Formerly part of French Equatorial Africa, Chad became fully independent in 1960. Topographic mapping of the country had been started by the French Institut Géographique National (IGN) in the early 1950s and continued in co-operation with the Directeur du Cadastre et de la Topographie, N’Djamena. In 1990, a new cartographic service was established as the Service de la Cartographie, Direction du Cadastre (SCDC).
Almost complete cover of the country at 1:200,000 scale was issued by IGN over the period 1957-77. Most of the south of the country is covered by sheets in the four-colour, regular edition, while many of those in the north are in the Fond topographique or planimétrique format. Projection is UTM, Clarke 1880 ellipsoid and sheets are graticule-based, each covering one degree.
Some four-colour 1:50,000 scale mapping on 15-minute quadrangles was produced by IGN near the southern border in 1950s, and a few more sheets were completed in the late 1960s.
The Lake Chad Basin Commission (LCBC/CBLT) 1:50,000 series produced by the British Directorate of Overseas Surveys in the late 1970s covers Lake Chad and adjacent areas. The 59 sheets in this photomap series are not restricted to Chad, but also cover parts of Niger, Nigeria and Cameroon. The projection of these maps is Transverse Mercator, Clarke 1880 ellipsoid.
SCDC’s main mapping activity has been the production of a number of town and city plans, including a two-sheet plan of N’Djamena at 1:10,000 scale published in 1988. Generally, lack of funding has precluded the production of new mapping activity in Chad.
Soviet military topographic mapping for Chad exists at the following scales: 1:1,000,000 (11 sheets, complete coverage, published 1983-1991); 1:500,000 (32 sheets, complete coverage, published 1979-1989); 1:200,000 (200 sheets, complete coverage, published 1979-1984) and city (1:10,000) topographic map of Ndjamena published in 1976. These products are available in print, digital raster and digital vector GIS formats from East View Geospatial.
The Direction des Recherches Géologiques et Mines (DRGM) is responsible for geological mapping, and a United Nations Development Program funded project started in 1987 to investigate mineral resources. Published mapping was done by the French Bureau de Recherches Géologiques et Minières (BRGM). Chad is included in the Carte géologique de l’Afrique équatoriale et du Cameroun 1:2,000,000, a 1:1,000,000 scale geological sheet of Fort Lamy (now N’Djamena), published in 1956 and of the Nière area at 1:500,000. A study of groundwater resources of the Chad Basin has also been undertaken by BRGM for the Lake Chad Basin Commission.
Germany has aided in the production of soil and hydrological maps of Ouaddaï and Mayo-Kebbi. Using satellite data and IGN maps, 12 thematic maps sheets at 1:200,000 scale have been produced.
The French Institut Français de Recherche Scientifique pour le Développement en Coopération (ORSTOM) has undertaken a wide range of resource mapping. Soil maps at 1:1,000,000 scale cover the country and much of the south is covered by the 32 soil sheets published on topographic sheet lines. A six-sheet, 1:1,000,000 scale gravimetric map was issued in 1968 and vegetation and hydrological maps covering southern areas have also been prepared. Land cover mapping has been undertaken by the Ministry of Water Resources and Forestry.
A study of pastoral agriculture in the Sahelian region was published in 1985 by the Technical Centre for Agricultural and Rural Co-operation (CTA), Wageningen, The Netherlands and the French Département d’Élevage et de Médecine (DEMVT) and contains 1:500,000 scale mapping of grazing potential for central Chad, as well as many smaller scale thematic maps.
A road map of the country at 1:1,500,000 originally published by IGN in two sheets in 1968 was updated for administrative boundaries in 1974, and has been reissued as a single sheet in the Pays et villes du monde series, but has not been revised.