Timeline of Lismore flood shows horrifying speed of Wilsons River rise

The State Emergency Service has defended its timing of Lismore’s evacuation after river level predictions “changed drastically” in the hours before disaster struck. See the timeline.

A timeline of the Lismore floods and the warning issued has given some context to residents’ shock at how quickly flood water rose and how hard it was for the authorities to deal with drastically changing predictions a few hours before the disaster.

The State Emergency Service says it relied on Bureau of Meteorology information before making flood warnings.

Lismore residents were shocked by the speed at which Wilsons River rose a fortnight ago, pointing out that they never expected it to be like this.

Most were glued to the emergency updates but were convinced that the flooding couldn’t be much worse than the 2017 floods (11.6m) or perhaps the 1974 event (12.5m).

Lismore residents were ordered to evacuate at 9.30pm on February 27 but predictions of the river level and levee overtopping were consistently being revised into the early hours of the morning.

When questioned about evacuation timing, a State Emergency Service spokesman said the organisation was “heavily reliant on weather advice and observations provided by the Bureau of Meteorology” and said the nature of the weather meant predictions “changed drastically”.

“The record-breaking flood that occurred in Lismore was like nothing that had been experienced before,” the spokesman said.

“It came much quicker and more intensely than was forecasted.”

A Bureau of Meteorology spokesman said the organisation forecasted the risk of heavy rainfall over northern NSW and flood warnings “many days in advance”.

Asked if the bureau’s predictions of the river levels and time of the levee overtopping on Monday was due to incorrect analysis, the spokesman said the organisation continued to update its forecasts and described the event as a “rapidly evolving and dynamic weather system”.

Within the space of 12 hours Lismore residents went from expecting a flood level of 11.5m to record breaking river rises. Picture: Toby Zerna

“A severe weather warning for heavy rainfall and damaging winds for northeast New South Wales was issued on the morning of Saturday, 26 February,” the spokesman said.

“This was followed on Saturday afternoon by a warning for moderate to major flooding, expected from overnight Sunday into Monday.

“Initial forecasts were made for river heights and the bureau made it clear that river rises were possible with further heavy rain.”

Just after 5pm on Sunday, February 27, as businesses and residents were moving stock and valuables to higher ground, the State Emergency Service issued a flood evacuation warning putting the town on standby to move to safer ground.

The Wilsons River was expected to reach 10.6m at some point on Monday but across the next 12 hours, those predictions would constantly be revised.

A South Lismore home was torn to shreds as many residents of the area refused evacuation because they didn’t expect the flood level to reach so high. Picture: Nicholas Rupolo

Three and a half hours after they predicted the level would reach 10.6m a fresh alert said it could reach 11.5m and that the levee would overtop at 6am on Monday, February 28.

At 1am on Monday the river levels were revised again, this time with a prediction of 12.5m and the levee overtopping at 5am instead of 6am.

The strength of the rain wiped those predictions away with the levee overtopping just after 3am and renewed predictions of the Wilson River to reach 13.5m.

Lismore was entering life-threatening flood territory that was soon to become record-breaking.

The revised prediction of a 13.5m flood was to go under as well with the aftermath revealing the flood waters reached close to 14.5m, confirming the event as Lismore’s worst flood on record.