[Tagging] Seasonal, intermittent, and ephemeral water tags

[Andrew Davidson]

On 26/05/18 23:27, Tod Fitch wrote:
 >
> Those definitions match up with my understanding. So something like
> 
> waterway=* (or natural=spring | water )
> presence=perennial | seasonal | intermittent | ephemeral
> 
> If the presence is seasonal, then the existing seasonal=* could be used 
> to describe what times of year the item is normally present.
> 

As well as presence other options for a new tag would be:

*persistence eg:

http://inspire.ec.europa.eu/codelist/HydrologicalPersistenceValue

*permanence eg:

https://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=159984

Permanence seems to be the more commonly used term.

I wouldn't include the seasonal value as there is already a seasonal key 
and we should use that.

In effect what I think we need is to generalise the existing stream key:

https://wiki.openstreetmap.org/wiki/Key%3Astream

so it can be used on other water objects (assuming that people would 
think that natural=wetland + stream=ephemeral would look odd--otherwise 
no need for a new key).