Difference between revisions of "Hydrogeology of Rwanda"
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| [[File:Rwanda_Geology.png | center | thumb| 500px | Geology of Rwanda at 1:5 million scale.
| [[File:Rwanda_Geology.png | center | thumb| 500px | Geology of Rwanda at 1:5 million scale. map Persits et al. 2002. For more information on the map development and datasets see the [[Geology | geology resource page]].]]
Revision as of 16:27, 20 June 2018
This page has limited information and needs to be updated. If you have more information on the hydrogeology of Rwanda, please get in touch!
Rwanda is a small and relatively densely populated country. Its recent history has been dominated by violence between the related Tutsi and Hutu ethnic groups. Rwanda as a country has been a distinct entity from pre-colonial times. By the mid 18th century, the Kingdom of Rwanda was dominant in the territory, ruled by a Tutsi clan. Tutsis continued to dominate government throughout the colonial period after 1884, supported by the German (as part of German East Africa) and, after 1916, Belgian (as part of Ruanda-Urundi) colonising powers. Ethnic tensions periodically erupted into conflict, including a revolution in 1959. The monarchy was abolished after a colonial referendum in 1961. Rwanda gained independence in 1962, with Hutu now dominating in government. Periodic episodes of violence followed, including a military coup in 1973 and civil war that began in 1990. The most recent notorious and large-scale violence followed during the 1994 genocide, with Rwanda also playing a role in the Congo wars of the later 1990s. In the aftermath of the genocide there was a period of reconciliation and justice with associated improvement in economic, health and social indicators.
The 1990s war and genocide devastated Rwanda’s infrastructure and economy, which had been traditionally based on subsistence agriculture. Tea and coffee cultivation are the major cash crops, facilitated by climate and geography, and are growth agricultural industries. Minerals mining is a significant contributor to export income. The services sector has started to recover after the late 2000s recession, including banking and communications, and particularly tourism, which is now the main source of foreign income and is supported by government. This sector is boosted by the presence of mountain gorillas in uplands areas.
Rwanda has abundant rainfall and both surface water and groundwater resources. Two major river basins cover Rwanda – the Nile and the Congo basins – and there are many lakes and wetlands. Groundwater is the main source of water supply in rural and some urban areas: in mountain areas from springs, and in other areas from boreholes.
- 1 Compilers
- 2 Terms and conditions
- 3 Geographical Setting
- 4 Geology
- 5 Hydrogeology
- 6 References
- 7 Return to the index pages
Dr Kirsty Upton and Brighid Ó Dochartaigh, British Geological Survey, UK
Dr Imogen Bellwood-Howard, Institute of Development Studies
Please cite this page as: Upton, Ó Dochartaigh and Bellwood-Howard, 2018.
Bibliographic reference: Upton K, Ó Dochartaigh BÉ and Bellwood-Howard, I. 2018. Africa Groundwater Atlas: Hydrogeology of Rwanda. British Geological Survey. Accessed [date you accessed the information]. http://earthwise.bgs.ac.uk/index.php/Hydrogeology_of_Rwanda
Terms and conditions
|Border countries||Uganda, Tanzania, Burundi, the Democratic Republic of the Congo|
|Total surface area*||26,340 km2 (2,634,000 ha)|
|Total population (2015)*||11,610,000|
|Rural population (2015)*||8,029,000 (69%)|
|Urban population (2015)*||3,581,000 (31%)|
|UN Human Development Index (HDI) [highest = 1] (2014)*||0.4832|
* Source: FAO Aquastat
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.
In Rwanda, rainfall data are collected by MeteoRwanda. More detailed information on rainfall at a catchment scale is described in the Rwanda Water Resources Master Plan (2014).
|Rwanda is divided into two major river basins: the Nile in the east and centre, and the Congo in the west. Both are shared with neighbouring countries.
Within the Nile and Congo basins in Rwanda, smaller river catchments include the Rusizi and Akanyaru rivers (shared with Burundi); the Akagera River (shared with Tanzania and Burundi); the Muvumba River (shared with Uganda); and Lake Kivu and the Rusizi River (shared with the DRC). There are many smaller lakes, rivers and associated wetlands. The Akagera River, and its tributary the Nyabarongo, are two of the main rivers, both part of the upper Nile basin.
Nine Level 1 surface water catchments have been classified for Rwanda (see RNRA 2014, page 10).
Surface water resources, as other water resources in Rwanda, are managed by the Rwanda Natural Resources Authority-Integrated Water Resource Management Department (RNRA-IWRM).
Surface water monitoring is generally good for the large catchments, but station data often lack absolute topographic reference level; and discharge measurements are often absent or at best out of date. For small catchments, monitoring is less well established (RNRA 2014). Monitoring data are stored in the Rwanda Water Resources Information System (RWRIS). River and lake level and water quality monitoring data from selected monitoring stations can be provided by the RNRA-IWRM. Some information on surface water resources in Rwanda is described in the Rwanda Water Resources Master Plan (2014).
|Rural population with access to safe drinking water (%)||71.9|
|Urban population with access to safe drinking water (%)||86.6|
|Population affected by water related disease||No data||No data||No data||No data|
|Total internal renewable water resources (cubic metres/inhabitant/year)||818.3|
|Total exploitable water resources (Million cubic metres/year)||No data||No data||No data||No data|
|Freshwater withdrawal as % of total renewable water resources||1.128|
|Renewable groundwater resources (Million cubic metres/year)||No data||No data||No data||No data|
|Groundwater produced internally (Million cubic metres/year)||7,000|
|Fresh groundwater withdrawal (primary and secondary) (Million cubic metres/year)|
|Groundwater: entering the country (total) (Million cubic metres/year)||No data||No data||No data||No data|
|Groundwater: leaving the country to other countries (total) (Million cubic metres/year)||No data||No data||No data||No data|
|Industrial water withdrawal (all water sources) (Million cubic metres/year)||20.5|
|Municipal water withdrawal (all water sources) (Million cubic metres/year)||61.4|
|Agricultural water withdrawal (all water sources) (Million cubic metres/year)||102|
|Irrigation water withdrawal (all water sources) 1 (Million cubic metres/year)||No data||No data||No data||No data|
|Irrigation water requirement (all water sources) 1 (Million cubic metres/year)|
|Area of permanent crops (ha)||250,000|
|Cultivated land (arable and permanent crops) (ha)||1,400,000|
|Total area of country cultivated (%)||53.15|
|Area equipped for irrigation by groundwater (ha)||85|
|Area equipped for irrigation by mixed surface water and groundwater (ha)||No data||No data||No data||No data|
These statistics are sourced from FAO Aquastat. They are the most recent available information in the Aquastat database. More information on the derivation and interpretation of these statistics can be seen on the FAO Aquastat website.
Further water and related statistics can be accessed at the Aquastat Main Database.
1 More information on irrigation water use and requirement statistics
The geology map shows a simplified overview of geology at a national scale (see the Geology resource page for more details).
More information is available in the report UN (1988) (see References section, below).
|Alluvium and lake sediments||Quaternary||Unconsolidated alluvial sediments infilling valleys and forming floodplains; and lake sediments. These occur in parts of the Western Rift, along rivers and lakes. Significant outcrops of alluvial sediments occur in the Akagera River floodplain (shown on the map below as the line of Unconsolidated Aquifer along the eastern border of Rwanda). Smaller outcrops of alluvium are also present in river valleys across the rest of the country, but are too small to be shown on this map.|
|Neogene (Cenozoic to recent)||Volcanic rocks crop out in the northwest and southwest of Rwanda.|
|Granites||Palaeoproterozoic||The 'older granites' are seen in eastern Rwanda, along with granitic-gneisses and migmatites|
|Metasedimentary rocks, including Burundian Supergroup||Mesoproterozoic||Metasedimentary rocks, largely quartzites, sandstones, and shales of the Burundian Supergroup, which are locally intruded by granite.|
The hydrogeology map below 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).
Some information on the hydrogeology of Rwanda is available in the report United Nations (1988) (see References section, below).
Groundwater use and management
The Ministry of Environment and the Rwanda Natural Resources Authority (RNRA) have responsibilities for managing water resources in Rwanda. The RNRA, and particularly its Integrated Water Resource Management Department (RNRA-IWRM) is the institution with responsibility for monitoring groundwater resources.
A Rwanda Water Resources Master Plan (2014) contains detailed recommendations for future management of groundwater, including setting up and operating a groundwater monitoring network.
At present there is no systematic groundwater monitoring in Rwanda. Groundwater monitoring data (both levels and quality) are generally only collected during specific, temporary projects (RNRA 2014), such as the development of the Rwanda National Water Master plan, during which a few groundwater stations were monitored temporarily. Groundwater data collected will be stored in the Rwanda Water Resources Information System (RWRIS).
At the moment, therefore, there is not enough information to assess the groundwater resources in Rwanda in terms of total volume available, water levels, essential water quality parameters, or annual recharge assessments, interactions with surface water resources, or current abstraction and used water infiltration rates (RNRA 2014).
In 2005, groundwater was reported to account for 86% of safe drinking water supply in rural areas (Ministry of Natural Resources 2011). In the Eastern and parts of the Southern Province, most people depend on groundwater from boreholes. Extensive borehole drilling and shallow well construction have been done, mostly in the Eastern Province, since 1994. As of 2009, there were at least 400 boreholes and wells in various parts of the country (Ministry of Natural Resources 2011). In upland areas, groundwater from springs is a key resource, including via many piped water supply schemes. Spring supplies can be threatened by deforestation and erosion.
For further information about transboundary aquifers, please see the Transboundary aquifers resources page.
References with more information on the geology and hydrogeology of Rwanda may be accessed through the Africa Groundwater Literature Archive.
Information on Integrated Water Resource Management] in the Rwanda Natural Resources Authority
Rwanda Natural Resources Authority (RNRA). 2014. Consultancy services for development of Rwanda National Water Resources Master Plan. Tender Number 021/RNRA/2011-2012. Master Plan Report: Main Volume. Final Version May 2014. Prepared by SHER Ingénieurs-Conseils s.a.
Rwanda Ministry of Natural Resources. 2011. Water Resources Management Sub-Sector Strategic Plan (2011-2015).
Theunissen K, Hanon M and Fernandez N. 1991. Carte geologique du Rwanda (scale 1:250,000). Service Geologique du Rwanda et Musee Royale de l'Afrique Centrale, Tervuren.
United Nations. 1989. Groundwater in Eastern, Central and Southern Africa: Rwanda. United Nations Department of Technical Cooperation for Development.