Good evening, I'd be really appreciative if anyone was able to provide a website to source reliable flood zone maps for Brisbane. I'm not very familiar with brisbane, but understand quite a few suburbs have streets which are particularly flood prone and can influence things like asset type and insurance costs. Kind regards
Can i just encourage disclaimers here? You asked for reliable and they are not reliable. They are a bit of a mash of height information, historical information (which doesn't predict the future) hydro analysis, and assumptions. I for one don't believe they are updated frequently, and although height changes only marginally, my personal view is the risk from river flooding vs flash flooding is changing and this is not acknowledged. You can be quite high up and subject to overland flow, flash flooding, and you can be quite close to a river with less of a risk. Locals can give information (also unreliable ) and historic events can give indications (unreliably of course). So if i was you i would seek a qld insurer who insures against flood as a precaution if you really don't want to be 'burnt' by flood. Opinion (unreliable opinion) only
Very true. My BIL house is halfway up a hill, nowhere near a waterway. But during one heavy storm, house was inundated by water from the top of the hill. The Y-man
I think the council recently updated flood map, but still... Brisbane's flood map updated, changing the flood levels of tens of thousands of properties
The subtext here is how resistant ppl are to updates as no one wants to be be 'in' rather than 'out, but flooding is not a binary thing. It is about levels. Who cares if a mm goes in the corner of a block? Why does that attract blue, when total inundation also attracts blue, and bad flooding is left out altogether? What council scores an own goal by allowing flood area development which shows up in its own blue mapping? Be VERY cautious. More flooding expected, but fewer properties affected ......really? Maybe the assumptions are historical .... don't add the 1.5 degree by 2030 expected?
Be a little more old school.....drive the road and see where elevated houses stop . Even google drive it
I very recently bought a property that has council flood mapping show the block edge in council flood mapping (but it's damn near a dead flat block !). I walked the street, spoke with two different residents who lived in the street 50 years, never been a flood Yep, if it's a sloping block Best way to go All very good points raised, and almost anywhere can flood these days Yep, with development getting more high density there's more roof catchment area, then we concrete everything else so there's no area's for ground absorption so all that water is caught and gets directed into 60yo council drainage infrastructure that was never designed or built to take the volume
I think the flood maps are a good starting point. But yes, consider local layout, recent developments and if you can drive there. I like looking at the contours on the council's maps. That layer plus flood risk layer gives you a good idea of what will happen under more extreme events. Which areas are next in line to flood or have run-off/ overland flow. But there is nothing compared to checking out a place in person. Recent developments can make maps obsolete.
This blog article will provide the links that are currently available to assess flood risk and it will also explain how to interpret the information. I hope this helps! How to Assess Flood Impacts in Brisbane
Be aware that every flood is different. There were significant differences between inundations in 2011 compared to 1974. Some areas were more affected in one compared to the other.
They are different. @Marg4000 is on the money. My thoughts ( opinion only ) is that inundation through flash flooding is on the increase. That is heavily influenced by the event itself ( intense rain ) and the capacity of the storm water network. Just recently Toowoomba had an event ( hail as well ) where stormwater pipe blockages were a factor. No river involved. Just opinion.
