Three major floods, four reviews, but still lessons to learn

By Karen Hussey and Jamie Pittock

The last few years provided plenty of data to help us reform our approach to floods. With devastating flooding in Queensland and Victoria in 2011 and 2013, we should have learned a great deal about which approaches to flood mitigation work and which are less effective. A review of four recent Australian studies of mitigation and adaptation, and a comparison to overseas recommendations, shows we are lagging behind international practises in a number of important areas.

The Australian approach

We looked at four recent reviews of flood mitigation and adaptation in Australia: the Queensland Floods Commission of Inquiry, Brisbane City Council’s Flood Response Review, the Victorian Parliament’s Inquiry into Flood Mitigation Infrastructure in Victoria and the Victorian Floods Review.

These reviews varied greatly in scope, and all produced a comprehensive list of considered and much-needed recommendations to improve Australia’s resilience to floods in the future. But one surprising fact was none of them dealt with future climate impacts. Some didn’t even mention climate change. Government reviews are expensive, but the cost is justified if they identify reforms which improve society. By not taking into account the risk of future climate change and its exacerbation of flood risk, governments are missing an opportunity to include those risks in the current reform agenda.

Australian governments take the attitude that we can re-make flooded communities exactly as they were before. As soon as a disaster is declared, federal funds are made available to rebuild to “pre-disaster” conditions. There is little or no expectation that infrastructure should be made more resistant to flood damage. In the United States 15% of federal funding is allocated for “betterment”; here there are virtually no resources to plan for, relocate or strengthen flood prone infrastructure to make it more resilient.

The Australian approach to “flood proofing” communities is to build levees. Levees essentially take the same body of water and squeeze it into a smaller space. They don’t encourage evaporation, and they push water to higher levels. They work well in small floods, and under those conditions are very effective at protecting communities. But in recent years we’ve seen bigger floods, and these are likely to get worse. In bigger floods the levees are often overcome, and the potential for serious damage becomes much greater than it would be without them.

“Non-structural” or “ecosystem” approaches to flood mitigation work much better than structural measures like levees. But in Australia, we rarely consider these types of measures.

International ideas

Internationally, the story is very different.

In our research we also looked at flood reforms in the USA, China and the Netherlands. In all three, climate change was a driving force behind their significant recommended reforms.

All of these countries recognise they have reached the limit of what levee banks can usefully achieve. Instead, they have instigated a range of reforms built around the concept of ecosystem management.

The first of these is “making room for the river”. The river channel is widened or deepened to allow more water to flow through while remaining within its bounds. Flooding of surrounding areas is reduced.

Since its devastating floods in the 1990s, China has been restoring flood plains, buying land around river channels and relocating people to higher ground. This has happened most famously as part of the Three Gorges Dam development, which attracted a lot of negative media coverage. But we’re finding that years after relocation, people have shifted to crops that are less prone to flood damage which, combined with being on higher ground, means they’re hit by floods less often, and they’re better prepared to deal with those that come along.

All three countries have changed the way they manage their floodways. Where cities and towns are vulnerable, the government diverts the river into agricultural land around the town. In a flood season the city is protected and agricultural areas are flooded instead. The farming communities are paid by the government to forgo income during floods, but still use the land at all other times. Australian research has shown that for graziers, more frequent flooding can actually improve farm incomes.

What could Australia learn?

Australia has dabbled in ecosystem approaches and relocation, but often in an ad-hoc way.

Critics of ecosystem approaches point out that it’s all very well to deepen a river upstream, but if you don’t deal with the towns downstream, flooding there will be much worse. For ecosystem approaches to work, management and planning have to be undertaken on a much larger scale.

In the southern Murray-Darling Basin, the government proposes removing constraints such as bridges and dams to allow for bigger peak environmental flows (that is, floods). This work is very promising, but what about the rest of the Murray-Darling Basin and, indeed, the rest of the country?

Currently, we don’t have coordination and integration across jurisdictions within and between states. But rivers don’t respect administrative boundaries: when you’re developing ecosystem approaches, you have to use the natural environment as your point of reference.

There have also been a few examples of relocating communities: Grantham and Gundagai being the most notable. This relocation is expensive, but as floods become bigger and more frequent it’s something Australia needs to do more often. The financial and social costs of retaining and rebuilding flood prone towns over and over and over again will soon add up. When the taxpayer is picking up the bill, at some point you must decide whether rebuilding is an economically viable solution, or whether in some situations relocation is the more sensible approach.

And of course we must take account of future climate risks. While none of these reviews seriously studied those risks, change is happening elsewhere. The Australian Rainfall and Runoff Guide is one of the most important national reference guides, and is used by planners and builders to help them allow for floods. It’s currently under review, and future versions will take account of the effects of both natural and anthropogenic climate change. This attitude should spread to all flood reform.

Karen Hussey receives funding from the National Climate Change Adaptation Research Facility.

Jamie Pittock receives funding from the National Climate Change Adaptation Research Facility.

This article was originally published at The Conversation.
Read the original article.

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Responding To Extreme Weather Events

Australia, particularly Queensland, has recently been struck by a sequence of extreme weather events. Cyclone Yasi and the floods of December 2010 / January 2011 saw more than 75% of Queensland officially declared a disaster zone. The impact on infrastructure and homes was devastating but the scale of the tragedy became that much more apparent as news of human fatalities was relayed by Queensland Premier, Anna Bligh.

Sustainable urban development is a useful concept in considering opportunities to alleviate the impact of extreme weather events, and extreme floods in particular. Sustainable urban development provides a framework focused on creating urban communities where both the current and future needs of residents are met. There are two important principles—resilience and connectivity—that underpin sustainable urban development.

By defining the risks associated with potential extreme events and translating those risks into planning and design solutions urban planners attempt to increase an urban feature’s capacity to absorb change. This capacity, otherwise known as its resilience, allows it to persist in the face of the change and thereby improves its sustainability.

The elements of the physical, biological, social and economic system in which we operate are fundamentally connected. This interconnectivity is relevant in all systems, but particularly in urban environments, where the proximity of the component elements and the frequency of interactions are higher.

These high-level principles point to four areas of response available to help manage the impact of extreme flood events before they occur. Looking particularly at existing and future developments and structures, this paper will discuss the management imperatives needed to ensure our urban fabric is planned, designed and constructed to not only respond proactively to extreme weather events and the ‘human contribution’, but also addresses the need to remove the barriers to decision making when related to complex, interacting systems.

Mr Matt Coetzee, Development Manager – Community Development, Aurecon

Healthy Cities: 4th Making Cities Liveable Conference
Wednesday 27th to Friday 29th July  2011
Venue: The Outrigger Little Hastings Street Resort & Spa NOOSA, Queensland

Sustainable Urban Development: Responding to Extreme Events

Australia, particularly Queensland, has recently been struck by a sequence of extreme weather events. Cyclone Yasi and the floods of December 2010 / January 2011 saw more than 75% of Queensland officially declared a disaster zone. The impact on infrastructure and homes was devastating but the scale of the tragedy became that much more apparent as news of human fatalities was relayed by Queensland Premier, Anna Bligh.

Sustainable urban development is a useful concept in considering opportunities to alleviate the impact of extreme weather events, and extreme floods in particular. Sustainable urban development provides a framework focused on creating urban communities where both the current and future needs of residents are met. There are two important principles—resilience and connectivity—that underpin sustainable urban development.

By defining the risks associated with potential extreme events and translating those risks into planning and design solutions urban planners attempt to increase an urban feature’s capacity to absorb change. This capacity, otherwise known as its resilience, allows it to persist in the face of the change and thereby improves its sustainability.

The elements of the physical, biological, social and economic system in which we operate are fundamentally connected. This interconnectivity is relevant in all systems, but particularly in urban environments, where the proximity of the component elements and the frequency of interactions are higher.

These high-level principles point to four areas of response available to help manage the impact of extreme flood events before they occur. Looking particularly at existing and future developments and structures, this paper will discuss the management imperatives needed to ensure our urban fabric is planned, designed and constructed to not only respond proactively to extreme weather events and the ‘human contribution’, but also addresses the need to remove the barriers to decision making when related to complex, interacting systems.

Mr  Matt  Coetzee,  Development Manager – Community Development  Aurecon

Healthy Cities: 4th Making Cities Liveable Conference – Wednesday 27th to Friday 29th July  2011 Noosa Qld, Australia

Urban Flooding Policy – What can we learn from the UK?

Many areas in Australia have recently faced major flooding following a long drought period. Whilst policies are in place to manage the impact of flooding including achieving appropriate flood immunity levels for development and minimising the impact of development on flooding – it is evident that many areas are at risk of flood inundation and its associated damage to homes, businesses and infrastructure.

The United Kingdom has also faced these issues with 1 in 6 (5.2 million) properties currently assessed to be at risk of flooding. A number of large flood events over the past 12 years led to a significant rethink in the approach to managing flood risk in the UK. One of the major changes relates to the improved links between development planning and flood risk management.

There was a renewed recognition that inappropriate spatial development has the potential to provide a triple threat to flooding by adversely affect flood sources (through increased runoff), flood pathways (through interference with defence and flowpaths) and receptors (by increasing the loss and damage caused by flooding). The Planning Policy Statement 25 on development and flood risk, has now evolved from an earlier planning guidance to prevent inappropriate development with respect to flood risk. At all stages of the development planning process, this planning document requires planning authorities to apply a risk-based sequential approach to the zoning and allocation of development land to ensure developments are placed at locations with as low a risk as possible depending on their potential vulnerability.

This paper will describe how planning policy and its implementation in the UK has evolved. Case studies will be used to illustrate particular aspects and draw out lessons learnt from its implementation. Potential refinement of Queensland policy to incorporate changes will be considered with discussion regarding the implications of such changes.

Miss Trinity Graham 
Principal Water Engineer
Aurecon 

Healthy Cities: Making Cities Liveable Conference 2011

Prestigious Waterfront Homes Now in No-Go Zones

Some areas of Queensland are so flood-prone they should never have been built on and should be declared no-go zones, according to an international disaster expert, Professor Ed Blakely, who says extreme weather events are becoming increasingly more frequent and far more devastating. While the Institute for Sustainable Development’s Professor George Earl says the flooding disaster underlines the need for adequate infrastructure to deal with the effects of climate change. “Areas which were prestigious in previous generations now are those very properties which are at most risk because of climate change and rising tidal waters”.

Professor Ed Blakely will keynote at the Healthy Cities Conference in Noosa in June 2011

Karen Kissane in The Age (15 January 2011):

An economist on Queensland’s Gold Coast says the Brisbane floods have highlighted the challenges that can confront waterfront property owners. Riverfront homes were among the thousands of properties inundated in south-east Queensland last week.  Around 180 real estate professionals from around the world are discussing the impact of climate change on property developments at a conference at Bond University this week.

The director of the Institute for Sustainable Development at Bond University, Professor George Earl, says the disaster underlines the need for adequate infrastructure to deal with the effects of climate change. “Areas which were prestigious in previous generations now are those very properties which are at most risk because of climate change and rising tidal waters etc,” he said. “I don’t think they will become less desirable or even less valuable – I think what it will do is heighten the emphasis on sustainable infrastructure. “There are some areas which have gone under in the last few days up in Brisbane which are quite OK to be built on.

“It is just that in fact we have to understand the infrastructure that’s needed not to protect just them, but the city in general has to be upgraded. “We have to do more significant work in terms of understanding the issues of climate change on real estate.” However, he says last week’s floods will not cause long-term damage to Brisbane property values. Professor Earl says the damage will not make south-east Queensland any less desirable to home-buyers or dramatically reduce prices. “In the short-term, it will probably stagnate them and probably make them go back somewhat,” he said. “But I think that as we start handling better the issues of climate change and real estate and urban planning, Brisbane and the Gold Coast will still be beautiful places to live.

By Charmaine Kane for ABC (17 January 2011):