Modelling technique assesses the impact of dam collapse

Chinese and Australian scientists have developed modelling techniques to help understand the full impact of flooding that occurs when dams collapse.

The work by China’s Satellite Surveying and Mapping Application Centre and Australia’s Commonwealth Scientific and Industrial Research Organisation (CSIRO) will help disaster-management authorities better understand the full impact of the catastrophic flooding.

The team modelled the effects of a failure of the massive Geheyan Dam in China’s Hubei province. They simulated the impact of flooding on the surrounding region and its infrastructure if the dam suddenly released its 3.12 billion cubic metres of water.

Dam failure is of particular concern in China because many of the country’s 70,000 dams are in regions prone to earthquakes.

’We modelled six different dam-failure scenarios,’ said CSIRO computational scientist, Dr Mahesh Prakash. ’Our simulations show where the water would go, how fast it would reach important infrastructure such as power stations and the extent of inundation in major townships downstream.’

CSIRO’s approach combines data that changes over time — the water flow — with static landscape data from a Geographic Information System to show how infrastructure will be affected.

’The modelling technique we developed for this work is really powerful,’ Dr Prakash said. ’It gives us very realistic water simulations, including difficult-to-model behaviours such as wave motion, fragmentation and splashing.’

The team at CSIRO used the same technique and software to model other catastrophic geophysical flow events such as tsunamis, floods, storm surges, as well as landslides and volcanoes. The technique was tested by modelling the 1928 St Francis dam break in California, which produced a very accurate simulation of what happened in real life.

The project is funded under the Australia-China Environment Development Partnership by the Australian Agency for International Development.