[Tagging] Flood mark or high water mark

Robert Szczepanek robert at szczepanek.pl
Tue Aug 7 19:00:21 UTC 2018


W dniu 06.08.2018 o 01:48, Warin pisze:
> On 06/08/18 09:01, Dave Swarthout wrote:
>> > I would think a good start would be changing the wiki to make it 
>> historic=flood_level, leaving any reference to high (or low) water to 
>> be a waterways thing ie the high tide mark.

Before making any changes in wiki I would like to find final agreement 
on that topic.
"Flood level" (highest water table) is usually only one of several 
informations we can find on "flood mark". Others can be date of flood, 
inscription, etc.
Physical object mapped in OSM is rather mark, not just water/flood level.
So "historic=flood_mark" is probably more generic.

>>
>> +1
>>
>> Very sensible IMO.
> 
> Yes.
> Complication .. a historic king tide combined with a storm event may be 
> considered a historic flood level.
> But 'normal' high tides should be part of the water way tagging system.
> 

This can be sometimes hard to distinguish. But tide+storm I would 
consider rather as flood event - probably higher level comparing to 
periodic tides.
In such a case we can find in on place two types of marks:
* historic=highwater_mark - with information about periodic highest 
water level (no date provided),
* historic=flood_mark - with information about flood event (with date)
So existence of date on such mark could be a good information for proper 
tag assignment. I'm not familiar with tides, so please correct me if 
this is not the case.

regards
Robert

>> On Sun, Aug 5, 2018 at 2:59 PM Graeme Fitzpatrick 
>> <graemefitz1 at gmail.com <mailto:graemefitz1 at gmail.com>> wrote:
>>
>>
>>
>>     On 6 August 2018 at 02:48, Robert Szczepanek <robert at szczepanek.pl
>>     <mailto:robert at szczepanek.pl>> wrote:
>>
>>         W dniu 05.08.2018 o 12:23, Volker Schmidt pisze:
>>
>>             Flood marks and high water marks are not necessarily the
>>             same thing.
>>             Read
>>             https://en.wikipedia.org/wiki/High_water_mark
>>             to get the gist.
>>             There are ordinary high water marks (and I suppose also
>>             the opposite, ordinary low water marks) which are based on
>>             the regular tides in the area.
>>             A flood mark would be a marker for the water level reached
>>             in certain, particular events.
>>             I am not sure about terminology in different
>>             jurisdictions, but the concept seems to be clear to me
>>             that there are two different things we want to tag.
>>
>>
>>         I would like it to be so:
>>         - flood marks as flood signs,
>>         - highwater marks as tide signs.
>>         But even in recent scientific papers this division is not so
>>         clear.
>>
>>         Another issue is that from the beginning, on OSM wiki
>>         https://wiki.openstreetmap.org/wiki/Key:historic
>>         mark related to floods is described as
>>         historic=highwater_mark
>>
>>         What would be the optimal tagging solution from OSM point of view?
>>
>>         regards
>>         Robert
>>
>>
>>     I would think a good start would be changing the wiki to make it
>>     historic=flood_level, leaving any reference to high (or low) water
>>     to be a waterways thing ie the high tide mark.
>>
>>     Thanks
>>
>>     Graeme
>>     _______________________________________________
>>     Tagging mailing list
>>     Tagging at openstreetmap.org <mailto:Tagging at openstreetmap.org>
>>     https://lists.openstreetmap.org/listinfo/tagging
>>
>>
>>
>> -- 
>> Dave Swarthout
>> Homer, Alaska
>> Chiang Mai, Thailand
>> Travel Blog at http://dswarthout.blogspot.com
>>
>>
>> _______________________________________________
>> Tagging mailing list
>> Tagging at openstreetmap.org
>> https://lists.openstreetmap.org/listinfo/tagging
> 
> 
> 
> 
> _______________________________________________
> Tagging mailing list
> Tagging at openstreetmap.org
> https://lists.openstreetmap.org/listinfo/tagging
> 



More information about the Tagging mailing list