[Imports] Proposed import of South Australian waterbodies data

Henry Haselgrove haselgrove at gmail.com
Sun Feb 8 23:59:49 UTC 2015


	From: Christoph Hormann [mailto:chris_hormann at gmx.de] 
	Sent: Tuesday, 27 January 2015 10:36 AM

	> 'Land - Subject to Inundation' does not corretly translate to natural=wetland - which requires water saturated soil for
	> a significant part of the year.  According to the documentation you linked to the data set also includes other attributes
	> that might help to generate a more precise tagging.

I wasn't able to find any part of the documentation that contradicted the OSM definition of wetland. I agree that the name "land subject to inundation" suggests something a little different to a wetland. However, I have studied the names of the features, and the appearance of many of them on Bing, and I believe that they fit the OSM definition of wetland well. Of the features in this class that have a name, 40% of them are "xxx Swamp", for some value of xxx . Less than 1% of the names are "xxx Flood Plain" or "xxx Floodplain". Features appear to be a combination of swamps, salt marshes; as well as wetland areas on the edges of lakes and rivers. The description of the complete dataset on the source website is "Includes natural features such as lakes and wetlands as well as artificial features such as dams, reservoirs and urban lakes.", which (sort of) implies that the creators of the data consider that class of features to be wetlands (given that dams, lakes, and reservoirs are covered by the other feature codes). The other attributes you mention don't seem to provide any useful information unfortunately.

	> Your selection of 10k features from 150k total is not clear to me.  Why these 10k and do you plan to also import the rest later?

I only have very tentative plans for the rest at the moment. It is an enormous amount of data, and I estimate it would require around 400 changesets. It is something that would need to be planned and carried out over a significant period of time. I want to import what I consider to be the most important part of the data sooner rather than later. However, I realize that "all features having a name, plus all permanent lakes" is a somewhat arbitrary definition of "important". Also, this is my first ever bulk import, so I wanted to start with a modest sized data set, and use the experience gained from that to help me develop plans for future imports.




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