As fire has driven this evolution, allowing nature to bend rather than break, the Southern Oscillation Index which results in the El Niño and La Niña cycles, drives our own efforts to adapt to climate variations and create a more resilient future for our cities. By harnessing technology and learning from other sectors we can evolve tools and strategies that allow us to resist the whole gamut of challenges Australia faces.
Flash flooding: a matter of life and deathThe catchment area around Parramatta, New South Wales, is known for a propensity towards flash flooding. The natural catchment combines with the large impervious surface area and little in the way of surrounding pasture or bush to deliver a very high risk of flooding in the central business district. River levels can reach six or seven metres above normal levels with a flood response time of just 90 minutes, resulting in the potential for huge damage to property and threat to life.
Parramatta does therefore offer the ideal proving area for ground-breaking use of early warning technology. Working with Nelen & Schuurmans we created, a tool to provide Parramatta council and the state emergency services with early warning of flash flood events. The Parramatta system uses the extremely efficient 3Di flood model, combined with Rainfields-3 forecasting and “cloud”-based computing to empower decisions around warning or evacuation procedures. Tested in the flooding of February 2020 the tool isbeing held up as an example of the potential of digital technology to enhance urban flood resilience.
Joined up thinking for fire and waterOne of the keys to the success of the FloodSmart tool is the creation of uniformity across measuring systems and gauges around the catchment area. Historically these gauges have fallen under multiple ownership and have used different datums and reporting systems. By coordinating this data gathering into a single format we can feed real-time information into the flood model and allow users to compare real and predicted water levels and continually improve the accuracy of the reporting.
This coordination of effort is something we are hoping to take forward into supporting resilience across all the natural challenges we face.
This summer the bushfires in Australia have filled headlines around the world. For the first time an app, Fires Near Me, has been available to the public, which empowers individuals to understand their personal risk and take appropriate action – I used it myself to plan a safe route for our summer holiday road trip.
The app currently only provides real-time data around fires, but this should be seen as the first step in the evolution of building a predictive tool. By joining forces with the emergency services and other experts in the spread of fire, there’s potential to use the same sort of modelling technology as in the FloodSmart tool to predict the event and spread of wildfires. Doing so could save lives and avoid the additional burden on emergency services created by a lack of awareness of fire risk.
Mitigating urban water challengesAustralia faces the same issues around urbanisation that affect cities elsewhere in the world. Population increase, hard, impervious surfaces and planning issues place the cities at increasing risk of water-related crisis.
However, Australia’s size and lower population density mean that traditional structural mitigation tools can be ineffective or prohibitively expensive. As in most cases, prevention is better than cure and local governments are working to discourage development on flood plains. In cases where this is unavoidable, measures concerning flood levels, electrical outputs and building materials are being put in place to mitigate damage in the event of flooding.
Traditional levees, drainage channels or other structural defences do have their place – such as in the South Rockhampton levee project we’ve been involved in peer reviewing. It’s evident that lessons are being learnt from around the world to improve their performance. In addition, stakeholder engagement with residents and businesses in the affected areas will ensure better awareness of the potential threat – after all, there’ll always be a bigger flood.
How to predict the unpredictable?At the opposite end of the spectrum to extreme rainfall and flooding, drought is never far from our minds in Australia. The start of the prolonged dry periods is notoriously difficult to predict; and the end, even harder. Sustainable water use is key to alleviating shortages, but the issue is extremely complex, with roots that go back to the actions of the first European settlers which continue to define how the land and resources are managed. Recent measures to mitigate drought have included lowering of outfall levels to allow additional water extraction from existing dams, transfer pipelines to better manage existing water resources, and additional dam planning and redesign, including embankment raising to add volume.
However, the complexities and depth of feeling around the environmental flow requirements was seen in the protests that followed the publication of the Murray Darling Catchment plan in December 2019.
Building better resilience, whether that’s to flood, fire or drought, will be an evolutionary process. Using lessons learnt and tools developed in one sector to improve resilience in another will speed this process and ultimately achieve a far more cohesive approach.