Council looks to new flood formula

QUEENSLAND councils are being urged to move away from one-in-100-year flood planning and focus more on likely future increases in rainfall.

The February 2008 flood left many Mackay streets and homes inundated, including Valetta Gardens, at Glenella. Picture: Rachel Hayes

QUEENSLAND councils are being urged to move away from one-in-100-year flood planning and focus more on likely future increases in rainfall intensity brought about by climate change.

Mackay Regional Council will consider the recommendation, from the State Government and Local Government Association of Queensland (LGAQ), but has already moved towards increasing predicted rainfall intensity when developing flood studies.

Director of development services Peter Cardiff said council had already taken climate change into account when developing flood studies.

“As the study was only recently released council will be considering the recommendation in its entirety,” he said.

“In recent flood studies carried out by council, council has taken into account various climate change scenarios. As part of The Gooseponds Flood Study, developed in 2009, council modelled a potential rainfall intensity increase of 20 per cent and 30 per cent for 100 years, which are above the requirements of recommendation two.

“Council is in the process of developing new flood and inundation mapping and, as part of this process, will review the recommendations of the Queensland Government and the LGAQ.”

Climate Change and Sustainability Minister Kate Jones, who released the joint State Government and LGAQ study, said the Inland Flooding Study recommended a new formula for councils when factoring flood risk into planning decisions.

“Flooding cost state and local governments more than $200 million in damage to infrastructure following heavy rain across north-west Queensland and in Mackay in 2009,” Ms Jones said.

“That was followed by extensive flooding in March this year in south-west Queensland and more heavy rains fell in October in the south-east.

“Using Gayndah as a case study, we’ve provided a benchmark to assess increased flood risk together with examples of how local governments can better deal with that risk,” Ms Jones said.

The Inland Flood Study project involved collaboration with local government, scientists and flood specialists from leading organisations including the Bureau of Meteorology, CSIRO, the National Climate Change Adaptation Research Facility, the Walker Institute for Climate System Research and the University of Queensland.

Officers from the departments of Environment and Resource Management and Infrastructure and Planning will work with councils on key study findings.

Originally published as Council looks to new flood formula