Hydrogeology of Mozambique: Difference between revisions

From MediaWiki
Jump to navigation Jump to search
Line 74: Line 74:
|
|
The country is drained by five principal rivers and several smaller ones. The largest and most important is the Zambezi River. There are four significant lakes: Lake Niassa (or Malawi), Lake Chiuta, Lake Cahora Bassa and Lake Shirwa, all in the north.  
The country is drained by five principal rivers and several smaller ones. The largest and most important is the Zambezi River. There are four significant lakes: Lake Niassa (or Malawi), Lake Chiuta, Lake Cahora Bassa and Lake Shirwa, all in the north.  





Revision as of 11:44, 29 July 2015

Africa Groundwater Atlas >> Hydrogeology by country >> Hydrogeology of Mozambique

Authors

Lucas Chairuca, National Directorate of Water, Mozambique

Arjen Naafs, WaterAid, UK

Ivo van Haren, WE Consult, Mozambique

Kirsty Upton and Brighid Ó Dochartaigh, British Geological Survey, UK


Geographical Setting

Map of Mozambique (For more information on the datasets used in the map see the geography resources section)

General

The Zambezi River divides Mozambique into two topographical regions: to the north, a narrow coastal strip gives way to inland hills and low plateaus; and further west to highland areas including the Niassa, Namuli or Shire, Angonia and Tete highlands and the Makonde plateau. To the south of the Zambezi River, the lowlands cover a larger area inland from the coast, rising to the Mashonaland plateau and Lebombo Mountains located in the deep south.

Estimated Population in 2013* 25,833,752
Rural Population (% of total) (2013)* 68.3%
Total Surface Area* 786,380 sq km
Agricultural Land (% of total area) (2012)* 63.5%
Capital City Maputo
Region Eastern Africa
Border Countries Malawi, South Africa, Swaziland, Tanzania, Zambia, Zimbabwe
Annual Freshwater Withdrawal (2013)* 884.2 Million cubic metres
Annual Freshwater Withdrawal for Agriculture (2013)* 78.0%
Annual Freshwater Withdrawal for Domestic Use (2013)* 19.2%
Annual Freshwater Withdrawal for Industry (2013)* 2.8%
Rural Population with Access to Improved Water Source (2012)* 35%
Urban Population with Access to Improved Water Source (2012)* 80%

* Source: World Bank


Climate

Mozambique has a tropical climate, with a general wet season (October to March) and dry season (April to September). However, local climate varies significantly according to altitude. The highest rainfall is in coastal areas, decreasing to the north and south. Annual precipitation varies from 500 to 900 mm across the country.

Rainfall time-series and graphs of monthly average rainfall and temperature for each individual climate zone can be found on the Mozambique Climate Page.


Average monthly precipitation for Mozambique showing minimum and maximum (light blue), 25th and 75th percentile (blue), and median (dark blue) rainfall Average monthly temperature for Mozambique showing minimum and maximum (orange), 25th and 75th percentile (red), and median (black) temperature Quarterly precipitation over the period 1950-2012 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 resources section.

Surface water

The country is drained by five principal rivers and several smaller ones. The largest and most important is the Zambezi River. There are four significant lakes: Lake Niassa (or Malawi), Lake Chiuta, Lake Cahora Bassa and Lake Shirwa, all in the north.









Surface Water Map of Mozambique (For more information on the datasets used in the map see the surface water resources section)

Soil

Soil Map of Mozambique (For map key and more information on the datasets used in the map see the soil resources section)

Land cover

Land Cover Map of Mozambique (For map key and more information on the datasets used in the map see the land cover resources section)


Geology

This section provides a summary of the geology of Mozambique. More detail can be found in the references listed at the bottom of this page. Many of these references can be accessed through the Africa Groundwater Literature Archive. The geology map on this page shows a simplified version of the geology at a national scale (see the Geology resources page for more details). The map is available to download as a shapefile (.shp) for use in GIS packages.

File:Mozambique Geology.png
Geological Environments
Key Formations Period Lithology Structure
Geological Environment 1
Name of formation1 Time period Description Structure
Geological Environment 2
Geological Environment 3


Hydrogeology

This section provides a summary of the hydrogeology of the main aquifers in Mozambique. More information is available in the references listed at the bottom of this page. Many of these references can be accessed through the Africa Groundwater Literature Archive. 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 Aquifer properties resource page for more details). The map is available to download as a shapefile (.shp) for use in GIS packages.

File:Mozambique Hydrogeology.png 


Unconsolidated

Named Aquifers General Description Water quantity issues Water quality issues Recharge

Sedimentary - Intergranular Flow

Named Aquifers General Description Water quantity issues Water quality issues Recharge

Sedimentary - Intergranular & Fracture Flow

Named Aquifers General Description Water quantity issues Water quality issues Recharge

Sedimentary - Fracture Flow

Named Aquifers General Description Water quantity issues Water quality issues Recharge

Basement

Named Aquifers General Description Water quantity issues Water quality issues Recharge


Groundwater Status

Groundwater quantity

Groundwater quality

Groundwater use and management

Groundwater use

Groundwater management

Groundwater monitoring

Transboundary aquifers

For further information about transboundary aquifers, please see the Transboundary aquifers resources page


References

The following references provide more information on the geology and hydrogeology of Mozambique. These, and others, can be accessed through the Africa Groundwater Literature Archive.

Geology: key references

A revised national geological map was published in 2008, as part of the Mineral Resources Management Capacity Building Project:

Republica de Mocambique - Ministerio dos Recursos Minerais – Direccao Nacional De Geologia. 2008. Carta Geologica Escala 1:1,000,000.

The Map Explanation has 4 volumes:

GTK Consortium. 2006. Carta Geologica Escala 1:1,000,000: Map Explanation, Volume 1. Describes the area south of the Save River

GTK Consortium. 2006. Carta Geologica Escala 1:1,000,000: Map Explanation, Volume 2. Describes the central part of Mozambique.

GTK Consortium. 2006. Carta Geologica Escala 1:1,000,000: Map Explanation, Volume 3. Describes the eastern-central part of Mozambique (Zambezi Province).

GTK Consortium. 2006. Carta Geologica Escala 1:1,000,000: Map Explanation, Volume 4. Describes the western-central part of Mozambique (Tete Province). Report_B6_f1_screen


Hydrogeology: key references

The main source of hydrogeological information for Mozambique is:

Ferro and Bouman / DNA. 1987. Explanatory Notes to the Hydrogeological Map of Mozambique: 1:1,000,000.

This map is largely based on the 1978 national geological map (Afonso 1987), and limited hydrogeological field data. The national geological map was updated in 2008 (see Geology: key references, above), but the 1987 national hydrogeological map has not yet been updated.


Other hydrogeological references are:

African Development Bank. 2002. Mozambique Water and Sanitation Sector Review. Prepared by SEED, May 2002.

African Development Bank. 2005. Rapid Assessment of Rural Water Supply and Sanitation. Mozambique Requirements for Meeting the MDGs, March 2005

British Geological Survey (BGS). 2002. Groundwater Quality: Mozambique.

DNA. 1999. Water resources of Mozambique.

Government of Mozambique (GOM). 1995. Política Nacional de Águas, Resolução do Conselho de Ministros nº 7/95 de 8 de Agosto, Boletim da República no. 34, 1ª Série de 23 de Agosto de 1995.

IWACO. 1986. Study of groundwater to supply Maputo.

Worldbank. 2007. Mozambique Country Water Resources Assistance Strategy: Making Water Work for Sustainable Growth and Poverty Reduction


The DNA (National Water Department), together with donors, particularly UNICEF, have carried out several drilling programs. Drilling reports from these programmes provide lithological information (typically simple but relatively accurate descriptions); borehole information (depth, location filters etc); and hydrogeological information (water levels, main water strikes, some water quality parameters). Proper pumping tests data are rare: most constant discharge tests were less than 1 hour, and in most cases only air-lift tests were done. This information from drilling programmes is not available in one report or single database: the DPOPH (Provincial Departments of Public Works and Housing) have databases with hydrogeological data per province.

Particular drilling programmes were:

ASNANI. 2004-2008. Executed by DNA and financed by ADB. Hundreds of boreholes drilled in Nampula and Niassa Provinces.

MCA (Millenium Challenge Account. 2008-2012. Hundreds of boreholes drilled in Nampula and Cabo Delgado Provinces.

UNICEF One Million Initiative. 2008-2012. Hundreds of boreholes drilled in the Tete, Manica and Sofala Provinces.


Return to the index pages

Africa Groundwater Atlas >> Hydrogeology by country >> Hydrogeology of Mozambique