Goals for effective coastal adaptation
Significant progress has been made in coastal adaptation over the previous years. The question now is: ‘What’s next?’. There are 8 main strategies for consideration.
Collect and analyse local sea-rise data
The SEAFRAME tide gauge should be reinstated at Port Stanvac so that:
- Accurate data will provide the basis for decision making over time.
- Policy responses to higher than expected rates of change due to rapid ice melt (or other drivers of sea level) could be developed now and predicated upon triggers in data collected locally (at Port Stanvac and Thevenard)7.
- Conversely, should data collected over time demonstrate a lack of escalation, or even a de-escalation, new local projections could be formulated, and policy relaxed.
7 Combined with satellite data (if this can be localised) 2 data sets would provide a powerful basis for decision making.
To be clear, this approach is over decades, and not just over a few years of the political cycle. We have an opportunity in this era to provide a legacy to future generations – the ability to predicate decision making upon local and accurate data. Any other approach is likely to be a political quagmire of individual interests and views.
The cost of reinstalling the tide gauge at Port Stanvac has been estimated at $309,0008. The cost of the installation should be viewed in the context that the state is likely to face increasing challenges in the courts, and the cost of mal-adaption decisions made in the light of poor data environment may be high. The cost should also be viewed in the context of the possibility of a rapid ice melt scenario. Local data will be imperative.
8 Feasibility study conducted by Bureau of Meteorology, 10 October 2017. Sources within Bureau of Meteorology state that the cost of installation should be shared by all levels of government.
Create a digital model of the coastline
A recent flurry of action of digital capture across the state has resulted in much of the coastline now having a digital baseline. The regions are yet to be captured, or recaptured due to data quality being too old or not at high enough resolution.
The following matters should be considered going forward:
- The capture to date has been piecemeal and ad hoc over time. This statement does not infer that the capture projects have been run poorly, but rather that there is no over-arching capture strategy.
- Digital models are absolutely essential as a platform upon which to model various sea-level-rise scenarios to envision plausible futures.
- The creation of a digital baseline is essential for monitoring change over time. The digital baselines will form the basis for evaluating change over the coming decades, and even centuries. This is a legacy issue for future generations.
- The resolution of the current digital models could be described as ‘adequate’, but higher resolution is desirable and achievable.
- Plans should be made now to recapture the data in 5 years time as a single project. These projects will become more cost effective over time. The efficiencies produced in the ability to compare changes digitally will also produce cost savings to the coastal Councils.
- Future capture of the entire coastline is not likely to be essential. However, recapture within within urban settlements is recommended at least once every 5 or 10 years, depending on the risk outlook.
The problem with many coastal studies is that they can be very expensive but they do not necessarily provide the outcomes from which to promote action. While writing this report I had a call from a CEO from smaller council who stated that they had spent $104,000 on a study but it did not tell them what they needed to know.
This is likely due to the number of variables and the lack of fundamental data. Speak to any coastal scientist and they will tell you that it is almost impossible to estimate the rate of erosion on a shoreline. The comparison of high resolution digital models will form a sound basis upon which to understand what is occurring in the coastal zone. Tracking change over time, will form the basis of more sound adaptation decisions.
Develop a system of coastal adaptation that is truly ‘bottom up’ and funded
Create a system of coastal assessment and adaptation (within urban coastal environments) that is truly ‘bottom up’. Any other approach will see the dtate’s resources going into shifting the chairs around on the upper decks of government. Like a badly run charity where all the donations are absorbed in administration, so is a coastal adaptation system where only small amounts of cash flow through to the places in which it is needed – the coast.
The concept of ‘bottom up’ does not infer that approaches to adaptation should be ad hoc or different. Consistent assessment strategies should be developed to be utilised across the State, but the application of these strategies should be fine grained and local.
Some work is progressing in this area:
- The Local Government Association’s Coastal Adaptation Decisions Pathways approach has been utilised in early adaptation planning at Adelaide Plains and Yorke Peninsula Councils
- CoastAdapt has provided alternative frameworks and thinking about adaptation. In particular, the use of a first, second and third-pass assessment approach provides flexibility in adaptation study.
- Integrated Coasts is currently adopting the best from both of these methods and developing coastal assessment processes that are flexible and local and currently being employed at Marion and Onkaparinga councils.
Use the precautionary principle for new development
This principle is in place now in the planning system and should be maintained and powers of direction strengthened so that new development is not implemented contrary to advice (as is currently occurring). Cadastral lines are like the walls of castles in feudal times, once in place they are almost impossible to shift. It is imperative that we do not draw new cadastral in places that may be at risk in 100-years' time, but also 200-years' time.
The application of this principle is not to prohibit replacement dwellings within existing settlements but rather the expansion of settlements into areas that may be under threat in the future. The application of this principle should also be considered in the current push to densify locations near open space, in the context of this paper, the coast.
Where possible provide (or allow) interim protection or accommodation strategies to cater for scenarios to 2050
Some locations around the state are set at very low elevations and scenario modelling suggests that many of these will not be viable by the end of the century if current projections are realised. Enforcing retreat, or abandoning these settlements is unlikely to be successful and such actions place councils and ratepayers in very difficult positions that are not easy to manage. The uncertainty in the projections suggest that an interim strategy is warranted in places that are unsustainable for the longer term (ie 2100):
- Where ever possible provide interim protection measures and strategies to cater for sea-flood scenarios projected for 2050 (a rise of 0.3 m). Providing a low height levee to cater for this scenario is generally inexpensive.
- Those that choose to remain in those locations will have 30 years or more to assess whether they wish to stay.
- Those that choose to buy into those areas should be made fully aware that protection is interim in nature and that there will be no further funds expended in raising the defences.
- In some locations, protection is not a viable option. However, the same principle could be applied in allowing people to demonstrate how they plan to accommodate increases in flooding. Councils should have the option to withdraw services once access roads and services became unviable.
There is a long-standing principle established in this state that public funding should not be expended to protect private property and this should be maintained. However, in the face of uncertainty, it appears to be an equitable principle to allow people to fund their own protection and accommodation measures, as long as public safety is managed, and no harm is propagated to other locations along the coast due to protection actions. This matter is already managed by legislation that ensures that all protection works require approval, and the Coast Protection Board has powers of direction.
Allow the market to factor in sea level rise over time
Whether we allow the market to factor in sea level rise is largely dependent on the type of actions we take now. If governments continue to protect, then communities will continue to expect that governments will protect. The proposal for protection/accommadation strategies outlined delivers a sense of equity. As a society we are not asking people to allow their properties to fall into the sea. If we allow the installation of interim measures, then we are also building in a time buffer in which to gather and assess more data.
However, it is not likely that we can protect all of our urban coastlines over time. And if the rate of sea level rise begins to escalates, and we are collecting local data from SEAFRAME gauges in local waters, then in time the market will factor in the risk. Over time the levees implemented for protection/accommadation strategies will become inadequate. We need to envisage policy and statutory instruments that provide certainty that protection works will not be upgraded.
But as a society, utilising this strategy we will provide the time for people to make their own decisions. As one CEO sardonically stated to me: ‘Sure, we will buy back the properties, but only when sea water is flowing through the front door’.
More rigorous warnings are provided to purchasers of properties in these locations.
There will be some exceptions. In places of high economic, community, and tourist value such as the metropolitan Adelaide coast, it is likely that protection will continue for a century or more, and private land owners who sit behind those protection systems will continue to be de facto beneficiaries.
Administration of coastal matters
In the opening of this paper I have sought to demonstrate that coastal impacts are felt differently from all other climate change impacts. Coastal impacts are felt locally, and not regionally. However, there are commonalities of these impacts that are felt along the entire state's coastline.
At the SA Coastal Conference in 2017, the proposal was put to attendees to consider the concept of an alliance of coastal councils. Essentially an alliance of coastal councils would provide a coordinated voice for local government around coastal management issues to the state and federal governments and to other bodies such as the Australian Seaside Councils, and various local government associations.
In particular, a coastal alliance of councils could lobby for funding, organise data collection such as the capture of digital models, and ensure that approaches to coastal adaptation are unified, resources and progress shared within the group.
Foster citizen science movements
The community are an incredible source of information to understand the history and prevailing coastal issues. In this modern era, digital phones are powerful recording instruments that are carried by nearly all citizens. This data could be collected and utilised. Most smaller communities around the state have progress associations. In larger locations, surf life saving clubs, and similar community entities exist. In all of these communities are people who would be willing to be involved in volunteer monitoring and data collection projects.
Encouraging citizen science will assist in moving the community away from the current emphasis of ‘predict and respond’ (and fear based) to ‘monitor and respond’ (action based).
CoastSnap beach monitoring is one such project currently operating in NSW.