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<div class="moz-cite-prefix">On 25-Sep-16 08:48 PM, Colin Smale
wrote:<br>
</div>
<blockquote
cite="mid:2668372A-0AEB-4696-8536-DDA4710797C3@xs4all.nl"
type="cite">Where would the boundary be? How could we describe it
objectively? In low lying areas such as the Netherlands there are
sometimes so called winter dykes which give a sharp edge to the
flood plain. Otherwise it would all be a bit vague around the
edges.<br>
//colin<br>
</blockquote>
<br>
Problems of defining a boundary exist with river banks too. <br>
<br>
Here is a document on part of a flood plain .. only about 60 kms
long. <br>
<a class="moz-txt-link-freetext" href="http://www.environment.nsw.gov.au/resources/floodplains/120163JemalongCondobolinFMP.pdf">http://www.environment.nsw.gov.au/resources/floodplains/120163JemalongCondobolinFMP.pdf</a><br>
Note that the document is copyright ... Yes boundaries are a 'bit
vague', they are a 'bit vague' for scrub, wood, sand etc too. <br>
<br>
<blockquote
cite="mid:2668372A-0AEB-4696-8536-DDA4710797C3@xs4all.nl"
type="cite"><br>
<div class="gmail_quote">On 25 September 2016 12:30:50 CEST, Warin
<a class="moz-txt-link-rfc2396E" href="mailto:61sundowner@gmail.com"><61sundowner@gmail.com></a> wrote:
<blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt
0.8ex; border-left: 1px solid rgb(204, 204, 204);
padding-left: 1ex;">
<pre class="k9mail">Hi,
There is a draft to tag floodplains using the key natural.
<a moz-do-not-send="true" href="http://wiki.openstreetmap.org/wiki/Proposed_features/floodplain">http://wiki.openstreetmap.org/wiki/Proposed_features/floodplain</a>
My thinking is that this would lead to conflicts with other 'natural'
tags .. like natural=scrub than may be applied to the same area.
So .. what would be the best key to use for this feature/value?
I am thinking that as it is associated with a waterway (it must start to
flood from somewhere and that is usually a waterway) that the key
waterway should be used. It would have rendering similar to a lake - but
'intermittent' so dashed lines rather than a solid colour.
Thoughts?
{There is presently flooding in some areas of Australia, why my thoughts
have turned to this. All too soon it will turn to bushfires}
</pre>
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<br>
<br>
Sub tags could be used to tag frequency etc. These tags could also
be used on floodways that are already part of OSM mapping.. so
should be something like flood:frequency=10 years. <br>
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