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Public-images-osm logo.svg tidal
Onehunga Shoreline For Reclamation.jpg
An area in the tidal range. Show/edit corresponding data item.
Group: marine
Used on these elements
should not be used on nodesmay be used on waysmay be used on areas (and multipolygon relations)should not be used on relations (except multipolygon relations)
Useful combination
See also
Status: de facto

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?


way River flow
+ name=*
+ tidal=yes
area River's water body
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.

area Foreshore rocks body
+ tidal=yes
area Foreshore sandy body (for example the part of a beach under water at high tide)
+ 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.


Value Description
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:

Similar objects with deprecated values

If you know places with this tag, verify if it could be tagged with another tag.
Automated edits are strongly discouraged unless you really know what you are doing!

See also