Where is Queensland up to with flood management?

It is now more than three years since Queensland's disastrous flood summer of 2010-11. A few short weeks saw three quarters of the state declared a disaster area, many towns flooded, thousands of houses taking in water and some being destroyed, and large numbers of people having to evacuate. The communities of the Condamine-Balonne and Lockyer valleys and Ipswich and Brisbane were especially grievously affected. Now, with various proposals devised, under consideration or being implemented, it is possible to see what the state might do to manage flooding in the future.

First, some context. The summer of 2010-11 was actually just the worst of a period of four years of unusually frequent and severe floods which affected virtually all parts of the state. Some places were flooded repeatedly. The previous summer had also been a bad one for flooding, and so were the two that followed. The mayhem seemed to come to an end after ex-Tropical Cyclone Oswald brought record flood heights to Bundaberg and other Burnett River communities in January 2013.

Flood-rich periods can create the momentum for action to manage the effects of flooding. The experience of flood after damaging flood focuses community and governmental minds to a degree that single floods, on individual rivers, cannot. Repeated, widespread and severe flooding creates situations from which comprehensive, far-reaching action can be instituted.

Have minds been focused in Queensland? Is the state seizing the opportunity to better manage this most expensive and disruptive of natural hazards?

The answer is a mixed one. Decisions are being made, but the effort being mounted appears too narrowly based to allow floods to be managed as well as should be possible. An historic opportunity is about to be missed.

About a dozen towns have investigated the building of levees and some like St George and Roma are close to finalising levee-building projects talked about for years. Others have levees planned, but in others again levees will probably not be part of the strategy. Some flood-prone urban areas, like Gympie, Ipswich and Brisbane, have sites that are topographically or otherwise inappropriate for levees to be a significant part of the effort.

On the Brisbane River, the flood mitigation role of Wivenhoe Dam has been much scrutinised and new operating procedures adopted. Henceforth, the dam will not be allowed to fill to the degree that occurred in early 2011. Releases will begin at lower dam levels, with some negative consequences as far as prolonged rural inundation and the isolation of communities upstream of Brisbane are concerned but with the benefit of reduced peak flood heights in built-up areas.

Beyond that, the state government has flagged its intention to build flood mitigation capacity in the form of new dams within the Brisbane River catchment, and to raise the wall of Wivenhoe Dam so more floodwaters can be impounded. Eight potential dam sites are under investigation.

New dams carry the potential to reduce peak flood heights both in Ipswich and Brisbane. But it will be all too easy to exaggerate the benefit, because the flood height reductions will probably be small. It is likely that given similar rainfalls to those of early 2011 they will save only a small minority of the buildings that experienced over-floor inundation in Brisbane on that occasion.

Most of the proposed dam sites are in the headwaters of the river system and will command only small proportions of the catchment. Moreover the economics of dam construction are unlikely to allow them all to be built.

Over time low sections of the Bruce Highway, the state's main transport artery, will be raised. Communities will be cut off less frequently and disruption to the economy will be reduced.

But dams, levees and the raising of roads will not render flood prone areas immune . That is important to recognise, and it is to be hoped that there is no repeat of the situation that followed the building of Wivenhoe from 1977 to 1985. Then, the Bjelke-Petersen government trumpeted the dam as the 'solution' to Brisbane's flood woes.

The result was that residential and other development was encouraged on the floodplain. Brisbane's vulnerability to flooding was actually increased, not lessened. The 2011 flood, which peaked at the Brisbane Post Office gauge at a level roughly a metre below that reached in 1974, actually saw more properties inundated than had the earlier event. Between the two floods, the dam became a reason to increase the vulnerability of the community. The financial costs of the 2011 flood in Brisbane, after adjusting for inflation, were probably twice those of the 1974 event.

A paradox arose. A flood mitigation measure had the effect of intensifying the flood problem.

Therein lies a lesson. The core of the flood problem lies in our use of land. Every generation of Queenslanders has made it worse by building more dwellings, business premises and public facilities on floodplains. No generation has recognised, let alone acted upon, the consequences of this fundamental truth. And the cost goes up and up. And then up some more.

Now, what Queensland looks proposes to do is to treat the problem of flooding as one of water management rather than land and community management. Thus it will fight floods by building dams and levees and raising roads. We seem incapable of modifying communities to make it easier for them to live with floods. We are using one set of strategies, but ignoring another and more fundamental one as we have for decades.

Queensland appears unlikely to make a significant effort to restrict urban development from places which are guaranteed to flood periodically. Nor is it probable, judging from what has been announced so far, that the state will invest in measures like house-raising or buying back properties which have histories of frequent inundation. Interestingly, in 2006 Campbell Newman as Lord Mayor of Brisbane sought state government help with just these measures to alleviate the problems of flooding on Brisbane's creeks. He was unsuccessful.

And there has been little discussion about increasing the ability of people who live in flood-liable areas to deal with flooding. Specifically, these people need to better understand the forecast flood heights at which their properties will be affected and in preparing for which they should take action to protect items of value. Clearly, this understanding is lacking in flood liable communities at present.

Too often residents do nothing until the floodwaters are upon them, by which time the protection of items of monetary and sentimental value is difficult. The evidence lies in the piles of household and commercial items on the footpaths of towns and cities after floods, and later in hikes in property insurance premiums. It is clear that flood warnings have not sufficiently encouraged property-saving actions like raising items or moving them to higher ground. Strangely, this is little recognised in post-flood enquiries. We need to help floodplain residents to deal with the inevitability of flooding by responding better as floods develop.

And we should be preventing the problem from becoming worse (for example by prohibiting all but unavoidable building on floodplains) while at the same time instituting programmes by which some at least of the accumulated legacy of past developmental follies is reduced by strategies of 'planned retreat' from floodplains. We will never achieve that in totality, of course: it would be prohibitively expensive. But we could remove buildings from the worst affected locations.

But instead of tackling the problem broadly with a wide range of measures, Queensland aims to employ partial, engineering-based works. Controlling floodwater will be the principal method. A cynic might say that dams are more visible than effective, and that they are beloved of governments (and indeed communities) because of that very visibility. The reductions they bring to flood heights are smaller than might be supposed, determining the best water release strategies from the small number of gated dams is difficult, and wherever dams are built the rains that produce flooding can fall downstream of them. Much of Brisbane's 2011 flood came from rain that fell below Wivenhoe Dam and over the tributary catchments drained by the unregulated Bremer River and Lockyer, Warrill and Oxley creeks.

Reducing floodplain development, of course, carries political risks because it limits how landowners can utilise their land. And educating people on how to protect their interests as floods approach is less tangible than building dams and levees.

Brisbane Lord Mayor Graham Quirk has recognised the difficulty of changing the rules about building on floodplains. People who own land have rights, he notes. So they do, but those rights are producing big increases in the cost to the public purse, both in handouts to flood victims who have exercised their rights and in the repair and replacement of infrastructural assets. How far should respect for property rights be allowed to go on intensifying community vulnerability and increasing the costs of dealing with it?

Usage rights in relation to land are not absolute, and decisions of governments can disadvantage some landowners. The evolution of modern town planning, indeed, prevented some owners from using their land in certain ways ─ but important public benefits accrued including the separation of residences from noxious industry. Meanwhile the Queensland Planning and Environment Court periodically refuses owners' land development proposals on public interest grounds, and over time regulations on development on floodplains have tended to become more stringent.

Society's interests would surely be advanced if we took strong steps to manage the escalating costs of flooding. In bad years like 2010-11, these are now measured in several billions of dollars in Queensland. Monetary levies are struck to pay for restoration tasks, development projects are postponed because money has to be diverted to repair functions, and insurance premiums rise dramatically. The spectre is raised of even greater disaster when people who can no longer afford to insure are struck by flooding.

Queensland is allowing the flood problem to grow while making only piecemeal attempts to manage it. Sooner or later, we will have to take a stronger approach: the costs of not doing so will mandate it. But the longer we take to make the change the costlier it will be.

We would be best served by recognising that flood management is not just a matter of building structures, but something larger. It is the management, indeed, of communities in ways that allow people to live better with flooding. Community development should seek to reduce vulnerability to disaster, not allow the quantum of vulnerability to grow while tackling it only at the margins.

Sadly, we seem incapable of recognising that the longer term might see flooding, already the most dollar-costly of all the natural perils in Australia, get more serious. Scientists predict that severe floods are likely to become more frequent in Australia. There is a current problem, then, and potentially an even more worrying future one.

Queensland's flood management paradigm needs fundamental modification. Future generations, contemplating the impacts of the floods they will inevitably have experienced (and here we beg the question as to whether flooding will have become more frequent or severe) will be justified in concluding that we failed to make the most of the opportunity that the floods of 2009-13 presented.

It is possible to observe the debate on climate change and wonder whether the world will ever institute effective measures to tackle the risks it poses. It is also possible to look at flooding as both a major problem in its own right in Queensland and as a subset of that even bigger problem and to ask whether we have the wit to address it comprehensively. So far we have preferred to allow it to grow ever larger and to be left largely for future generations to manage.

Just like the wider world in managing climate change.