Lismore flooding: Devastating before and after photos show extent of emergency

While the devastating floods affecting the city of Lismore have produced unenviable records in terms of rainfall, the sheer level of destruction can be hard to quantify for those attempting to process the statistics.

More than 700mm of rain fell in a 30-hour window, while the Wilsons River rose to 14.37m – more than 2m higher than the previous record set nearly 70 years ago.

And while images of young families clambering on roofs have shocked Australians across the country, it's before and after shots of the northern NSW community that truly paint a picture of the terrifying conditions residents are facing.

In the city centre, Magellan Street is completely submerged, with the first-floor balconies of the Lismore City Motel barely visible.

Further along Magellan Street, the Vinnies store, along with a row of shops, has completely disappeared under the water.

The city's McDonald's offers a remarkable indicator of how high the water has risen, with the outlet's street sign largely engulfed.

Ballina Road, one of the city's main arteries, is completely submerged and is pictured with several rescue boats on it. The water level at the overhanging traffic lights are an indicator of how high the water has risen.

Former Lismore resident James O'Brien shared a striking image of rescue efforts on the Ballina Street Bridge, with SES teams swamped in water. A before photo shows the height of the bridge at normal water levels.

In a blog post, he said his sister Pat, who experienced the devastating 1954 floods, "found herself sitting on a chair on the kitchen benchtop, with water up to her chest".

"Never in her wildest dreams did she think she would ever be in that position again [after 1954]," he said.

NSW SES has said the floods are worse than anticipated, with more than 34,000 people ordered to evacuate their homes.

Ballina Mayor Sharon Cadwallader said the flood was a one-in-500-year event, and on Tuesday morning Ballina was also being evacuated.

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