Have a look at these before and after photos of Brisbane during the floods of 2011.

The special thing about these photos is the technology, which uses high-resolution aerial photos taken over various suburbs and the CBD which reveals the scale of the devastation.

There is a black line in each photo, which you hover over using your mouse, and then you drag the line to the left of the photo, revealing the extent of the flood – just amazing.

Today we have so much information and photography available for such events.

This is part one of an ABC News special presentation.

Before and after photos of Queensland floods in 2011.

You can also view part two:

Part two