Climate Change – coast
South Dunedin programme
We have been collecting and analysing information on the natural hazard risk facing South Dunedin (The Natural Hazards of South Dunedin, ORC, July 2016) and we continue to invest in research in this area.
ORC has a complementary programme of technical work underway to provide a better understanding of the South Dunedin natural environment, and how the physical environment influences natural hazards and the likely impacts of climate change in Dunedin. We started in 2009 with three bores to find out more about how groundwater levels were impacted by the sea and rainfall and a fourth was installed in 2014.
The scope of this programme now extends beyond the South Dunedin area. It also encompasses low-lying areas around the coast of Dunedin’s central business district (CBD), from the Oval to the University of Otago (harbourside).
The aim of the programme is progressing the development of a multi-hazard Climate Change Adaptation Plan for low lying areas in Dunedin city. Find out more about this programme and the history of the area.
In 2018, ORC joined the NZSeaRise venture, in collaboration with the research trust of Wellington’s Victoria University and GNS Science. The project objective is to improve sea-level rise projections for New Zealand, to better anticipate and manage the impacts of rising sea level on low-lying cities. The project will deliver an authoritative, scientifically-robust set of national sea-level rise projections to the end of the 21st century and beyond.
South Dunedin has been selected as a regional case study as it is a low-lying, densely-populated urban area likely to be impacted by sea-level rise. The case study outcome will be used to develop planning and risk assessment toolkits for planners, decision makers, iwi and our community who require technical and risk information to effectively adapt to sea-level rise.
Our contribution to the project is to improve understanding of groundwater and to work with GNS scientists to collate information about the physical environment of South Dunedin. This will help inform a robust geological model of the area. The NZSeaRise project is due for completion in June 2022.
ORC and DCC are also working collaboratively to make sure the data will be shared collectively ensuring its effective use.
Find out more information about South Dunedin.
Green Island sea-level recorder
We have also installed a sea-level recorder at Green Island, off the coast of Dunedin. The data from this, after quality checking, is supplied by NIWA to the Permanent Service for Mean Sea Level, a global data bank for long term sea level change information from tide gauges based at the National Oceanography Centre in Liverpool (UK).
We are supporting Waitaki District Council in their District Plan review by providing technical support. We contracted the National Institute of Water and Atmospheric Research (NIWA) to produce a report on the coastal hazards of the Waitaki District. It looks into coastal erosion and inundation, factoring in the effects of climate change and rising sea-levels.
The report can be found here.
Investigations on the potential effects of climate change on the Clutha Delta are also ongoing (Natural Hazards on the Clutha Delta, ORC, May 2016). A programme of technical work including monitoring is currently being scoped. The purpose of this work is to help develop an adaptation plan in collaboration with the Clutha District Council, and to inform our next Long-term Plan and the decisions around flood protection and drainage infrastructure as part of the Lower Clutha Flood Protection and Drainage Scheme.