The Ethiopian Mapping Authority (EMA) is the official organization responsible for mapping, surveying and remote sensing activities in Ethiopia. The organization was established in 1954 under the reign of Emperor Haile Selassie I as a department in the Imperial Ethiopian Ministry of Education.
Currently, EMA’s key responsibilities and duties include collection, compilation, analysis, production/publication, administration, and distribution of the following sets of fundamental geospatial information data sets in Ethiopia: geodetic control networks (ground control points); remotely sensed imagery (aerial photographs, satellite imagery); topographic (base) maps; thematic maps including transportation, utilities and services, the natural environment and tourist maps; hypsography which includes contours, digital elevation model and spot heights ; hydrography involving lakes, rivers and streams; administrative boundaries (international, regional, zonal, woreda, etc.); geographic names; and national Atlas.
Although EMA has made significant contributions to the success of large river valley projects, including hydroelectric power generation and irrigation schemes by sharing reliable mapping and surveying data, limited resources and lack of trained professionals have hampered it from introducing state-of-the-art technologies and meeting current needs of its service users.
In 2007, USAID/Ethiopia and the United States Geodetic Survey assisted EMA to establish Continuously Reference Stations (CORS) network which provides the infrastructure that supports correction factors for GIS-based applications. The CORS were set up in four strategic locations in Ethiopia to provide Global Positioning System (GPS) users with a modern 3-dimensional geocentric spatial reference system. The Institute of Geophysics, Space Sciences and Astronomy of the Addis Ababa University also invested in CORS technology to monitor seismologic activity. The CORS network was set up along with an Online Positioning User Service (OPUS) which is an automated web-based utility that provides correction factors for submitted GPS observation data using the CORS network information.