Tag:barrier=berm

barrier=berm
Description
A berm is a level space, shelf, or raised barrier (usually made of compacted soil) separating two areas  
Rendering in OSM Carto
Group: Barriers
Used on these elements
See also
Status: in use

Proposal

NOTE: The definition on this page is a proposal, not a description of current use of this tag.


A  Berm is a level space, shelf, or raised barrier (usually made of compacted soil) separating two areas. It can serve as a fortification line, a border/separation barrier, in industrial settings, or in many other applications.

This feature is more commonly mapped with man_made=dyke or man_made=embankment

Description

There are several uses for berms, including as:

Military Use:

In medieval military engineering, a berm (or berme) was a level space between a parapet or defensive wall and an adjacent steep-walled ditch or moat.

During World War I trench warfare, the name was applied to a similar feature at the lip of a trench, which served mainly as an elbow-rest for riflemen.

In modern military engineering, a berm is an earthen, or sod, wall or parapet. Walls constructed in this manner are an effective obstacle to vehicles, including most armoured fighting vehicles, but are easily crossed by infantry. Because of the ease of construction, such walls can be made hundreds or thousands of kilometres long.

A prominent example of such a berm is the 2,700 km (1,700 mi)  Moroccan_Western_Sahara_Wall.

Berms are also commonly used to surround explosives, or ammunition, storage depots, so as to direct the force of any explosion harmlessly upwards, rather then outwards at ground-level.

Another similar use for them is to surround parked aircraft, both to provide protection to ground personnel in case of the aircraft exploding, & also to protect the aircraft from the explosion of nearby bombs.

Erosion control:

Berms are also used to control erosion and sedimentation by reducing the rate of surface runoff. The berms either reduce the velocity of the water, or direct water to areas that are not susceptible to erosion.

Noise Control:

in modern highway construction, a berm is a noise barrier constructed of earth, often landscaped, running along a highway to protect adjacent land users from noise pollution.

Pollution control:

Berms are also used as a method of environmental spill containment and liquid spill control. Bunding is the construction of a secondary impermeable barrier around and beneath storage or processing plant, sufficient to contain the plant's volume after a spill. This is often achieved on large sites by surrounding the plant with a berm.

Shooting Ranges:

Berms are also used as protection around open-air shooting ranges, to prevent fired projectiles from leaving the range boundary. They can be used either as a backstop, behind the targets, or to separate groups of shooters.

How to map

Depending on the width of the berm, it can be mapped either as a simple line, drawn along the centreline of the wall; or as an area enclosing the outer boundaries of the wall.

Tags used in combination


height=*, the height of the wall
material=*, what the wall is made of


Similar tags


External discussion

This article is issued from Openstreetmap. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.