UN Maps Project/UN maps for Somalia

From OpenStreetMap Wiki
Jump to: navigation, search

The first mission involved in the Dynamic TLM Project is UNSOS (Somalia). This project will provide complete, accurate and always updated Somalian data related to topographic features.

The most relevant features we need are:

  • roads
  • waterways
  • residential areas


Instructions

In general, refer to the OpenStreetMap map Features: https://wiki.openstreetmap.org/wiki/Map_Features


Tasks currently active

#5701 - UN Maps: Roads around Wanlaweyn, Somalia


Roads

Particular attention must be applied to the extraction of Highway.

Please pay close attention to roads geometrical accuracy and on the correct tags. Attention must be applied to the surface and hierarchy attributes.

Map roads, tracks and paths as completely as possible by connecting them to the main road networks wherever possible and only if clearly visible. The Wiki page “Highway Tag Africa” could be useful during the Highways mapping (https://wiki.openstreetmap.org/wiki/Highway_Tag_Africa).

Roads classification


Tag (key, value) Kind of road Description Note Satellite image
highway=primary Primary Road Major transportation routes between and into major cities within a country. Engineered alignment. Width: 5 to 20 meter; often paved
Imgsat Primary Road.jpg
highway=secondary Secondary Road Major transportation routes connecting cities and large towns. Collector function in urban areas. Width: 3 to 7 meters; may be paved or compacted
Imgsat Secondary Road.jpg
highway=tertiary Tertiary Road Major transportation routes connecting towns and larger villages. Collector function in urban areas. Width: 3 to 7 meters; may be paved or compacted
Imgsat Tertiary Road.jpg
highway=unclassified Minor/Unclassified Road Minor collector roads that allow travel and commerce from paths and residential roads to and between settlements. While generally not residential, there can be houses along the road. Width: 3 to 7 meters; may be compacted
Imgsat Unclassified Road.jpg
highway=residential Residential Road In urban areas or rural villages, roads which serve as an access to housing, without function of connecting settlements. Often lined with housing. This tag is used only in urban areas and only on roads which serve no other purpose than residential. 3 to 7 meters; may be compacted
Imgsat Residential Road.jpg
highway=service Service Road Mainly Private Driveways or access roads to homes or businesses for a few hundred meters maximum, does not have a through connecting function. Width: 3 to 7 meters. May be paved or compacted
Imgsat Service Road.jpg
highway=track Unmaintained Track Road Access route from dwellings to agricultural and forestry areas. Roads within National Parks and Game Reserves may be tagged as tracks. No connection function between settlements. Width: 3 to 7 meters. Not paved, not compacted
Imgsat Track.jpg
highway=path Path Travel route between dwellings, settlements, or water sources, and for livestock movement. May be the primary access route for isolated settlements. Connection way by foot within an urban area. Steep grades, narrow width, irregular alignment, obstacles, boulders, stream crossings, and seasonal use. Width: 1 to 3 meters. Not paved, not compacted.

While you are free to map paths, you are not requested to map this feature for UN Maps Projects.

Imgsat Path.jpg


Road surface

Always indicate the physical surface of the road with the surface tag.

Generically, a hard surface (asphalt, cobblestone, concrete...) is indicated with surface=paved and a soft one (ground, sand...) with surface=unpaved.

The default tag for the roads must be unpaved: surface=unpaved.

Example of unpaved road in Bur Hakaba, from satellite images



Only for the principal/major unpaved roads the tag will be surface=compacted. This kind of unpaved compacted roads could be defined as “all weather road”. Those are constantly maintained roads and characterized by a very regular development. This kind of surface is composed of a mixture of larger (e.g., gravel) and smaller (e.g., sand) parts, compacted (e.g., with a roller), so the surface is more stable than loose gravel.

Example of unpaved compacted road in Bur Hakaba, from satellite images


Description can be more precise:

  • surface=unpaved

or, if further details are available

  • surface=compacted
  • surface=fine gravel
  • surface=gravel
  • surface=pebblestone
  • surface=dirt
  • surface=earth
  • surface=grass
  • surface=grass_paver
  • surface=gravel_turf
  • surface=ground
  • surface=mud
  • surface=sand
  • surface=woodchips

Please, for any detail see the Key:surface wiki page.



Only for paved roads the tag must be surface=paved.



Example of paved road in Bur Hakaba, from satellite images



Description can be more precise:

  • surface=paved

or, if further details are available

  • surface=asphalt
  • surface=concrete
  • surface=concrete:lanes
  • surface=concrete:plates
  • surface=paving_stones
  • surface=metal (Used for bridges, or for temporary tracks over fields for normal road vehicles or site traffic)
  • surface=wood (Used for bridges, plank walkways, and garden decking)

Combination of Hierarchy and Surface tags

  • primary/secondary/tertiary highway=* are supposed to be paved or compacted
  • residential highway=* could be compacted
  • highway=track and highway=path are supposed to be unpaved by default

Waterway

Please pay close attention to waterways geometrical accuracy and on the correct appearance tags.

To map a waterway draw a line. The direction of the line should be downstream - in the direction that the river flows. The most important thing is to maintain consistency in the water network. Every waterway should connect to another one.

Use Water Features:

waterway=river for large waterways (>10m) waterway=stream for small waterways (<10m)

perennial river, from satellite images


perennial stream, from satellite images


Appearance tags: By default a waterways is considered as perennial, but many rivers and streams could be either intermittent or seasonal.

seasonal=yes intermittent=yes

intermittent or (maybe) seasonal river, from satellite images


intermittent or (maybe) seasonal river, from satellite images


For small waterways, a line along its path is sufficient, but when a waterway becomes wide enough, mapping the area it flows through as water=riverbank is desired in addition.

a river with its riverbank drawed within JOSM


Landuse

Close attention must be applied to attributes and extraction accuracy for Residential areas.

All the big town (as for example Baidoa) must have at least the following tags:

landuse=residential

Landuse and additional tags should be applied to the area, drawing a closed way around the huts and buildings.

Example:

landuse=residential name=Baidoa place=town

Baidoa town, from satellite images



Small residential areas must have only the following tag (add the tag name if available):


landuse=residential


Other residential area outside the Baidoa town, from satellite images



Villages, composed of a lot buildings and huts, must have at least the following tags (add the tag name if available):


landuse=residential

place=village


Example of village in the Baidoa district, from satellite images



Small villages, composed of some buildings and huts, must have at least the following tags (add the tag name if available):


landuse=residential

place=hamlet

Example of hamlet in the Baidoa district, from satellite images



Isolated dwellings are the smallest kind of human settlement. They are outside other settlements. Instead of bigger settlements, the isolated dwellings are mapped just with a node. They must have at least the following tags (add the tag name if available):


landuse=residential

place=isolated_dwelling

Example of isolated dwelling in the Baidoa district, from satellite images


Fence

In some African areas, fences are an important part of landscape. They are visible from satellite images.

Natural fence in Somalia, from satellite images



Draw a line on the fence and apply the tag barrier=hedge (or barrier=wall if is made of concrete or other not natural material).