Breaking waves not likely to change Grantham flooding

A CIVIL engineer who reviewed a hydrology report prepared for the Grantham flood inquiry said any "breaking waves" were unlikely to substantially change the 2011 flood.

Several residents who experienced the disaster that killed 12 people have said they saw a wall of water during the flood.

The engineer, Stefan Szylkarski, reviewed firm SKM's hydrology report for the first inquiry and the report compiled by Dr John Macintosh for the current inquiry.

On Thursday, Mr Szylkarski told the inquiry his thoughts on whether modelling for "steep-fronted" waves might have an outcome on analysis of the flooding.

"There were two thoughts I had ... One was that the speed of the flood itself was that rapid that, leaving aside any potential quarry impacts, that you could have had a flood front travelling across the floodplain naturally that could have been sufficiently steep that you would see a breaking wave-type phenomena like you see on the beach," he said.

Mr Szylkarski said breaking waves were unlikely to substantially change the flood's behaviour.

Dr Macintosh finished giving evidence on Thursday.

On Wednesday, Dr Macintosh told the inquiry SKM's report misstated the nature of the Grantham quarry's breach.

He said while the report took into account the actual break, which was 300m to 400m long, SKM analysed a 50m breach as the only breach.

He said he could not fathom why SKM did not report upon it.

The public hearings continue on Friday.