Our city, people, houses and infrastructure could be impacted by a number of natural hazards such as earthquakes, erosion, extreme rainfall, and tsunami.
The aim of the Resilience Project is to provide for robust infrastructure and informed land use planning, so we can improve the city’s resilience to natural hazards.
Understanding the risks and their consequences is a critical element in this process. Then the way we respond, with design, adaptation or retreat, will bring us closer to the goal of a resilient city.
The Resilience Project used updated data on natural hazards to quantify their impact on the city’s infrastructure assets. Then the vulnerability of the city’s assets was evaluated and mitigation against these hazards prepared.
Natural hazards and impact on infrastructure
We have been researching, mapping, planning for and informing our community about natural hazards for over 20 years now. We continue to collect new data and update existing data on a rolling basis – to ensure it covers our whole city, and incorporates updates in scientific knowledge, guidelines, and legislature, and responds to changes associated with climate change.
Read more about natural hazard studies and data
The Resilience Project evaluated the probability of these natural events, and the impact they may have on the city’s infrastructure.
Evaluating the vulnerability of assets and determining appropriate mitigation
Continued operation of the city’s infrastructure during a natural hazard event is critical to surviving and recovering from a disaster. Of particular focus is the capacity of our roads and water systems to absorb these shocks and recover quickly afterwards.
We mapped all natural hazards over the city’s transport and water networks to identify exposed assets, scope projects and associated cost. Over 300 projects have been identified that will help reduce risk and improve resilience.
We’ve identified risk hot spots where not only single, but multiple critical assets are impacted by numerous hazards. Each hot spot has been analysed in terms of risk. This is a measure of likelihood of a natural hazard event and the consequence of that event, with outage times factored in to provide a risk rating for the project area as it is currently. As a result, these hot spots have been established as projects, which can incorporate one or several assets.
For all identified projects, a concept design of mitigation measures has been carried out. As part of the modelling, we took the opportunity to explore various options: to completely remove assets from the hazard area or to strengthen the existing assets with new materials. The risk factor was then re-evaluated in the post-mitigation condition. This provides a risk rating before and after the mitigation and gives us a measure of how well the project contributes to city resilience.
The key findings show:
- 315 projects across the city have been identified to mitigate natural hazard risks to infrastructure.
- Many projects integrate with previously forecast renewals and upgrades which are already part of council’s asset management program.
- The estimated cost of the total improvement programme is between $850 and $950 million. This includes $60 to $120 million of pre-budgeted renewals.
- The programme of work can be implemented over a 30-year period, subject to confirmation of funding.
Every project completed will make Tauranga and its communities more resilient. They add capacity to absorb more severe natural hazards and allow us to recover more quickly from damage. Such projects contribute to a safer living environment for all.
Climate change projections are factored into the natural hazard studies and into individual project designs. This means we are building a climate resilient community and economy.
We are now implementing some of the projects identified as a priority, which range from replacing pipes, protecting roads or moving key infrastructure. We are also incorporating some of the resilience projects as part of our current city upgrade and renewals projects. We will be updating our risk assessment as these projects are completed to determine the level of resilience risk improvement that has been achieved.