[OSM-talk] coastline accuracy?

[Ed Loach]

> Nothing on the tag:natural=coastline page says you can't tag
> anything on the
> sea-side of it. See
> <http://wiki.openstreetmap.org/wiki/Tag:natural=wetland>
> 
> And then the extended usage:
> wetland=tidalflat
> wetland=saltmarsh
> wetland=mangrove

But reading the discussion page, they "flexibly" interpret the
coastline as highwater line recommendation and suggest moving it to
the seaward side of whatever feature that is being tagged and adding
tidal=yes to the bit between the coastline and the high tide line.
Effectively this suggests that the coastline should be moved to the
low tide line, with whatever landuse/natural is between low tide and
high tide mark being tagged with tidal=yes, rather than have the
coastline as the mean high water mark.

Ed