OSM Tasking Manager/Default roads, buildings, waterways instructions

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The following basic instructions have been tuned specially for the most common needs in humanitarian projects for HOT. They are intended to be concise and usable for rapid start by beginners.

Residential areas

This is generally requested in a first step for areas where lot of mapping is missing in order to locate where people live. For such projects, you don't need to trace all roads, but only basic roads interconnecting them or passing through them to build a basic network.

  • Please draw one large area outline around groups of buildings and tag them as a landuse=residential area.
  • About 5 or more buildings can be outlined as a landuse=residential area.
  • Do your best to keep the outline close to buildings and not include a lot of farmland or forest.
  • When to draw the residential area outline takes some judgement, but when in doubt, draw an outline around the settlement.

Project specific mapping notes

  • Many of these squares will already be partially or fully mapped, map in more if needed or fix up the existing mapping, or just mark it "Done" if it is already complete.
  • Please connect up roads that are not connected to the main network or nearby roads.
  • Please disconnect roads that are attached to landuse=residential areas and draw them into the settlements and connect them to other roads that enter the settlements.
  • Existing mapping does not match imagery – This happens in some areas. Use the Bing imagery, but adjust it so it aligns with the existing mapping, then continue mapping. Please leave a comment in the Tasking Manager when you mark done/stop mapping to say you adjusted the imagery. Animated GIF how to adjust background imagery in iD (by Blake Girardot, on Google Photos).
  • Waterways are challenging in this area, more need to be mapped, but please only map the streams and rivers.
  • Many of the buildings are round huts. In the iD editor draw a 3 pointed triangle the size of the hut, then select it, hit the O key and it will turn round. Tag it a building and then you can copy/paste it to other huts of the same size quickly.
  • A 5 minute video that uses iD to edit most of the above points for this mapping project, an example in South Sudan (by Blake Girardot on Youtube).

Roads and paths

  • Please map roads and major paths as completely as possible by connecting them to the main road networks where ever possible.
  • Very short segments that do not connect to anything should not be mapped.
  • Short segments of a road or path that you cannot see through the trees but seem very likely to exist should be mapped to keep the road complete.
  • Try and map a little beyond your task square so the person who maps the task square next to yours can easily connect them.
  • Always connect roads to other roads where they meet and never end roads on Residential area polygon edges.

You will most often use the following road classifications (JOSM):

  • highway=unclassified – This is for roads that a vehicle with 4 wheels could travel on that connect small villages and settlements.
  • highway=residential – These are roads that are in settlements that only are used for access to houses and buildings.
  • highway=track – This is for roads that a 4 wheel vehicle or farm tractor could travel on and only lead to farm fields or forests. They do not connect settlements.
  • highway=path – This is for small paths that a 4 wheeled vehicle could not travel on and are usually used by people on foot or 2 wheeled vehicles. They may or may not connect settlements or lead to farm fields. Only map the major paths that connect to settlements or other roads.

You will most often use the following "Road Features" and "Path Features" (iD Web Editor):

  • Minor/Unclassified – This is for roads that connect small villages and settlements
  • Residential road – These are roads that are in settlements but only are used for access to houses and buildings.
  • Unmaintained track road – This is for roads that only lead to farm fields or forests. They do not connect settlements or residential areas.
  • Path – This is for small paths that are usually used by people on foot or 2 wheeled vehicles. They may or may not connect settlements or lead to farm fields. Only map the major paths that connect to settlements or other roads.

Special project information for experienced or local mappers only

NOTE: Video Demo video of this project - please watch me (6 minute, on Youtube)

  • Very experienced OSM JOSM mappers and local road mappers only please.
  • Much of this is already well mapped, this project is focused on making improvements to the road system only.
  • JOSM only:
    • You must run JOSM validation on the entire task. Fix the easy validation errors, only the ones you are confident fixing. Focus on the road errors and warnings.
    • Upload often and use "Update Data - Ctrl+U" in JOSM often to reduce conflicts.
  • New mappers may be mapping "Buildings only" in the same area of this project. Mapping "under" your road fixes, just be aware of that.
  • Try to pick squares with no one working next to you to reduce conflicts
  • These are very large task squares, again to reduce conflicts. But if they are too large for the API to download only, feel free to use the "Split" link after you have checked out a task square for mapping. It will quarter the task square. That link is there for you to use :) They are intended to download a lot of OSM data to check by running JOSM Validation on, do not make them too small.
  • This is a "one pass" project, it will not need the "Validation pass" This is validation, it does not then need validation. 100% mapped is 100% done. No one will check your work if you mark it done.
  • Never touch a man_made=survey_point node. ;-) If one is attached to a road and you need to move that road, first duplicate it, move the node attached to the road where desired, remove the man_made=survey_point tag from this node, keep the other survey_point node alone.

Validation and improving roads

  • This is intended to be a "Roads only" project. Please run JOSM validate on the entire task square first and identify easy fixes. Low hanging fruit.
  • Fix the road errors and warnings you are comfortable fixing and will not take up too much of your time.
  • If you can't fix something, fix what you can related to roads and duplicate buildings. If you are stopping without fixing "errors", leave a comment on the task and just use "Stop mapping".
  • You can leave any warnings not related roads, we are focused on the roads. And obviously leave alone the road warnings you do not know how or can not fix.
  • Do not edit relations warnings like "Role verification problem" unless you happen to be a relations expert as well and then only if it is something you want to deal with.

Questions (and you should have questions as you will be seeing new warnings) should be directed to the local community main communication channels or HOT slack, general or disaster channel.


  • Please accurately outline all the buildings you can find. The outline should be for the full size of the building even if it is partly covered by trees in the imagery.
  • After drawing the outline, **use the 'S' key in the iD web editor to "square" the corners please**.
  • Many buildings are very close, but do not actually touch each other, try to map them close to each other without letting them connect or share nodes with each other, roads or residential area outlines. In the iD web editor, holding down the 'alt' key will keep nodes of "snapping" to each other and accidentally connecting.
  • In the iD web editor, the first time you map a building you will use the "Building Features" category and then at the top of the list select "Building" again, this is the most generic building tag we can use as we almost never can tell the more specific use of any building from imagery alone.
  • Never touch a man_made=survey_point node. ;-) If one is attached to a building and you need to move that building, first duplicate it, move the node attached to the building where desired, remove the man_made=survey_point tag from this node, keep the other survey_point node alone.
    • Only if you have personal knowledge of a building**, please add that information to the building, like the name or type of building (hospital, school, gas station, etc).

Open areas

  • leisure=common – Open flat areas of grass or dirt in a settlement, often with paths across them.
  • leisure=pitch – An identifiable sports field of some sort, usually football/soccer, baseball (specify sport=* if it is identifiable).
  • leisure=park – An open area that you personally know to be an official park or recreation area
  • landuse=grass – Open, flat grassy area, not a farm field or crops.

Waterways, bridges, fords, dams

  • waterway=stream
  • waterway=river – If you see obvious waterways, please map them. They are usually much lighter color, grey than roads/paths and you can often see rocks and split channels. Much like the road system, please find where the waterway connects to the main waterway network and map it to connection. Mapping waterways implies a direction as well so zoom out, look for already mapped waterways nearby, or use the OpenCycleMap background layer to help determine which direction the water flows.
  • bridge=yes – This tag is placed on a segment of road that is just the same size as the bridge and also needs a tag that says layer=1 to indicate it is above the waterway. The waterway and the road do NOT share a node.
  • ford=yes – If you see a road crossing a waterway try to confirm a bridge or a ford. Fords are places where the road just drives through the waterway. To map a ford, have the waterway and the road DO share a node and put the ford=yes tag on that one single node.
  • waterway=dam – Dams are a little confusing to map, please see the references listed below and ask a more experienced mapper to help you. But they are important to map if you can identify them.

General mapping notes

  • Be as precise as possible – This takes a little bit of practice, but following a road closely or the outline of a building carefully really makes a difference in the quality of map data produced. Quality is more important than quantity when it comes to mapping. Zooming in close helps.
  • changeset comments – These are filled in with some default information but you should always add what you mapped. For example "added buildings and roads" or "added in some waterways".
  • It is ok to "split" task squares – Sometimes a task square will have a lot detailed settlement mapping. If you think it would help to make the task square smaller so the mapping could be finished in a more reasonable time, use the "split" link above the task square comment box.
  • Personal knowledge – If you have local knowledge, that is incredibly valuable and any information you are 100% sure of you can add to the object you are mapping. Building names, health facilities, names of roads, etc, are all very valuable and the name=* tag can be used to supply that information.
  • Sometimes a task square is already mapped – Sometimes you will find a task square that looks totally mapped or has nothing in it to map. Just double check that it is complete, map anything that was missed, straighten up anything that needs it and then mark it "Done".
  • Invalidated task squares – You might get a notice that a task square was "invalidated" that almost always just means someone found a few more things to map and they did not have time to map them in. No worries, it is part of the process and happens all the time. If you have to stop mapping before you have mapped everything use the "Unlock" link instead of "Done". As long as you are trying to map everything in a task square you feel confident mapping before you mark one "Done" then all is good.
  • Ask questions – if you have questions, please ask. The front page of this HOT Tasking Manager website offers a few ways to ask or if you are at a mapping event, raise your hand and ask.
  • You are making a real difference mapping – Every contribution matters in a real, tangible way. Mapping in not easy but know that your mapping is used by humanitarian organizations around the world every single day.


This OSM wiki is where you can find detailed information on how to tag objects, below are some of the most relevant pages to typical humanitarian mapping projects.

  • Highway Tag Africa – An excellent guide to typical humanitarian road mapping.
  • highway=* : highways, roads, streets, tracks, paths, footways – More than you want to know.
  • Waterways – How to map natural waterways or canals.
  • building=* – How to map buildings.
  • waterway=dam – How to map a dam.