![Lismore's CBD is flooded after the Wilsons River breached its banks early on Friday.](/web/20170520225409im_/http://www.smh.com.au/content/dam/images/g/v/a/h/q/j/image.related.wideLandscape.620x349.gvag39.11u395.png/1490959777060.jpg)
Sirens sound in Lismore as levee cracks and city floods
Thousands have abandoned their homes in northern NSW and hundreds of people rescued from floodwaters as the remnants of ex-tropical cyclone Debbie bore down, dumping a staggering amount of rain on the region.