Key:embankment

Description

A dyke or raised bank to carry a road, railway, or canal across a low-lying or wet area.

Group: properties

Used on these elements

How to map

Draw a way and add the appropriate highway=*, railway=* or waterway=* tag as a top-level tag for the element. Add the embankment tag with either one of the documented values from the table below or another value as can be found on taginfo

When mapping embankments as separate elements, you can also draw two parallel ways and add man_made=embankment to both. See below.

Unlike bridges, a layer tag is rarely needed for embankments and should not be used without a good reason.

Actual usage

Main usage: whether or not a way is raised on an embankment

The two values for =* that are used most often describe whether or not a way is raised onto an embankment: =yes and =no together make up more than 96% of all usage as per Taginfo 2023-01

Tag	Value	Description
	`yes`	The way is raised onto an embankment
	no	The way is not raised onto an embankment

Other usage: the side(s) the downward slopes are located

Some 2% of usage of =* describes on which side of the OSM-way the downward slope(s) are located, with undocumented values such as =left ; =right ;=both or =two_sided

Other usage: the subtype of embankment

Some 2% of usage of =* describes the subtype of the embankment, such as :

	`dyke`	An embankment for flood protection (called a dyke or levee) which also carries a road or railway. Also see `man_made=dyke` when there is no highway or railway constructed on top

or undocumented values such as =levee or =noise_barrier

Since using =* for describing the subtype of the embankment prevents using =* for the location of the downward slope -and vice versa- such specific details are best described in a specific sub-key such as embankment:type=* and embankment:side=*

Rendering

Single line embankments

Embankments that share a way with a highway, railway or waterway should be rendered with "spikes" on both sides.

This is supported in Osmarender (which is no longer maintained) and alt-Carto style from Tracestrack.

https://tracesmap.com/#17/51.7941/4.8244

Embankments as separate elements

Embankments as separate elements in OSM should be rendered with the left-hand side of the way being the high side and the right-hand side being the low side. (Supported by OSM Carto, but only for non-closed ways that are tagged with man_made=embankment, not for those tagged with =yes.)

To represent a raised finger of land (as in the illustration): draw two ways bordering the raised land, each tagged man_made=embankment and going in opposite directions.
To present a banked enclosure (such as an iron-age hill fort): draw two ways with the outer way travelling anticlockwise and the inner way clockwise. Additional ways can be used to present ditches, scarps, aprons and terraces in large sites. Note that if a closed way is drawn without two breaks (creating two separate but connected ways) then it will be interpreted as an area and not displayed in the Standard layer.