Climate Change in Ghana: Groundwater

Having visited Ghana, I wanted to assess its groundwater situation to analyse how it could be used it in the future.

Water is obviously vital to humans, with a very strong relationship between access to freshwater and social development/economic growth. As explained by Odada, this relationship is particularly strong in developing regions like Africa. Given this, in Western Africa climate change is expected to result in increased evapotranspiration (increased desertification in Sahel region) and a reduction in rainfall. Therefore, analysing how groundwater can potentially help Ghana in light of these changes is important.

Before I start a brief outline of Ghana. It has a population of 27million, and a Human Development Index (for explanation see here, I think this is a better measure of quality of life than GDP) of 0.573 which ranks 138th in the World. Wikipedia claims that 67% of Ghana speaks English. From my experience this is not even in the right ballpark and has been greatly exaggerated, I'd guess the real percentage was between 10-25%. Ghana is divided into ten administrative regions, which are further divided into 170 districts. Within these districts are significant differences, the largest of which is language. There are eighty different languages spoken within Ghana, of which nine are actually state sponsored. When planning and implementing changes in Ghana, from my own experience, this is a huge hurdle as none of the nine major languages understand each other. I think this lends itself to smaller schemes rather than national ones, which this obviously limits.

Ghana does have a lot of fresh water. The Volta, South Western and Coastal river systems contribute 64.7%, 29% and 6% respectively. As highlighted by Obuobie and Barry, the issue is the spatial and temporal distribution of this water, an issue that I hope resonates throughout my blog as a major challenge for Africa.

In Northern Ghana it doesn't rain for 9months straight. Also, there are issues with health such as polluted surface water sources and disease such as guinea worm. In rural areas and small towns, groundwater sources are increasingly being preferred to surface water. For reasons why, see my post 'Groundwater as a solution?'.

Gyau-Boakye et al. estimate that over 95% of groundwater abstracted in Ghana is used for domestic purposes. This clearly indicates that groundwater is providing vital functions for inhabitants including but not limited to drinking water, cooking and washing. Such groundwater contributes 33% of the total drinking water consumed. As mentioned earlier, there is a spatial unevenness in the distribution of this 33%, as depicted by Obuobie and Barry in the below table:

Population dependent on groundwater for domestic water use.

Accra, the capital, clearly does not make much use of groundwater as it uses the Volta and can control flow using the Akosombo Damn (for more information on the Dam see here). On the other hand, The Upper West and Upper East populations are clearly reliant on the supply of groundwater.

Water is currently abstracted from all geological formations in Ghana, which are depicted below and are all covered by regolith:

Across the country, there are 75000 abstraction systems, 60000 of which are hand-dug wells and 15000 boreholes, with the vast majority of these being safe for multi-purpose use (see p52 for table of issues by area). So far, groundwater appears an excellent option for Ghana with increasingly climate and water variability. But what about the sustainability of the resource?

Groundwater recharge varies across throughout Ghana. Recharge is mainly due to precipitation, with % for each region shown below:

Managing groundwater abstraction sustainably is dependent on understanding the recharge rates and longevity of groundwater resources. Unlike many African countries, such as Nigeria, Ghana actually has a national water policy. As explained by Obuobie and Barry this policy is founded on the principles of the 'Ghana Poverty Reduction Strategy, the Millennium Development Goals and
the “Africa Water Vision” of the New Partnership for Africa’s Development (NEPAD)' (p.60). Furthermore, it dedicates itself to sustainable supply and production of groundwater in Ghana.

The effectiveness of such a policy rides on the quality of policing, regulation and data collection regarding groundwater abstraction. Without such measures, creating a sustainable Ghanaian water supply system using groundwater in light of climate change is unlikely to become reality.

In Ghana groundwater has the potential to help the country grow and give a consistent water supply to its residents, especially those in the Sahelian region. Across West Africa the pressure on current water systems is going to increase through three mechanisms: population increase, wealth increase, and climate change rising evapotranspiration and reducing rainfall. With correct management, Ghana can offset some of these risks by using groundwater.

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