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[[Africa Groundwater Atlas Home | Africa Groundwater Atlas]] >> [[Hydrogeology by country | Hydrogeology by country]] >> Hydrogeology of Senegal
 
[[Africa Groundwater Atlas Home | Africa Groundwater Atlas]] >> [[Hydrogeology by country | Hydrogeology by country]] >> Hydrogeology of Senegal
 
 
  '''Lire cette page en français: [[Hydrogéologie du Sénégal| Hydrogéologie du Sénégal]]''' [[File: flag_of_france.png  | 50px]]
 
 
[[File:CC-BY-SA_logo_88x31.png | frame | This work is licensed under a [https://creativecommons.org/licenses/by-sa/3.0/ Creative Commons Attribution-ShareAlike 3.0 Unported License]]]
 
 
The area of present-day Senegal has been inhabited since prehistoric times. Recorded history shows kingdoms in this area from the 7th century; and parts of Senegal lay within the ancient empires of Ghana and Jolof at times between the 8th and 16th centuries. Islam has been an important influence since the Almovarid era of the 11th century. Various European colonial powers competed for trade in the area from the 15th century, including Portugal, the Netherlands and Britain. From the 17th century France dominated the area as part of French West Africa. In 1960 Senegal gained independence, initially as part of the short-lived Mali Federation with French Sudan (later Mali) and then a few months later as independent Senegal. Between 1982 and 1989, Senegal federated with Gambia as Senegambia. There were sporadic episodes of unrest in the 1980s and 90s, but since 2000 the country has seen relative political and civil stability, although there has been a long-running, albeit relatively low key separatist conflict in the southern Casamance region.
 
 
In the colonial period the economy was dominated by export of groundnuts and other agricultural products. After independence, commercial agriculture was run by government parastatal organisations. From the 1980s there have been moves to privatise and diversify the economy. Senegal’s manufacturing industry is better developed than that of other West African countries, with petrochemicals now playing a significant role in the economy, and Dakar an important international port. Current key exports include fish, chemicals, cotton, groundnuts and calcium phosphate. Tourism is of growing importance, in part due to Senegal’s diverse ecology and culture, its relatively high level of development in comparison with other West African countries, and its reputation as a fairly stable democracy within the region. Information technology based services are another key contributor to the economy.
 
 
Senegal has relatively abundant water resources averaged across the country, but there are strong regional and seasonal variations. The north of the country is semi-arid; the south humid-tropical. The largest surface water resource is the shared Senegal River, which forms the country’s northern boundary. Many smaller perennial rivers and some lakes are also important resources. Groundwater is relatively abundant and provides much of the country’s water supplies. Overabstraction of groundwater is a growing problem in some areas.
 
 
  
 
==Authors==
 
==Authors==
 
 
'''Dr Diakher Hélène Madioune''', Cheikh Anta Diop University, Senegal
 
'''Dr Diakher Hélène Madioune''', Cheikh Anta Diop University, Senegal
  
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'''Professor Serigne Faye''', Cheikh Anta Diop University, Senegal
 
'''Professor Serigne Faye''', Cheikh Anta Diop University, Senegal
  
'''Emily  Crane''', '''Dr Kirsty Upton''', '''Brighid Ó Dochartaigh''', British Geological Survey, UK
+
'''Emily  Crane''', '''Kirsty Upton''', '''Brighid Ó Dochartaigh''', British Geological Survey, UK
 
 
'''Dr Imogen Bellwood-Howard''', Institute of Development Studies, UK
 
  
Please cite this page as: Madioune, Mall, Diaw, Faye, Crane, Upton, Ó Dochartaigh and Bellwood-Howard, 2018.
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Please cite this page as: Madioune, Mall, Diaw, Faye, Crane, Upton & Ó Dochartaigh, 2016.
  
Bibliographic reference: Madione DH, Mall I, Diaw M, Faye S, Crane E, Upton K, Ó Dochartaigh BÉ and Bellwood-Howard, I. 2018. Africa Groundwater Atlas: Hydrogeology of Senegal. British Geological Survey. Accessed [date you accessed the information]. http://earthwise.bgs.ac.uk/index.php/Hydrogeology_of_Senegal
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Bibliographic reference: Madione, D.H., Mall, I., Faye, S., Crane, E., Upton, K. & Ó Dochartaigh, B.É. 2016. Africa Groundwater Atlas: Hydrogeology of Senegal. British Geological Survey. Accessed [date you accessed the information]. http://earthwise.bgs.ac.uk/index.php/Hydrogeology_of_Senegal
  
 
==Terms and conditions==
 
==Terms and conditions==
  
The Africa Groundwater Atlas is hosted by the British Geological Survey (BGS) and includes information from third party sources. Your use of information provided by this website is at your own risk. If reproducing diagrams that include third party information, please cite both the Africa Groundwater Atlas and the third party sources. Please see the [[Africa Groundwater Atlas Terms of Use | Terms of use]] for more information.
+
The Africa Groundwater Atlas is hosted by the British Geological Survey (BGS) and includes information from third party sources. Your use of information provided by this website is at your own risk. If reproducing diagrams that include third party information, please cite both the Africa Groundwater Atlas and the third party sources. Please see the [[Africa Groundwater Atlas Terms and Conditions | Terms and Conditions]] for more information.
  
 
==Geographical Setting==
 
==Geographical Setting==
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===General===
 
===General===
 
 
{| class = "wikitable"
 
{| class = "wikitable"
 
|-
 
|-
|Capital city || Dakar
+
|Estimated Population in 2013* || 14133280
 
|-
 
|-
|Region || Western Africa
+
|Rural Population (% of total)* || 56.92%
 
|-
 
|-
|Border countries || Gambia, Guinea-Bissau, Guinea, Mali, Mauritania
+
|Total Surface Area* || 192530 sq km
 
|-
 
|-
|Total surface area* || 196,710 km<sup>2</sup>  (19,671,000 ha)
+
|Agricultural Land (% of total area)* || 46.82%
 
|-
 
|-
|Total population (2015)* || 15,129,000
+
|Capital City || Dakar
 
|-
 
|-
|Rural population (2015)* || 8,585,000 (57%)
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|Region || Western Africa
 
|-
 
|-
|Urban population (2015)* || 6,544,000 (43%)
+
|Border Countries || Gambia, Guinea-Bissau, Guinea, Mali, Mauritania
 
|-
 
|-
|UN Human Development Index (HDI) [highest = 1] (2014)*|| 0.4659
+
|Annual Freshwater Withdrawal (2013)* || 2.611 Million cubic metres
 +
|-
 +
|Annual Freshwater Withdrawal for Agriculture* || 92.98%
 +
|-
 +
|Annual Freshwater Withdrawal for Domestic Use* || 4.412%
 +
|-
 +
|Annual Freshwater Withdrawal for Industry* || 2.611%
 +
|-
 +
|Rural Population with Access to Improved Water Source* || 60.3%
 +
|-
 +
|Urban Population with Access to Improved Water Source* || 92.5%
 
|}
 
|}
  
<nowiki>*</nowiki> Source: [http://www.fao.org/nr/water/aquastat/data/query/index.html?lang=en FAO Aquastat]
+
<nowiki>*</nowiki> Source: World Bank
  
 
===Climate===
 
===Climate===
  
[[File:Senegal_ClimateZones.png | 375x365px |Koppen Geiger Climate Zones]][[File:Senegal_ClimatePrecip.png | 375x365px |Average Annual Precipitation]][[File:Senegal_ClimateTemp.png | 375x365px |Average Temperature]]
+
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 | climate resource page]].
 +
<gallery widths="375px" heights=365px mode=nolines>
 +
File:Senegal_ClimateZones.png |Koppen Geiger Climate Zones
 +
File:Senegal_ClimatePrecip.png |Average Annual Precipitation
 +
File:Senegal_ClimateTemp.png |Average Temperature
 +
</gallery>
  
[[File:Senegal_pre_Monthly.png| 255x124px| Average monthly precipitation for Senegal showing minimum and maximum (light blue), 25th and 75th percentile (blue), and median (dark blue) rainfall]] [[File:Senegal_tmp_Monthly.png| 255x124px| Average monthly temperature for Senegal showing minimum and maximum (orange), 25th and 75th percentile (red), and median (black) temperature]] [[File:Senegal_pre_Qts.png | 255x124px | Quarterly precipitation over the period 1950-2012]] [[File:Senegal_pre_Mts.png|255x124px | Monthly precipitation (blue) over the period 2000-2012 compared with the long term monthly average (red)]]
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Temporal variations in temperature and rainfall.
 +
Rainfall time-series and graphs of monthly average rainfall and temperature for each individual climate zone can be found on the [[Climate of Senegal | Senegal Climate Page]].  
  
 
+
[[File:Senegal_pre_Monthly.png| 255x124px| Average monthly precipitation for Senegal showing minimum and maximum (light blue), 25th and 75th percentile (blue), and median (dark blue) rainfall]] [[File:Senegal_tmp_Monthly.png| 255x124px| Average monthly temperature for Senegal showing minimum and maximum (orange), 25th and 75th percentile (red), and median (black) temperature]] [[File:Senegal_pre_Qts.png | 255x124px | Quarterly precipitation over the period 1950-2012]] [[File:Senegal_pre_Mts.png|255x124px | Monthly precipitation (blue) over the period 2000-2012 compared with the long term monthly average (red)]]  
More information on average rainfall and temperature for each of the climate zones in Senegal can be seen at the [[Climate of Senegal | Senegal climate page]].
+
 
 
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 | climate resource page]].
 
  
 
===Surface water===
 
===Surface water===
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|}
 
|}
  
===Water statistics===
 
 
{| class = "wikitable"
 
| ||2002||2014||2015
 
|-
 
|Rural population with access to safe drinking water (%) || || || 67.3
 
|-
 
|Urban population with access to safe drinking water (%) || || || 92.9
 
|-
 
|Population affected by water related disease || No data || No data || No data 
 
|-
 
|Total internal renewable water resources (cubic metres/inhabitant/year) || ||1,705 || 
 
|-
 
|Total exploitable water resources (Million cubic metres/year) || No data || No data || No data 
 
|-
 
|Freshwater withdrawal as % of total renewable water resources ||5.70 || ||
 
|-
 
|Total renewable groundwater (Million cubic metres/year) ||  ||3,500 ||
 
|-
 
|Exploitable: Regular renewable groundwater (Million cubic metres/year) || No data || No data || No data 
 
|-
 
|Groundwater produced internally (Million cubic metres/year) || || 3,500|| 
 
|-
 
|Fresh groundwater withdrawal (primary and secondary) (Million cubic metres/year) || No data || No data || No data 
 
|-
 
|Groundwater: entering the country (total) (Million cubic metres/year) || No data || No data || No data 
 
|-
 
|Groundwater: leaving the country to other countries (total) (Million cubic metres/year) || No data || No data || No data 
 
|-
 
|Industrial water withdrawal (all water sources) (Million cubic metres/year) ||58|| ||
 
|-
 
|Municipal water withdrawal (all water sources) (Million cubic metres/year)  ||98|| ||
 
|-
 
|Agricultural water withdrawal (all water sources) (Million cubic metres/year) ||2,065|| ||
 
|-
 
|Irrigation water withdrawal (all water sources) <sup>1</sup> (Million cubic metres/year) || No data || No data || No data 
 
|-
 
|Irrigation water requirement (all water sources) <sup>1</sup> (Million cubic metres/year) ||949.4|| ||
 
|-
 
|Area of permanent crops (ha) || ||68,000 || 
 
|-
 
|Cultivated land (arable and permanent crops) (ha) || ||3,268,000 || 
 
|-
 
|Total area of country cultivated (%) || ||16.61 || 
 
|-
 
|Area equipped for irrigation by groundwater (ha) ||10,000 || || 
 
|-
 
|Area equipped for irrigation by mixed surface water and groundwater (ha) || No data || No data || No data 
 
|}
 
 
These statistics are sourced from [http://www.fao.org/nr/water/aquastat/main/index.stm 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 [http://www.fao.org/nr/water/aquastat/data/query/index.html?lang=en Aquastat Main Database].
 
 
<sup>1</sup> More information on [http://www.fao.org/nr/water/aquastat/water_use_agr/index.stm irrigation water use and requirement statistics]
 
  
 
==Geology==
 
==Geology==
  
This section provides a summary of the geology of Senegal. More detail can be found in the references listed at the bottom of this page. Many of these references can be accessed through the [http://www.bgs.ac.uk/africagroundwateratlas/archive.cfm Africa Groundwater Literature Archive].
+
This section provides a summary of the geology of Senegal. More detail can be found in the references listed at the bottom of this page. Many of these references can be accessed through the [http://www.bgs.ac.uk/africagroundwateratlas/index.cfm Africa Groundwater Literature Archive].
  
 
The geology map on this page shows a simplified overview of the geology at a national scale (see the [[Geology | Geology resource page]] for more details).  
 
The geology map on this page shows a simplified overview of the geology at a national scale (see the [[Geology | Geology resource page]] for more details).  
  
[https://www.bgs.ac.uk/africagroundwateratlas/downloadGIS.html '''Download a GIS shapefile of the Senegal geology and hydrogeology map'''].
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[[File:Senegal_Geology3.png | center | thumb| 500px | Geology of Senegal at 1:5 million scale. Developed from USGS map (Persits et al. 2002). For more information on the map development and datasets see the [[Geology | geology resource page]].]]
 
 
[[File:Senegal_Geology5.png | center | thumb| 400px | Geology of Senegal at 1:5 million scale. Based on map described by Persits et al. 2002/Furon and Lombard 1964. For more information on the map development and datasets see the [[Geology | geology resource page]]. [https://www.bgs.ac.uk/africagroundwateratlas/downloadGIS.html Download a GIS shapefile of the Senegal geology and hydrogeology map].]]
 
  
 
{| class = "wikitable"
 
{| class = "wikitable"
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|
 
|
 
||Quaternary
 
||Quaternary
||Quaternary sediments are not distinguished on the geology map above, but occur in places across the country. Variable deposits including alluvium in river valleys and coastal deposits. Including sand and clay.
+
||Variable deposits including alluvium in river valleys and coastal deposits. Including sand and clay.
 
||Up to 42 m thick.
 
||Up to 42 m thick.
 
|-
 
|-
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==Hydrogeology==
 
==Hydrogeology==
  
This section provides a summary of the hydrogeology of the main aquifers in Senegal.  More information is available in the references listed at the bottom of this page. Many of these references can be accessed through the [http://www.bgs.ac.uk/africagroundwateratlas/archive.cfm Africa Groundwater Literature Archive].
+
This section provides a summary of the hydrogeology of the main aquifers in Senegal.  More information is available in the references listed at the bottom of this page. Many of these references can be accessed through the [http://www.bgs.ac.uk/africagroundwateratlas/index.cfm Africa Groundwater Literature Archive].
  
The hydrogeology map on this page shows a simplified overview of the type and productivity of the main aquifers at a national scale (see the [[Africa Groundwater Atlas Hydrogeology Maps | Hydrogeology map resource page]] for more details).  
+
The hydrogeology map on this page shows a simplified overview of the type and productivity of the main aquifers at a national scale (see the [[Hydrogeology Map | Hydrogeology map resource page]] for more details).  
  
[https://www.bgs.ac.uk/africagroundwateratlas/downloadGIS.html '''Download a GIS shapefile of the Senegal geology and hydrogeology map'''].
+
[[File:Senegal_Hydrogeology3.png | center | thumb| 500px | Hydrogeology of Senegal at 1:5 million scale. For more information on how the map was developed see the [[Hydrogeology Map | Hydrogeology map]] resource page]].
  
[[File:Senegal_Hydrogeology5.png | center | thumb| 600px | Hydrogeology of Senegal at 1:5 million scale. For more information on how the map was developed see the [[Africa Groundwater Atlas Hydrogeology Maps | Hydrogeology map]] resource page. [https://www.bgs.ac.uk/africagroundwateratlas/downloadGIS.html Download a GIS shapefile of the Senegal geology and hydrogeology map].]].
+
====Superficial: Unconsolidated====
 
 
====Unconsolidated Superficial Aquifers====
 
 
{| class = "wikitable"
 
{| class = "wikitable"
 
|Named Aquifers||General Description||Water quantity issues||Water quality issues||Recharge
 
|Named Aquifers||General Description||Water quantity issues||Water quality issues||Recharge
 
|-
 
|-
 
|Superficial aquifer system
 
|Superficial aquifer system
'''Unconsolidated Aquifer: High to Very High Productivity'''
+
||The Superficial aquifer system covers the whole Senegal sedimentary basin. It is dominantly made of sand and sandy clay, which vary in proportion across its extent. The aquifers are intergranular, and the best groundwater potential occurs in sand layers. It comprises the following aquifers: infrabasaltic (occurs below basalts), Thiaroye, Littoral Nord, alluvial, Continental Terminal and Oligo-Miocene aquifers. This aquifer system overlies the more consolidated deposits of the Eocene, Palaeocene, and the Maastrichtian.
||The Superficial aquifer system includes Quaternary and Tertiary sediments. It covers the whole Senegal sedimentary basin. It is dominantly made of sand and sandy clay, which vary in proportion across its extent. The aquifers are intergranular, and the best groundwater potential occurs in sand layers. It comprises the following aquifers: infrabasaltic (occurs below basalts), Thiaroye, Littoral Nord, alluvial (Quaternary); and Continental Terminal and Oligo-Miocene aquifers (Tertiary). This aquifer system overlies more consolidated sediments of the Eocene, Palaeocene, and the Maastrichtian (Tertiary) - described below.
 
  
 
The Superficial aquifer system ranges between 0 to 150 m thick, with a water table depth between a few metres to 72.5 metres depth.  Typical borehole depth varies between 7.6 to 540 m.   
 
The Superficial aquifer system ranges between 0 to 150 m thick, with a water table depth between a few metres to 72.5 metres depth.  Typical borehole depth varies between 7.6 to 540 m.   
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Typical values for aquifer parameters for the Superficial aquifer system are:  
 
Typical values for aquifer parameters for the Superficial aquifer system are:  
  
*Permeability = 1 x 10<sup>-5</sup> to 8.9 x 10<sup>-4</sup> m/s
+
*Permeability = 1 x 10-5 to 8.9 x 10-4 m/s
 
*Transmissivity = 8.64 to 1728 m²/day
 
*Transmissivity = 8.64 to 1728 m²/day
 
*Storage coeffiecient = 0.01-0.15
 
*Storage coeffiecient = 0.01-0.15
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|}
 
|}
  
====Consolidated Sedimentary Aquifers: Cretaceous to Tertiary Intergranular and Fracture Flow====
+
====Cretaceous - Tertiary Sedimentary - Intergranular and Fracture Flow====
 
{| class = "wikitable"
 
{| class = "wikitable"
 
|Named Aquifers||General Description||Water quantity issues||Water quality issues||Recharge
 
|Named Aquifers||General Description||Water quantity issues||Water quality issues||Recharge
 
|-
 
|-
 
|Intermediate aquifer system
 
|Intermediate aquifer system
'''Consolidated Sedimentary Aquifer: High to Very High Productivity'''
+
||The Intermediate aquifer system includes Eocene and Palaeocene formations, and mainly comprises limestone, often karstic or affected by faults.  
||The Intermediate aquifer system lies below the Superficial aquifer system. It includes Eocene and Palaeocene formations (Tertiary), and mainly comprises limestone, often karstic or affected by faults.  
 
  
 
The Eocene aquifer is exploited in the central western part of Senegal and along the Senegal river.  
 
The Eocene aquifer is exploited in the central western part of Senegal and along the Senegal river.  
 
 
The Palaeocene aquifer occurs mainly in western Senegal, around Pout. These aquifers constitute one of the main sources of drinking water for Dakar. The Intermediate aquifer system ranges between 40 to 120 m thick, with a water table depth between a few metres to 102.5 metres depth.  Typical borehole depth varies between 7.6 to 540 m.   
 
The Palaeocene aquifer occurs mainly in western Senegal, around Pout. These aquifers constitute one of the main sources of drinking water for Dakar. The Intermediate aquifer system ranges between 40 to 120 m thick, with a water table depth between a few metres to 102.5 metres depth.  Typical borehole depth varies between 7.6 to 540 m.   
  
 
Typical values for aquifer parameters for the Intermediate aquifer system:
 
Typical values for aquifer parameters for the Intermediate aquifer system:
*Permeability = 1 x 10<sup>-5</sup> to 2.5x10<sup>-8</sup> m/s
+
*Permeability = 1 x 10-5 to 2.5x10-8 m/s
 
*Transmissivity = 1.728 – 9504 m²/day
 
*Transmissivity = 1.728 – 9504 m²/day
 
*Storage coeffiecient = 0.05 -  0.10
 
*Storage coeffiecient = 0.05 -  0.10
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|-
 
|-
 
|Deeper aquifer system
 
|Deeper aquifer system
'''Consolidated Sedimentary Aquifer: High to Very High Productivity'''
+
||The deeper aquifer system, of Maastrichtian age, extends across the whole of the Senegalo-Mauritanian basin and generally consists of sand, sandy-clay and calcareous sandstone. Groundwater storage and flow are largely intergranular. This aquifer constitutes the main source of groundwater supply in Senegal.  It is a transboundary system.
||The deeper aquifer system, of Maastrichtian (Cretaceous) age, extends across the whole of the Senegalo-Mauritanian basin and generally consists of sand, sandy-clay and calcareous sandstone. Groundwater storage and flow are largely intergranular. This aquifer constitutes the main source of groundwater supply in Senegal.  It is a transboundary system.
 
  
 
The deeper aquifer system is about 250 m thick, with a water table depth between a few metres to 140 metres depth.  Typical borehole depth varies between 25 to 680 m. It is typically highly productive, although aquifer properties vary according to local characteristics (lithology, thickness, etc.). Where there are thick clay sequences, the aquifers can be semi-confined or confined. Typical values for aquifer parameters for the deeper aquifer system are:
 
The deeper aquifer system is about 250 m thick, with a water table depth between a few metres to 140 metres depth.  Typical borehole depth varies between 25 to 680 m. It is typically highly productive, although aquifer properties vary according to local characteristics (lithology, thickness, etc.). Where there are thick clay sequences, the aquifers can be semi-confined or confined. Typical values for aquifer parameters for the deeper aquifer system are:
  
*Permeability = 1 x 10<sup>-5</sup> m/s
+
*Permeability = 1 x 10-5 m/s
*Transmissivity = 0.95 – 652,578 m²/day
+
*Transmissivity = 0.95 – 652578 m²/day
*Storage coeffiecient =  1 x 10<sup>-4</sup> – 6 x 10<sup>-4</sup> in the western central part
+
*Storage coeffiecient =  1 x 10-4 – 6 x 10-4  in the western central part
 
*Borehole yield = 80 – 362 m³/h
 
*Borehole yield = 80 – 362 m³/h
 
||Groundwater depletion occurs locally due to overabstraction
 
||Groundwater depletion occurs locally due to overabstraction
 
||High iron, fluoride and salinity seen in the central western part of Senegal. Saline intrusion in the coastal areas.
 
||High iron, fluoride and salinity seen in the central western part of Senegal. Saline intrusion in the coastal areas.
||Recharge occurs from direct rainfall and indirectly from rivers, and is estimated at about 103 x 10<sup>6</sup> m³/a to the Maastrichtian deeper aquifer system. This is mainly recharged in the western central part in Diass horst where formations outcrop, and at the contact with the basement formations and the unconsolidated formations in southeastern part of Senegal.
+
||Recharge occurs from direct rainfall and indirectly from rivers, and is estimated at about 103 x 10^6 m³/a to the Maastrichtian deeper aquifer system. This is mainly recharged in the western central part in Diass horst where formations outcrop, and at the contact with the basement formations and the unconsolidated formations in southeastern part of Senegal.
 
|}
 
|}
  
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Tandia AA, Diop ES and Gaye CB. 1999. Nitrate groundwater pollution in suburban areas: example of groundwater from Yeumbeul, Senegal. Journal of African Earth Sciences, 29(4): 809-822.
 
Tandia AA, Diop ES and Gaye CB. 1999. Nitrate groundwater pollution in suburban areas: example of groundwater from Yeumbeul, Senegal. Journal of African Earth Sciences, 29(4): 809-822.
  
====Basement Aquifers (Hercynian-Panafrican and Birimian) - Low to Moderate Productivity====
+
 
 +
====Basement: Hercynian-Panafrican and Birimian====
 
{| class = "wikitable"
 
{| class = "wikitable"
 
|Named Aquifers||General Description||Water quantity issues||Water quality issues||Recharge
 
|Named Aquifers||General Description||Water quantity issues||Water quality issues||Recharge
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Data show that in 2008 there were at least 7000 recorded groundwater sources in Senegal, both boreholes and large diameter (hand dug) wells, with geological log information for about 1400 of the boreholes.
 
Data show that in 2008 there were at least 7000 recorded groundwater sources in Senegal, both boreholes and large diameter (hand dug) wells, with geological log information for about 1400 of the boreholes.
  
===Groundwater monitoring===
+
=== Groundwater monitoring===
  
 
'''Groundwater levels'''
 
'''Groundwater levels'''
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==References==
 
==References==
  
Many of the references below, and others relating to the hydrogeology of Senegal, can be seen in the [https://www.bgs.ac.uk/africaGroundwaterAtlas/atlas.cfc?method=listResults&title_search=&author_search=&category_search=&country_search=SN&placeboolean=AND&singlecountry=1 African Groundwater Literature Archive].
+
Many of the references below, and others relating to the hydrogeology of Senegal, can be seen in the [http://bgs.ac.uk/africagroundwateratlas/searchResults.cfm?country_search=SN African Groundwater Literature Archive].
  
 
===Key Geology References===
 
===Key Geology References===
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Return to the index pages:
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 +
==Return to the index pages==
 
[[Overview of Africa Groundwater Atlas | Africa Groundwater Atlas]] >> [[Hydrogeology by country | Hydrogeology by country]] >> Hydrogeology of Senegal
 
[[Overview of Africa Groundwater Atlas | Africa Groundwater Atlas]] >> [[Hydrogeology by country | Hydrogeology by country]] >> Hydrogeology of Senegal
 
 
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