By Giles Parkinson
For generations, professionals working in coastal and ocean engineering relied on what seemed to be the safe assumption that the natural environment – though subject to some variations – was statistically static.
About two decades ago, all that changed. NCCOE, the National Committee of Coastal and Ocean Engineering within Engineers Australia, was one of the first industry groups to recognise the potential impact of climate change on the work of its professionals. It concluded that the “proven rise” in carbon dioxide levels and the possibility of Earth being subject to a changing climate over engineering timescales has brought some aspects of this basis of design into question.
So, in 1991, NCCOE developed the first guideline for EA relating to climate change related to coastal and ocean engineering. Ongoing work by NCCOE has resulted in the recent 2012 release of three “ground-breaking” guidelines that have become a critical tool in creating practical responses to the effects of climate change on the country’s coastlines and built environment.
The first two documents relating to the impacts of climate change and to ecologically sensitive coastal engineering are updates to take into account the release of the Intergovernmental Panel on Climate Change Fourth Assessment report. The landmark new third publication, Climate Change Adaptation Guidelines in Coastal Management and Planning, was released in September last year.
Associate Professor Ron Cox, the Chair of the guidelines reference group, says Engineers Australia recognises that the changing climate is a key factor affecting coastal management practices in Australia.
“Maintaining Australia’s social, environmental and economic wellbeing requires a concerted effort to mitigate the effects of climate change, and it is here that the contribution of engineers is so crucial,” he says.
Cox was involved in the guidelines review from the beginning. The aim was to bring climate change considerations into professional practice, and the guidelines documents are a powerful initiative. “There is a lot of strength in professional associations putting out guideline documents,” he says, because of the potential implications if those guidelines are not followed. “We have been careful to balance technical content and such that the documents are not overly prescriptive. We’ve sought to have them provide information to assist engineers and decision makers make good judgments.”
As an example of the challenges that engineers now face, the rate of sea level rise has jumped from around 1.88 millimetres a year (or about 18 centimetres a century), to possibly four times that rate. That means that coastal structures built now have to consider the possibility that sea levels will rise 80 centimetres or more over the life of key infrastructure.
Indeed, Cox says that determining hazard lines for coastal planning purposes will affect all local government planning for current and future development on the coast, and will likely be the most tangible, and politically sensitive, example of how the guidelines are used.
And those judgments don’t just relate to the high-profile fights over waterfront development being played up and down the coast of Australia. A lot of media attention has been devoted to the impact on high-value beachside property and the court battles that have ensued. But Cox has noted that this barely scratches the surface: the real problems are the much larger number of properties in less visible canal estates and estuaries.
These may not be as high in property values, but there are more of them, by several orders of magnitude. And there is related infrastructure, such as underground power, communications, water, sewage and stormwater drains – all of which are very vulnerable to sea level changes. And there are political considerations.
“Documents are guidelines, not standards, so their use will have to be justified,” says Stephen Lees, the National Director, Sustainability, at the IPWEA.
However, he says the main difficulty facing local government professionals in coastal area of NSW and Queensland is that their state governments have withdrawn the sea level rise planning benchmarks. Still, knowledge about the science is constantly evolving, and the volumes will need to be further updated, particularly after the release of the latest IPCC reports in 2013/14.
To download the guidelines go to: www.engineersaustralia.org.au/coastal-ocean-engineering/publications