Mekelle Mapping Guide

Mekelle, Ethiopia

Mekelle is the capital city of the northern Tigray region of Ethiopia. It is the third largest city in the country after Addis Ababa and Dire Dawa, with an estimated population of 215,000. Geospatial data of the city's infrastructure is needed to assess and then provide basic water and sanitation services. Help us map Mekelle using current high-resolution imagery. We will digitize roads, buildings and other major features within the city. OpenStreetMap will be used as the platform to digitize and store data for usage by students, planners and geospatial enthusiasts. Mekelle is a city of interest for the Department of State's Secondary Cities Initiative. Secondary Cities is the United States Office of the Geographer’s flagship field-based initiative to assist rapidly growing cities to build capacity for data generation for resiliency, human security, and emergency preparedness.

Go to project 1710 on the HOT Tasking Manager

Classifying Roads

highway = *

All roads are classified as some type of highway. Roads are primarily classified based on their function. Tertiary roads connect villages and major streets in towns of some importance. Secondary and Primary roads connect medium and large cities. Motarways are restricted access highways. Sometimes it is difficult to immediately recognize what type of roads exist. An option is being able to re-classify some of the roads at a later point.

In this project, most of the roads you collect will be either a tertiary road, residential road, track, or path.

surface = *

In addition to using the highway tag, one can 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.

Residential Roads

highway = residential:

This tag is used for roads in or around residential areas except the major roads. Generally we would want you to classify a road this way if you suspect that it is used mostly by people that live on the road. Roads lined by residential buildings are good signs. If your unsure than use 'unclassified' value.

Paths

highway = path:

highway=path is a generic path, either multi-use or unspecified usage, open to all **non-motorized** vehicles . The path may have any type of surface.</h4>

This includes walking and hiking trails, bike trails and paths, horse and stock trails, mountain bike trails as well as combinations of the above.

Buildings

Tracing buildings takes good imagery and patience. Take your time and pay attention to angularity, alignment between buildings and reflecting the regularities between buildings.

Select new Area (Keyboard Shortcut: 3) in iD and put a node down at every corner of the buildings roof. Double clicking will complete the area. If you havent formed perfect right angles at every building corner don’t cry, you can ‘shift-click’ on the area to bring up the contextual area menu and use the tool to orthogonolize the area (Keyboard Shortcut: s).

Buildings should be traced as outlines of where the building meets the ground. This last piece is important. The roof outline is often easier to see in the imagery so you’ll find it often traced in OpenStreetMap but it’s wrong. If you see that the outline of the roof you traced does not align with where the building meets the ground you can ‘shift-click’ the path and use the tool to drag the path to the correct position.