|An area in the tidal range.|
|Used on these elements|
|Status: de facto|
|Tools for this tag|
The tag tidal=yes indicates that an element is in the tidal range. It could be a river, a shore, a part of a harbour or a water area.
When the part of the harbour has a gate which does not let the tide in you may tag it with tidal=no. But this is the default value so it is not really necessary.
How to map?
waterway=river + name=* + tidal=yes
natural=water + water=river + tidal=yes
If you know where are the limits of the tide and of the river (because you have imagery at low tide and another at high tide), you can add 3 areas (closed ways or multipolygons), one for the river's water body and 2 (one on each side of the river) with tags natural=wetland + wetland=tidalflat (if these are muddy areas : you don't need in this case of tidal=yes) or natural=sand + tidal=yes (if areas are sandy) or natural=shingle + tidal=yes or any other tags (according to the type of soil) + tidal=yes.
Tidal area at sea
Areas in the tidal range between mean high water springs (natural=coastline) and mean low water springs can be tagged with tidal=yes to explicitly indicate this.
natural=bare_rock + tidal=yes
natural=sand + tidal=yes Don't use natural=beach for an area under water at high tide, the value beach is only for the part above the coast line (see natural=sand)
If the foreshore is a mudflat, you may use the tags natural=wetland + wetland=tidalflat. These tags already imply that the area is in the tidal range so you don't need of tidal=yes.
|yes||Indicates that an area is in the tidal range. The top of the tidal range is generally taken to be at natural=coastline i.e. the mean high-water springs (MHWS).|
|no||Default. Disambiguates whether item is not in the tidal range or has not been considered for tagging. Not explicitly required.|
You can also add the type of this area: