A proposal to build about 500 apartments on flood-liable land on the banks of the Bremer River in Ipswich, west of Brisbane, raises many questions about our continuing lack of respect for the potential severity of the consequences of flooding.

Development proponents, sometimes supported by councils, keep proposing to build on land that is not merely liable to occasional inundation but dangerously so. In this case, the site of the proposed development is adjacent to a shopping centre in which the proponent has a major stake, so the potential dwellings are likely seen as key to the success of the commercial precinct.

The problem is that developers are hard-wired, it seems, to utilise flood-liable land no matter the potential for severe consequences when, inevitably, floods strike.

Ipswich is one of many urban areas in Australia which has a history of disastrous, sometimes deadly flooding — think Brisbane, Rockhampton, Townsville, Lismore and Maitland among many others — and yet the pressure to build in areas with histories of severe flooding continues seemingly unabated. The memories of past floods, even quite recent ones, are seemingly pushed away from our decision-making. So is the evidence of potential future floods with a capacity for substantial property losses and large death tolls.

The site of LEDA Holdings’ proposed development in Ipswich, reported by the ABC on 2 October, is slated to take 23 “towers” of three to five storeys each. All dwellings in the towers would be above the reach of floods, meaning that none would take in floodwaters even in the biggest floods thought possible, but people will be “required” to evacuate if the Bureau of Meteorology forecasts a flood above the “major flood” threshold. Flooding to, or beyond, the “major flood” threshold is likely to be a not-infrequent occurrence. It might be seen, on a long-term average basis, every couple of years but occasionally it will occur a few times in a year.

The psychology of this should be of concern. People are to be “required” or “forced” to evacuate, even though their homes will not take in water. The likelihood is that many will simply refuse to leave, believing they will be safe above the floodwaters and can wait out the developing flood in situ. If there are several significant floods in quick succession that prove to create no more than short-term isolation to the occupants of the dwellings, their reluctance to evacuate will be more.

The evidence is that people not infrequently refuse to evacuate in the early stages of a flood, but then change their minds – putting at risk the emergency responders who then have to rescue them later. Resistance to leaving is likely to increase in they know the homes themselves will not take in water.

But what if a tower or towers catch fire? This is more common than thought, and it can be deadly when it happens. A case in North Dakota in 1996 is instructive: a fire caused by the ignition of a gas leak during a flood, which overtopped the town’s levees, engulfed several residential and commercial buildings in the Central Business District of Grand Forks. It crippled the town’s economy for several years. Then there was flooding in New York after Superstorm Sandy in 2012, when several dwellings caught fire and could not be attended by fire-fighters.

If people are trapped in burning buildings, the death tolls could be high whereas in most floods they are small or non-existent.

We are not taking account of the psychology that accompanies evacuation here. People easily latch onto justifications for not going: these intensify the natural wish not to leave the safe and familiar place that is home.

Our town planning sometimes comes up with dangerous schemes in these situations. At Maitland (New South Wales) in 2009, a report commissioned by the City Council recommended that new dwellings in the flood-liable inner city should have veranda railings at first-floor level suited to “docking” by rescue boats operated by the State Emergency Service. This, it was argued, would facilitate what was called “evacuation”. In fact, the proposal, if enacted, would likely have had the effect of encouraging the people to wait to be “rescued” rather than evacuating in their own vehicles. The report’s dangerous suggestion was favoured by the council. Fortunately, it was rejected by the state’s planning minister.

Indeed, it could be argued that the proposal discouraged evacuation independently and early in a flood event, using the time provided by flood warnings. Instead, residents would have been encouraged to wait until the water had cut off their escape by road. The term “deliberate entrapment” has been used in characterising policies likely to result in people becoming cut off. Such policies might actually increase the workload of the emergency services.

Some councils appear to be desperate to utilise land that is inherently dangerous only on rare occasions. They accept schemes of dubious worth, indeed schemes that might embody significant danger. This seems to be what is happening at Ipswich just as it happened at Maitland.

Many parts of Australia have serious flood problems. Yet, we often seem determined to intensify exposure to those problems by increasing the numbers placed at risk. Sometimes, of course, we go the other way, as at Grantham in Queensland where most of a small town was relocated to a flood-free site near the original settlement after a devastating flood in 2011. At Lismore, the council has, since the disastrous flood of 2022, bought more than 500 floodplain dwellings for demolition, reducing the numbers exposed.

We need to be careful that we don’t simply give the appearance of managing flood problems while actually intensifying the risk. We’d be wise to ensure that the schemes we propose take account of the difficult psychologies that surround evacuation. The Ipswich and Maitland cases fail in terms of these psychologies.

The views expressed in this article may or may not reflect those of Pearls and Irritations.