NSW Sutherland Shire flood zones

What's the go with the flood zones in the Sutherland Shire according to the flood mapping software https://maps.ssc.nsw.gov.au/ShireMaps/?layerTheme=Planning/Zoning ? Literally half the following suburbs seem to be flood affected: Caringbah, Sylvania, Sylvania Waters, Taren Point, Woolooware. I accept that Sylvania Waters is extremely low lying and may be affected by sea level rises over many years, but I don't know about all those other areas and why they'd be considered flood affected from a stormwater run-off perspective?

We had a massive rain event a couple months back and I don't recall much flooding in the Shire making the news? Is the council just being overly cautious and covering their asses? Makes it extremely difficult to buy anything in those suburbs as every second house is flood affected. And it's not like any of them are designed with flooding in mind.

 

Link doesn't work.
As it is to do with planning, I suspect it is on the cautious side and they want you to build to allow for possible flood, think 1 in 200 year event.

Most of Kurnell is a flood zone, they now make you build up, well above ground level, still you can dig down 2-3 feet and find the hole fills up.

With the wind blowing the right way, a king tide and a heap of rain pretty much anywhere is in trouble these days
(due to the amount of roof/paving catchment there is nowhere for it to soak in, so more than ever is going to aging drainage infrastructure that can't cope).

 

That's a combination of a high water table & sand, not attributed to being in a flood zone.

A fair section of Kurnell does flood in a sustained rain event.

 

This link should probably work

https://maps.ssc.nsw.gov.au/ShireMaps/?layerTheme=Planning/Zoning