[talk-au] Brisbane Flooding on NearMap

[Andrew Harvey]

On Sat, Jan 15, 2011 at 1:37 PM, Brendan Morley <morb.gis at beagle.com.au> wrote:
> Folks
>
> NearMap's flood run of Brisbane is partially online.  e.g. in the CBD
> through to Oxley Creek at least.
>
> Sam Vekemans has expressed interest to me in helping trace the flood line.
>
> All I can say to that right now is please trace not just to the level of the
> visible floodwater but also the traces of where it's been.  For example,
> it's fairly obvious on most of the roads where the "high tide" of the
> silt/sludge has been.  This will be an invaluable resource in, essentially,
> "where not to build".
>
> I have no idea what to tag it, I'm sure you'll work something out.

There seems to be two different things here. Mapping out the extent of
the flood and mapping flood prone areas.

For mapping the extent of the flood, if it was going into the OSM
database I would suggest it be tagged as a historical item, ie.
something like natural=water, historical={{timestamp}}.
It might be worthwhile looking into the josm lake walker plug in to
see if it can help automate the classification of the flooded region.

For mapping a flood prone area, I suppose it depends a lot on the size
of the flood, ie. the higher the flood the larger the area. If just
one area is mapped, where the line is placed will be subjective.
Perhaps it would be better to put data into the database that would
allow for flood modeling, so that you can determine for any give flood
height, the resulting flood prone area. This is just a thought though.