Cracks in Three Gorges Dam do not pose safety risk, says expert

Cracks in the Three Gorges Dam - some as long as 10 metres - are normal and do not pose a safety risk, says an engineering professor.

The discovery has caused concern with the flood season approaching. A failure of the world's biggest dam would have catastrophic consequences downstream in the densely populated middle Yangtze valley.

The largest cracks are 0.3mm to 0.5mm wide and three metres deep, according to Gu Zhao-qi, a hydraulic engineering professor of Tsinghua University.

Professor Gu - a member of a team of experts invited by the central government to examine the structure - said the cracks were normal and did not pose a threat to the dam's safety.

He said the authorities had already spent about 10 million yuan (HK$9.4 million) repairing the problem.

'Of course, it's not good news. But it definitely won't affect the safety,' he said.

'Some say you can put a hand in the cracks. That's rubbish. These are surface cracks and are extremely narrow and shallow.