Flood plan may stop history repeating
	Second wave: A repeat of Mackay's devastating 1918 floods may be avoided through CRES research
By Julian Lee In 1918 the North Queensland town of Mackay was all but destroyed by a cyclone-induced five-metre flood and an ANU scientist claims it is a sitting duck for a repeat - but he is doing something about it. Andre Zerger of CRES is developing a system that will minimise the impact of another flood. "We don't have the records to accurately determine when a similar event could happen again, it could happen at any time," Mr Zerger said. He has used a computer-based geographical information system (GIS) to link maps of the terrain with council information on roads and buildings. With this system, Mr Zerger can see the effect that different flood heights would have on the area. "GIS assists greatly in understanding and visualising complex data sets. Being able to see the flooding trends will enable emergency managers to plan escape routes with greater speed and confidence," he said. Since power is likely to be erratic and computers unreliable during an emergency, Mr Zerger has created a "look-up table" of pre-drawn maps to provide an instant record of possible escape routes. Before the next cyclone season begins in January, Mr Zerger intends to test the look-up table with emergency managers to see how useful they find it. If it does aid decision-making, then he intends to develop guidelines so that it can be extended to cover other flood-risk communities on the north Australian coast. "What makes Queensland particularly vulnerable is the lack of government planning regulations to restrict the type of building that can be built in flood-prone areas," Mr Zerger said. Queensland - dubbed the "new California" due to its having some of the highest urbanisation rates in the world - has seen a proliferation of ground-floor, concrete-slab buildings. Mr Zerger believes community awareness of the dangers of flood in Mackay has diminished in the 70 years since the last storm tide. This lack of awareness has also extended to the reasons for building traditional, high-set buildings. Mackay today has one of the highest tidal ranges in Australia, at seven metres, and has almost 4,000 residential properties built on the flood-prone coastal plains. "We are highly certain that a flood similar to the 1918 flood would result in over a quarter of the buildings in Mackay flooded to a depth of one metre, at an estimated cost of up to $150 million," Mr Zerger said. While he cannot answer what it is about human nature that causes people to repeat past follies, Mr Zerger hopes that seeing the results from his model will highlight the dangers of living in risk-prone areas. "I hope that planners would do a natural hazards risk analysis before deciding to build, then zone and build appropriately," Mr Zerger said.