Over 55,000 people living on the flood plain in Sydney's West would be forced to evacuate, should a once-in-a-century flood engulf the area.
Inquiry findings into this year's flooding and response reveal 23,000 of those evacuating would be unable to flee the Hawkesbury-Nepean Valley, with current flood forecasting and road networking.
Recommendations in the report include a $2 billion investment into raising the Warragamba Dam wall.
