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[[Africa Groundwater Atlas Home | Africa Groundwater Atlas]] >> [[Hydrogeology by country | Hydrogeology by country]] >> Hydrogeology of Togo
 
[[Africa Groundwater Atlas Home | Africa Groundwater Atlas]] >> [[Hydrogeology by country | Hydrogeology by country]] >> Hydrogeology of Togo
 
  '''Lire cette page en français: [[Hydrogéologie du Togo | Hydrogéologie du Togo ]]'''  [[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]]]
 
 
In historical times, present-day Togo lay between the powerful kingdoms of Ashanti and Dahomey. From the 11th to 16th centuries, various peoples migrated there from neighbouring regions, including Ewe people from the area of present-day Nigeria, who comprise the majority ethnic group today. European slave trading posts were established on the coast in the 16th century. In the late 19th century German claimed control over what was called Togoland, and after World War I this was claimed and divided by Britain and France. British Togoland voted to join the Gold Coast, becoming independent as part of the nation of Ghana in 1957. French Togoland remained separate and became independent as the Togolose Republic in 1960.
 
A military coup in 1963 replaced an elected government, and another coup in 1967 saw Gnassingbé Eyadéma assume the presidency, maintaining a one-party state until 1991, when under political pressure, opposition parties were legalised. Eyadéma remained in power until he died in 2005, and amidst further unrest was replaced by his son, who has won elections since. Anti-government protests that began in August 2017 have faced government suppression.
 
 
Togo’s economy is based on exports of phosphate and commercial plantation agricultural crops, including coffee, cocoa and groundnuts. The phosphate industry was nationalised in the 1970s, but has declined since the 1990s, in part due to falling world prices and increasing foreign competition. Tourism has become less important to the economy since the 1990s because of political issues.
 
 
Togo has relatively high, but seasonal, rainfall. There are no major rivers in much of the country, and many smaller rivers are ephemeral. Groundwater supplies most public water schemes in the country, including many major cities. Groundwater is also widely used in the phosphate and other industries.
 
 
  
 
==Authors==
 
==Authors==
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'''Kpadja Agouda''', Department of Water Resources, Togo
 
'''Kpadja Agouda''', Department of Water Resources, Togo
 
   
 
   
'''Dr Kirsty Upton''', '''Brighid Ó Dochartaigh''', British Geological Survey, UK
+
'''Kirsty Upton''', '''Brighid Ó Dochartaigh''', British Geological Survey, UK
 
 
'''Dr Imogen Bellwood-Howard''', Institute of Development Studies, UK
 
  
Please cite this page as: Gnazou, Sabi, Tauirou, Akakpo, Agouda, Upton, Ó Dochartaigh and Bellwood-Howard, 2018.
+
Please cite this page as: Gnazou, Sabi, Tauirou, Akakpo, Agouda, Upton & Ó Dochartaigh, 2016.
  
Bibliographic reference: Gnazou MD-T., Sabi EB, Tairou SM, Akakpo W, Agouda K, Upton K, Ó Dochartaigh BÉ and Bellwood-Howard, I. 2018. Africa Groundwater Atlas: Hydrogeology of Togo. British Geological Survey. Accessed [date you accessed the information]. http://earthwise.bgs.ac.uk/index.php/Hydrogeology_of_Togo
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Bibliographic reference: Gnazou, M.D-T., Sabi, E.B., Tairou, S.M., Akakpo, W., Agouda, K., Upton, K. & Ó Dochartaigh, B.É. 2016. Africa Groundwater Atlas: Hydrogeology of Togo. British Geological Survey. Accessed [date you accessed the information]. http://earthwise.bgs.ac.uk/index.php/Hydrogeology_of_Togo
  
 
==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==
  
[[File:Togo_Political.png | right | frame | Togo. Map developed from USGS GTOPOPO30; GADM global administrative areas; and UN Revision of World Urbanization Prospects. For more information on the map development and datasets see the [[Geography | geography resource page]].]]
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[[File:Togo_Political.png | right | frame | Togo (For more information on the datasets used in the map see the [[Geography | geography resources section]])]]  
  
 
===General===
 
===General===
 
Togo is a narrow country extending from the border with Burkina Faso in the north to the Atlantic Ocean (Gulf of Guinea) in the south. The north of the country is dominated by savannah while the coast is generally a low lying plain with numerous lagoons and marshes. The Togo Mountains extend from the south west border with Ghana to the north east border with Benin, reaching a maximum elevation of over 900 m.
 
  
 
{| class = "wikitable"
 
{| class = "wikitable"
 
|-
 
|-
|Capital city || Lome
+
|Estimated Population in 2013* || 6,816,982
 +
|-
 +
|Rural Population (% of total)* || 61%
 
|-
 
|-
|Region || Western Africa
+
|Total Surface Area* || 54.390 sq km
 
|-
 
|-
|Border countries || Benin, Burkina Faso, Ghana
+
|Agricultural Land (% of total area)* || 71%
 
|-
 
|-
|Total surface area* || 56,790 km<sup>2</sup>  (5,679,000 ha)
+
|Capital City || Lome
 
|-
 
|-
|Total population (2015)* || 7,305,000
+
|Region || West Africa
 
|-
 
|-
|Rural population (2015)* ||4,439,000 (61%)
+
|Border Countries || Benin, Burkina Faso, Ghana
 
|-
 
|-
|Urban population (2015)* ||2,866,000 (39%)
+
|Annual Freshwater Withdrawal (2013)* || 169 Million cubic metres
 
|-
 
|-
|UN Human Development Index (HDI) [highest = 1] (2014)*|| 0.4835
+
|Annual Freshwater Withdrawal for Agriculture* || 45%
 +
|-
 +
|Annual Freshwater Withdrawal for Domestic Use* || 53%
 +
|-
 +
|Annual Freshwater Withdrawal for Industry* || 2%
 +
|-
 +
|Rural Population with Access to Improved Water Source* || 40%
 +
|-
 +
|Urban Population with Access to Improved Water Source* || 91%
 
|}
 
|}
  
<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===
 +
 +
Togo is a narrow country extending from the border with Burkina Faso in the north to the Atlantic Ocean (Gulf of Guinea) in the south. The north of the country is dominated by savannah while the coast is generally a low lying plain with numerous lagoons and marshes. The Togo Mountains extend from the south west border with Ghana to the north east border with Benin, reaching a maximum elevation of over 900 m.
 +
  
 
The climate of Togo is classified as Tropical Savannah. Annual average temperatures are slightly higher in the north and lower in the south. They also decrease with altitude in the mountainous regions. Precipitation is generally lower in the north and higher in the south but also increases slightly over the mountainous regions.
 
The climate of Togo is classified as Tropical Savannah. Annual average temperatures are slightly higher in the north and lower in the south. They also decrease with altitude in the mountainous regions. Precipitation is generally lower in the north and higher in the south but also increases slightly over the mountainous regions.
 +
 +
 +
<gallery widths="375px" heights=365px mode=nolines>
 +
File:Togo_ClimateZones.png |Koppen Geiger Climate Zones
 +
File:Togo_ClimatePrecip.png |Average Annual Precipitation
 +
File:Togo_ClimateTemp.png |Average Temperature
 +
</gallery>
 +
  
 
Precipitation and temperature vary throughout the year. Average temperature across the country shows two peaks throughout year in March and November. When averaged spatially across the country, precipitation shows a relatively wet period between April and October; however this is split into two distinct wet seasons in the south of the country, which occur during April-July and September-October.
 
Precipitation and temperature vary throughout the year. Average temperature across the country shows two peaks throughout year in March and November. When averaged spatially across the country, precipitation shows a relatively wet period between April and October; however this is split into two distinct wet seasons in the south of the country, which occur during April-July and September-October.
  
[[File:Togo_ClimateZones.png | 375x365px |Koppen Geiger Climate Zones]][[File:Togo_ClimatePrecip.png | 375x365px |Average Annual Precipitation]][[File:Togo_ClimateTemp.png | 375x365px |Average Temperature]]
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[[File:Togo_pre_Monthly.png| 255x124px| Average monthly precipitation for Togo showing minimum and maximum (light blue), 25th and 75th percentile (blue), and median (dark blue) rainfall]] [[File:Togo_tmp_Monthly.png| 255x124px| Average monthly temperature for Togo showing minimum and maximum (orange), 25th and 75th percentile (red), and median (black) temperature]] [[File:Togo_pre_Qts.png | 255x124px | Quarterly precipitation over the period 1950-2012]] [[File:Togo_pre_Mts.png|255x124px | Monthly precipitation (blue) over the period 2000-2012 compared with the long term monthly average (red)]]
 +
 +
For further detail on the climate datasets used see the [[Climate | climate resources section]].
  
[[File:Togo_pre_Monthly.png| 255x124px| Average monthly precipitation for Togo showing minimum and maximum (light blue), 25th and 75th percentile (blue), and median (dark blue) rainfall]] [[File:Togo_tmp_Monthly.png| 255x124px| Average monthly temperature for Togo showing minimum and maximum (orange), 25th and 75th percentile (red), and median (black) temperature]] [[File:Togo_pre_Qts.png | 255x124px | Quarterly precipitation over the period 1950-2012]] [[File:Togo_pre_Mts.png|255x124px | Monthly precipitation (blue) over the period 2000-2012 compared with the long term monthly average (red)]]
 
 
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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| [[File:Togo_Hydrology.png | frame | Major surface water features of Togo. Map developed from World Wildlife Fund HydroSHEDS; Digital Chart of the World drainage; and FAO Inland Water Bodies. For more information on the map development and datasets see the [[Surface water | surface water resource page]].]]
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| [[File:Togo_Hydrology.png | frame | Major surface water features of Togo (For more information on the datasets used in the map see the [[Surface water | surface water resources section]])]]
|
 
 
|}
 
|}
  
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{|
 
{|
 
|-
 
|-
 +
| [[File:Togo_soil.png | frame | Soil Map of Togo (For more information on the datasets used in the map see the [[Soil | soil resources section]])]]
 +
 
|Clay-rich Lixosols, which are common in the northern part of Togo, generally reflect stable geological conditions and natural savannah vegetation.  
 
|Clay-rich Lixosols, which are common in the northern part of Togo, generally reflect stable geological conditions and natural savannah vegetation.  
  
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Fluvisols have developed along the valley of the River Oti in the north and the River Zio in the south.
 
Fluvisols have developed along the valley of the River Oti in the north and the River Zio in the south.
 
| [[File:Togo_soil.png | frame | Soil Map of Togo, from the European Commission Joint Research Centre: European Soil Portal. For more information on the map see the [[Soil | soil resource page]].]]
 
|
 
 
|}
 
|}
  
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|-
 
|-
 
|
 
|
| [[File:Togo_LandCover.png | frame | Land Cover Map of Togo, from the European Space Agency GlobCover 2.3, 2009. For more information on the map see the [[Land cover | land cover resource page]].]]
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| [[File:Togo_LandCover.png | frame | Land Cover Map of Togo (For more information on the datasets used in the map see the [[Land cover | land cover resources section]])]]
|
 
 
|}
 
|}
  
===Water statistics===
 
  
{| class = "wikitable"
 
| || 1996 ||2002||2005||2014||2015
 
|-
 
|Rural population with access to safe drinking water (%) || || ||  || || 44.2
 
|-
 
|Urban population with access to safe drinking water (%) || || ||  || || 91.4
 
|-
 
|Population affected by water related disease || No data || No data || No data  || No data || No data
 
|-
 
|Total internal renewable water resources (cubic metres/inhabitant/year) || || ||  ||1574 ||
 
|-
 
|Total exploitable water resources (Million cubic metres/year) || No data || No data || No data  || No data || No data
 
|-
 
|Freshwater withdrawal as % of total renewable water resources || ||1.15 || || ||
 
|-
 
|Total renewable groundwater (Million cubic metres/year) ||  || || ||5,700 ||
 
|-
 
|Exploitable: Regular renewable groundwater (Million cubic metres/year) || No data || No data || No data  || No data || No data
 
|-
 
|Groundwater produced internally (Million cubic metres/year) || || ||  ||5,700 ||
 
|-
 
|Fresh groundwater withdrawal (primary and secondary) (Million cubic metres/year) || No data || No data || No data  || No data || No data
 
|-
 
|Groundwater: entering the country (total) (Million cubic metres/year) || No data || 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 || No data
 
|-
 
|Industrial water withdrawal (all water sources) (Million cubic metres/year) || || ||6.3|| ||
 
|-
 
|Municipal water withdrawal (all water sources) (Million cubic metres/year)  || || ||140.7|| ||
 
|-
 
|Agricultural water withdrawal (all water sources) (Million cubic metres/year) || || 76|| || ||
 
|-
 
|Irrigation water withdrawal (all water sources) <sup>1</sup> (Million cubic metres/year) || ||46||  || ||
 
|-
 
|Irrigation water requirement (all water sources) <sup>1</sup> (Million cubic metres/year) ||6.6 || ||  || ||
 
|-
 
|Area of permanent crops (ha) || || ||  ||170,000 ||
 
|-
 
|Cultivated land (arable and permanent crops) (ha) || || ||  ||2,820,000 ||
 
|-
 
|Total area of country cultivated (%) || || ||  || 49.66||
 
|-
 
|Area equipped for irrigation by groundwater (ha) || No data || No data || No data  || No data || No data
 
|-
 
|Area equipped for irrigation by mixed surface water and groundwater (ha) || No data || No data || 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 Togo. 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 Togo. 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 version of the geology at a national scale (see [[Geology | the Geology resources page]] for more details).  
 
 
[https://www.bgs.ac.uk/africagroundwateratlas/downloadGIS.html '''Download a GIS shapefile of the Togo geology and hydrogeology map'''].
 
 
   
 
   
  
[[File:Togo_Geology4.png | center | thumb| 500px | Geology of Togo 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 Togo geology and hydrogeology map].]]
+
[[File:Togo_Geology2.png | center | border | 500px]]
  
 
{| class = "wikitable"
 
{| class = "wikitable"
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|Key Formations||Period||Lithology||Structure
 
|Key Formations||Period||Lithology||Structure
 
|-
 
|-
!colspan="4"| Coastal Basin Sedimentary
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!colspan="4"| Sedimentary – Coastal Basin
 
|-
 
|-
 
|Coastal Basin
 
|Coastal Basin
||Cretaceous – Pleistocene (Quaternary)
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||Cretaceous – Pleistocene  
 
||Basal unconsolidated sands, limestone, marl, phospharenite, continental sediments and Quaternary sands.  
 
||Basal unconsolidated sands, limestone, marl, phospharenite, continental sediments and Quaternary sands.  
 
||Sequence deposited in a compartment of the Adina Fault in the south of Togo.
 
||Sequence deposited in a compartment of the Adina Fault in the south of Togo.
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|}
 
|}
 +
  
 
==Hydrogeology==
 
==Hydrogeology==
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This section provides a summary of the hydrogeology of the main aquifers in Togo.  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].
 
This section provides a summary of the hydrogeology of the main aquifers in Togo.  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 version 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 Togo geology and hydrogeology map'''].
 
  
 
There are three main hydrogeological environments in Togo:
 
There are three main hydrogeological environments in Togo:
  
 +
*Basement aquifers, including the West African Craton and Dahomeyides Chain
 +
*The Volta Basin aquifer
 
*Coastal Sedimentary aquifers
 
*Coastal Sedimentary aquifers
*The Volta Basin aquifer
 
*Basement aquifers, including the West African Craton and Dahomeyides Chain
 
  
 
The basement aquifers and Volta Basin aquifer represent 94% of the area of Togo. The basement is predominantly composed of low permeability granite, gneiss and migmatite and groundwater occurs in the weathered horizon or fractures. The Volta Basin comprises sandstone and quartzite while the Coastal Basin is a layered sedimentary sequence that dips gently from north to south.  
 
The basement aquifers and Volta Basin aquifer represent 94% of the area of Togo. The basement is predominantly composed of low permeability granite, gneiss and migmatite and groundwater occurs in the weathered horizon or fractures. The Volta Basin comprises sandstone and quartzite while the Coastal Basin is a layered sedimentary sequence that dips gently from north to south.  
  
  
[[File:Togo_Hydrogeology4.png | center | thumb| 500px | Hydrogeology of Togo 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 Togo geology and hydrogeology map].]].
+
[[File:Togo_Hydrogeology2.png | center | border | 500px]]
  
  
====Sedimentary Aquifers - Intergranular and Fracture Flow====
+
====Sedimentary - Intergranular//Fracture ====
  
The coastal basin sedimentary aquifer (Keta Basin) is a multi-layered aquifer, which generally has high productivity and groundwater potential. Intergranular flow dominates in the shallower systems, but fracture flow is important at depth. The coastal basin contains the following aquifers in a layered system:
+
The coastal basin sedimentary aquifer (Keta Basin) is a multi-layered aquifer. Intergranular flow dominates in the shallower systems, but fracture flow is important at depth. The coastal basin contains the following aquifers in a layered system (see cross section):
  
 
*Quaternary Sand Aquifer
 
*Quaternary Sand Aquifer
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*Maestrichtian Aquifer
 
*Maestrichtian Aquifer
  
These aquifers are separated by thick, low permeability aquicludes.
+
These aquifers are separated by thick aquicludes.
  
  
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| Quaternary Sand Aquifer
 
| Quaternary Sand Aquifer
 
||This forms a 2-3km wide aquifer along the coast and is typically exploited by wells for domestic use. Flow is predominantly intergranular and the aquifer is unconfined.  
 
||This forms a 2-3km wide aquifer along the coast and is typically exploited by wells for domestic use. Flow is predominantly intergranular and the aquifer is unconfined.  
The properties of this aquifer are largely unknown. The aquifer thickness varies from 10 - 30 m and the water table depth varies from 0.5 - 3 m.  
+
The properties of this aquifer are largely unknown, however the aquifer thickness varies between 10 and 30 m and the water table depth varies between 0.5 and 3 m.  
 
||
 
||
 
||
 
||
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|-
 
|-
 
| Continental Terminal Aquifer
 
| Continental Terminal Aquifer
|| This is the most heavily exploited aquifer in the coastal basin, providing the drinking water supply for the city of Lome. Flow is predominantly intergranular and the aquifer is unconfined. Transmissivity is typically on the order of 10-³ – 10<sup>-2</sup> m²/s. Storage is typically 1-8%. Borehole yields generally vary between 10 and 200 m³/h.
+
|| This is the most heavily exploited aquifer in the basin, providing the drinking water supply for the city of Lome. Flow is predominantly intergranular and the aquifer is unconfined. Transmissivity is typically on the order of 10-³ – 10-2 m²/s. Storage is typically 1-8%. Borehole yields generally vary between 10 and 200 m³/h.
  
 
The aquifer thickness varies between 20 and 80 m, the water table depth varies between 1.5 and 50 m, and boreholes are generally drilled to depths of 10-60 m.
 
The aquifer thickness varies between 20 and 80 m, the water table depth varies between 1.5 and 50 m, and boreholes are generally drilled to depths of 10-60 m.
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*pH values vary between 6.7 and 7.6
 
*pH values vary between 6.7 and 7.6
  
||Recharge occurs in the north of the basin by infiltration through the Continental Terminal aquifer.
+
|| Recharge occurs in the north of the basin by infiltration through the Continental Terminal aquifer.
  
 
|-
 
|-
|Maestrichtian Aquifer
+
| Maestrichtian Aquifer
||The Maestrichtian Aquifer comprises sandstone (and sometimes sandy limestone) and flow is predominantly intergranular. It is mainly exploited in the northern part of the basin where it is more easily accessible, although it remains confined across the basin. The lateral extent of this aquifer towards the south of the basin is currently unknown due to the significant depth of the sediments.  
+
|| The Maestrichtian Aquifer comprises sandstone (and sometimes sandy limestone) and flow is predominantly intergranular. It is mainly exploited in the northern part of the basin where it is more easily accessible, although it remains confined across the basin. The lateral extent of this aquifer towards the south of the basin is currently unknown due to the significant depth of the sediments.  
  
Transmissivity is typically on the order of 10<sup>-3</sup> – 10<sup>-2</sup> m²/s. Storage is typically 1-3%. Borehole yields generally vary between 15 and 140 m³/h. The aquifer thickness varies between 5 and 25 m and boreholes are generally drilled to depths of 80-150 m (these would need to be significantly deeper in the southern part of the basin).
+
Transmissivity is typically on the order of 10-3 – 10-2 m²/s. Storage is typically 1-3%. Borehole yields generally vary between 15 and 140 m³/h. The aquifer thickness varies between 5 and 25 m and boreholes are generally drilled to depths of 80-150 m (these would need to be significantly deeper in the southern part of the basin).
  
 
||
 
||
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|}
 
|}
  
====Sedimentary Aquifers - Fracture Flow====
+
====Consolidated Sedimentary - 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
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====Basement Aquifers====
+
====Basement====
 
{| 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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|West African Craton and Dahomeyides Chain
 
|West African Craton and Dahomeyides Chain
  
||The West African Craton (north of Dapaong) and the Dahomeyides Chain are the principal groundwater-bearing formations of the basement. However, these are generally discontinuous aquifers, either related to fracturing or alteration/weathering of the bedrock.
+
|| The West African Craton (north of Dapaong) and the Dahomeyides Chain are the principal groundwater-bearing formations of the basement. However, these are generally discontinuous aquifers, either related to fracturing or alteration/weathering of the bedrock.
  
 
The properties of the basement aquifers are controlled by the frequency of fracturing, which varies depending on the nature of the rock, bedding, structural position and tectonic history. Harder rocks are generally more fractured, while schistose rocks are more deformable and therefore less fractured.
 
The properties of the basement aquifers are controlled by the frequency of fracturing, which varies depending on the nature of the rock, bedding, structural position and tectonic history. Harder rocks are generally more fractured, while schistose rocks are more deformable and therefore less fractured.
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The main institutions responsible for groundwater supply and management in Togo are:
 
The main institutions responsible for groundwater supply and management in Togo are:
  
;Le Ministère de l’Eau, de l’Assainissement et de l’Hydraulique Villageoise (MEAHV) (Ministry of Water, sanitation and village hydraulics)
+
;Le Ministère de l’Eau, de l’Assainissement et de l’Hydraulique Villageoise (MEAHV)
 +
:Ministry of Water, sanitation and village hydraulics
 +
:Responsible for the implementation of national policy related to water and sanitation, and for monitoring in collaboration with other ministries or institutions
  
Responsible for the implementation of national policy related to water and sanitation, and for monitoring in collaboration with other ministries or institutions.
+
;La Société Togolaise des Eaux (TdE)
 +
:Togolese Company of Water
 +
:Responsible for supplying the greatest possible number of urban households at the lowest possible cost, and for ensuring the collection and disposal of waste water in urban centres where the equipment exists
  
;La Société Togolaise des Eaux (TdE) (Togolese Company of Water)
+
;La Société de patrimoine Eau, Assainissement Urbain (SP-EAU)
 +
:Heritage Society of Water and Urban Sanitation
 +
:Ensures the management and development of state-controlled drinking water supply and sanitation in urban areas
  
Responsible for supplying the greatest possible number of urban households at the lowest possible cost, and for ensuring the collection and disposal of waste water in urban centres where the equipment exists.
+
=== Transboundary aquifers===
  
;La Société de patrimoine Eau, Assainissement Urbain (SP-EAU) (Heritage Society of Water and Urban Sanitation)
+
Togo shares the sedimentary coastal aquifer with Ghana, Benin and Nigeria but to date there are no significant transboundary issues.
  
Ensures the management and development of state-controlled drinking water supply and sanitation in urban areas.
+
For further information about transboundary aquifers, please see the [[Transboundary aquifers | Transboundary aquifers resources page]]
  
 
=== Groundwater monitoring===
 
=== Groundwater monitoring===
  
 
The Department of Water Resources, which sits within the Ministry of Water, is responsible for groundwater monitoring. However, there are currently no national groundwater level or groundwater quality monitoring programmes.
 
The Department of Water Resources, which sits within the Ministry of Water, is responsible for groundwater monitoring. However, there are currently no national groundwater level or groundwater quality monitoring programmes.
 
=== Transboundary aquifers===
 
 
Togo shares the sedimentary coastal aquifer with Ghana, Benin and Nigeria but to date there are no significant transboundary issues.
 
 
For further information about transboundary aquifers, please see the [[Transboundary aquifers | Transboundary aquifers resources page]]
 
 
  
 
==References==
 
==References==
Many of the references below, and others relating to the hydrogeology of Togo, can be found in the [https://www.bgs.ac.uk/africaGroundwaterAtlas/atlas.cfc?method=listResults&title_search=&author_search=&category_search=&country_search=TG&placeboolean=AND&singlecountry=1 Africa Groundwater Literature Archive].
+
Many of the references below, and others relating to the hydrogeology of Togo, can be found in the [http://www.bgs.ac.uk/africagroundwateratlas/searchResults.cfm?title_search=&author_search=&category_search=&country_search=TG&placeboolean=AND&singlecountry=1 Africa Groundwater Literature Archive].
  
 
===Key Geology References===
 
===Key Geology References===
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[[Category:Hydrogeology by country|t]]
 
[[Category:Hydrogeology by country|t]]
[[Category:Africa Groundwater Atlas]]
 

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