Today Brisbane City Council has released information on "Overland Flow" - overground flooding of properties in the "1 in 50 years flood event".
BCC say their data is not accurate but it is essentially flagging properties so that DA will not be approved without a hydraulic engineer report, and that minimum floor heights will have to be 30 - 50 cm above the 1 in 50 year flood height, attention will be paid to runoff into neighbours yards etc.
Despite what the council say:
Originally Posted by BCC
Will the value of my property be affected?
The risks of flooding from river, creek, storm tide and overland flow are not new. All the mapping does is recognise the existing risks and plot them on a map.
Information from property media "Flood maps won't affect house prices, experts say"1 and from the Real Estate Institute of Queensland2 do not indicate that property values will be affected.
Remember that the presence of an overland flow path on a property does not mean it will flood regularly or often. It is merely an indication of the path water runoff may take during a rare one in 50 year rain event.
I'd say the value of my property has been affected and I'd be avoiding the purchase of any properties on this unless you are able to get a clean bill of health from and RPEQ qualified engineer or are happy not to do any development. A BCC flood report done last month on my property says there is no flooding, now it says that flooding is possible due to overland flow.
Hopefully this information helps someone.
PS: I don't work for BCC - but one of my IPs is on the list