There are specific heritage buildings within the Wellington Region that the public would like to see preserved above all others. In our survey we asked members of the public if there were specific heritage buildings in the region they would like to see preserved above all others and four buildings topped the list: Wellington Town Hall, Saint Mary of the Angels, Old Saint Paul’s church, and the Old Parliament Building.
VI. – The public is willing to contribute financially to upgrade heritage and community buildings if an increase in rates was established. In the public survey, we asked members of the public that if they had to use rates to contribute towards upgrading buildings, what percentage increase would they feel most comfortable accepting. Approximately 77% of those surveyed felt comfortable with at least a 1% increase in their rates for both heritage and community buildings. This finding illustrates how the public financially values the city’s buildings through their willingness to expend money for a preservation fund.
VII. – The public does not have a common perception of safety risks associated with earthquake prone buildings. In a survey question, we asked members of the public to rate, on a scale of very unsafe to very safe, how they felt when in or around a building that was tagged as earthquake prone. In reviewing the data the most popular response was neutral, yet answers were distributed across all possible responses. This indicates that the public does not have a common perception of the actual safety risks associated with earthquake prone buildings. Additionally, in focus groups, we found that building owners had a wide range of responses to their buildings being assessed as earthquake prone. Some heritage churches continued to use their buildings and just increased the earthquake risk notices in and around their buildings, while others shut down their buildings until they were upgraded to a certain % NBS. In conclusion, the public has a wide mix of reactions to an earthquake prone status.
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Recommendations
After reviewing our findings and background research, our team developed a list of recommendations for our sponsor, GNS Science, as well as for other stakeholders such as the WCC, the NZHPT, the WREMO, structural engineers and building owners:
- That earthquake related building assessment practices be standardized in an effort to promote more consistent and thorough building evaluations. It is further recommended that city councils, the central government, and the New Zealand Society for Earthquake Engineering establish a regular assessment training course for all structural engineers who conduct Initial Evaluation Procedures (IEP) and Detailed Engineering Evaluations (DEE) to assess the status of a building.
- That local authorities further research ways to involve public contributions in the preservation of heritage buildings.
- That the Wellington City Council consider developing new earthquake prone building notices that are more noticeable and informative to increase the public’s knowledge and awareness of earthquake prone buildings and the risks involved.
- That all involved stakeholders increase their collaboration and communication through the creation of a forum where anyone can express their concerns, work through challenges, and develop solutions.
These recommendations are a step in the right direction towards defusing tensions between the major stakeholders as they seek to balance life safety and preservation of community and heritage buildings.
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