Hydrogeology of Republic of Congo
Most of the textual information on this page was taken from the chapter on the Congo in the report ‘Groundwater in Eastern, Central and Southern Africa’ (UN 1989). This information is outdated. If you have more recent information on the hydrogeology of the Republic of the Congo, please get in touch.
- 1 Compilers
- 2 Terms and conditions
- 3 Geographical Setting
- 4 Geology
- 5 Hydrogeology
- 6 Groundwater Status
- 7 Groundwater use and management
- 8 References
- 9 Return to the index pages
Dr Kirsty Upton and Brighid Ó Dochartaigh, British Geological Survey, UK
Please cite this page as: Upton & Ó Dochartaigh, 2016.
Bibliographic reference: Upton, K. & Ó Dochartaigh, B.É. 2016. Africa Groundwater Atlas: Hydrogeology of the Republic of the Congo. British Geological Survey. Accessed [date you accessed the information]. http://earthwise.bgs.ac.uk/index.php/Hydrogeology_of_Republic_of_Congo
Terms and conditions
The Republic of the Congo lies on the equator. Parts of the country are relatively low lying plain areas, including the Congo Basin, the Niari valley and the coastal plain. Hills and plateaus surround the Congo Basin, and occur in other areas including the northwest and the central part of the country (including the Bateké plateaus), rising to over 800 m. The Mayombe range of mountains and the Chaillu massif also rise to over 800 m.
|Estimated Population in 2013*||4,447,632|
|Rural Population (% of total) (2013)*||35.5%|
|Total Surface Area*||341,500 sq km|
|Agricultural Land (% of total area) (2012)*||31.0%|
|Border Countries||Gabon, Cameroon, Central African Republic, Democratic Republic of the Congo|
|Annual Freshwater Withdrawal (2013)*||46 Million cubic metres|
|Annual Freshwater Withdrawal for Agriculture (2013)*||8.7%|
|Annual Freshwater Withdrawal for Domestic Use (2013)*||69.6%|
|Annual Freshwater Withdrawal for Industry (2013)*||21.7%|
|Rural Population with Access to Improved Water Source (2012)*||38.8%|
|Urban Population with Access to Improved Water Source (2012)*||95.7%|
* Source: World Bank
In the north of the country the climate is equatorial and rain occurs throughout the year, with two slightly less rainy periods from December to February and in July. The centre of the country is a sub-equatorial zone, with two distinct wetter seasons in March/April and October/November. The southwest is a wet tropical zone, with a rainy season that lasts from about October to May, and a dry season from June to September. Total rainfall everywhere is relatively high, at least 1000 mm/year and up to 3000 mm/year in the wettest zones.
Effective precipitation is also high, estimated for the years 1955 to 1970 at between 750 and 1250 mm/year in the coastal basin; 200 to 750 mm/year in the Niari valley and the Congo Basin; and 1000 to 1250 mm/year over the central plateaus.
These maps and graphs were developed from the CRU TS 3.21 dataset produced by the Climatic Research Unit at the University of East Anglia, UK. For more information see the climate resource page.
|There are many major rivers in the Republic of the Congo, in two main basins: the Congo River in the centre and north (which extends over several countries), and the Kouilou-Niari in the southwest. There are also small coastal basins, and the upper part of the Nyanga and Ogouué basins. Most are perennial, owing to the high rainfall and groundwater baseflow.
This section provides a summary of the geology of the Republic of the Congo. More information is available in the report Groundwater in Eastern, Central and Southern Africa: Congo (1989) (see References section, below).
The geology map shows a simplified overview of the geology at a national scale (see the Geology resources page for more details).
This section provides a summary of the hydrogeology of the main aquifers in the Republic of the Congo. More information is available in the report Groundwater in Eastern, Central and Southern Africa: Congo (1989) (see References section, below).
The hydrogeology map shows a simplified overview of the type and productivity of the main aquifers at a national scale (see the Hydrogeology map resource page for more details).
Sedimentary - Intergranular Flow
Sedimentary - Fracture Flow
Recharge to aquifers in the Republic of the Congo is likely to be high, because of high rainfall and the widespread distribution of relatively highly permeable aquifers.
Groundwater use and management
The abundance of surface water in the country means that groundwater is not likely to be very heavily exploited. The town of Pointe-Noire is supplied by groundwater from at least three boreholes. Private industrial groundwater supplies are also used in Pointe-Noire. Programmes of borehole drilling for village water supplies were carried out in the 1980s, including the a FRG-KFW project which constructed 80 boreholes with hand pumps in the Niari region.
In the 1980s, several government agencies were involved in water supply, including the Ministry of Planning (responsible for coordinating drinking water supply); the Department of Agricultural Engineering and Farm Machinery (DGRMA) (responsible for hydro-agricultural development, and also involved in village water supply drilling projects); the National Water and Energy Corporation (SNDE) (responsible for urban water supply); and the Ministry of Energy and Water Supply (established in 1984 and responsible for coordinating the study, exploitation and management of the country's water resources).
Until the late 1980s at least, there had been only a few groundwater studies, including the development of a groundwater supply for the town of Pointe-Noire in the 1950s; a number of local drinking and industrial water supply projects; some studies related to dam construction; and a water resources planning map, with accompanying report of Gabon and Congo published by BRGM and the Comite Interafricain d'Etudes Hydrauliques (CIEH).
The following references provide more information on the geology and hydrogeology of the Republic of the Congo. They can also be accessed through the Africa Groundwater Literature Archive
CIEH/BRGM. 1982. Carte de Planification des Ressources en Eau du Gabon et du Congo; scale: 1 : 1 000 000. Comité Interafricain d'Etudes Hydrauliques, Ouagadougou & Bureau de Recherches Géologiques et Minières (BRGM), Orléans
CIEH/BRGM. 1982. Notice explicative de la carte de planification des ressources en eau du Gabon et du Congo. Serie hydrogeologie de Comite Interafricain d'Etudes Hydrauliques (CIEH), 116 pp, Ouagadougou, Burkina Faso.
United Nations. 1989. Groundwater in Eastern, Central and Southern Africa: Congo. United Nations Department of Technical Cooperation for Development, Natural Resources/Water Series No.19
The reference list in the UN report provides other sources of information, although none are more recent than 1982.
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