Affiliated organisation : WaterAid West Africa
Site of publication : wateraid.org
Type of publication : Report
Date of publication : July 2021
West Africa has experienced a 2°C temperature increase since 1950, and the Sahel region is undoubtedly one of the most vulnerable areas to climate change in the world. The region has significant water resources, and yet access to drinking water and sanitation remains a concern for 40% and 60% of the population respectively. Many people still rely on surface water sources, such as rivers and ponds, which are vulnerable to climate shocks and disasters.
It is expected that the demand for water in the West African region will continue to increase due to population growth, economic development and changes in water consumption by sectors such as agriculture, domestic needs and industry. In a context of rapid urbanization, water supply to large cities will remain one of the main challenges of resource management in West Africa in the years to come.
Thus, Burkina Faso still remains at a more or less low level with a water access rate of 48,7% in 2015, despite the efforts made to increase the level of access to water for the population. Moreover, this rate dropped slightly in 2020 to 47%, which can be probably attributed to rainfall variations.
Niger has enshrined the sustainable management of water resources in its 2010 constitution. Efforts over the past two decades have raised the national rate of access to drinking water to 50% in 2017, but declined in 2020 with an access rate of 47%. However, Niger is still among the countries with the lowest level of access to sanitation in the region, which is partly due to a predominantly rural population spread over a vast territory.
With climate change making rainfall less predictable and flooding more likely, the need to reach everyone with safe WASH services is more urgent than ever. Without climate-resilient services, communities will struggle to adapt to climate change and withstand natural disasters.
Current climate trends in Burkina Faso and Niger
Rainfall in Burkina Faso has shown a downward trend in the number of rainy days index. An increasing trend in the number of consecutive days without rain was also observed. This variability in rainfall is also noted for Niger. Although the trend over the period 1960-2010 indicates a resumption of rainfall surpluses since 1990, the country remains marked by alternating dry and wet winters, which greatly increases the inter-annual variability of rainfall.
In Niger, the spatial distribution of the number of rainy days is highly differentiated. Several parts of the country show an increasing trend in the number of days with cumulative average maximum rainfall. For the period 1991-2000, the rainy season had a late start and an early end with often extreme rainfall breaks, thus constituting “false start” situations for the crops.
In Burkina, long-term observation of temperature extremes indicates an increasing trend in hot days and hot nights, with the exception of the south-western regions where there is a decreasing trend in hot nights. Annual temperature extremes show a general upward trend in both the Sudanian and Sahelian zones. However, this increase is more pronounced for annual minimum temperatures than for annual maximum temperatures.
Niger has enshrined the sustainable management of water resources in its 2010 constitution. Efforts over the past two decades have raised the national rate of access to drinking water to 50% in 2017, but declined in 2020 with an access rate of 47%
Niger is also experiencing an increasing and continuous rise in temperature. During the period 1991-2010, we observe an increase in minimum temperatures of +1.2°C compared to +0.48°C for minimum temperatures.
Two countries in water stress
In the West African Economic and Monetary Union (WAEMU) region, Burkina Faso is the country with the least amount of renewable freshwater. The exploitable water resources in Burkina Faso come solely from surface water, in its current state of degradation and as long as the aquifers are not renewed, groundwater should be treated as useless or even non-renewable resources.
Although 75% of the country is covered by the Sahara Desert and has the lowest average national rainfall in the WAEMU region (190 mm/year), Niger has significant quantities of water resources (groundwater and surface water). However, Niger has a very high dependency index: 89.6%. The country depends mainly on Mali, Burkina Faso and Nigeria and on transboundary flows from the Sokoto River tributary. Although only 2 per thousand of the groundwater is renewed annually, so far the exploitation of these aquifers remains insignificant.
Climate vulnerability: Alarming forecasts
The values adopted by the Government of Burkina Faso in the framework of the National Action Programme for Adaptation to Climate Variability and Change (2015) indicate that the country could experience a temperature increase of 0.8°C on average, and a peak of 1.7°C or even 2.2°C in 2050 over the entire territory of Burkina Faso, although there will be disparities according to the climate domain.
The Sahelian domain will undoubtedly be the most affected, with an average rise of almost 2°C, compared to an average of 1.5°C in the Sudanian domain. The rise in temperature will lead to an increase in extreme climatic phenomena (droughts, floods) and hydro-climatic disasters in terms of frequency and intensity.
Niger’s temperature is projected to increase by 2.0°C to 4.6°C by 2080 compared to pre-industrial levels, with higher temperatures and more extreme temperatures in the southwest of the country. In parallel with the increase in average annual temperatures, the number of very hot days per year (maximum temperature exceeds 35°C) is expected to rise sharply, particularly in the southwest of the country. In some parts of the country, particularly in the south-west, this equates to about 300 very hot days per year by 2080.
Projections for rainfall are less certain than for temperature due to the high natural variability from year to year.
For the period 1991-2000, the rainy season had a late start and an early end with often extreme rainfall breaks, thus constituting “false start” situations for the crops
In Burkina, a small relative decrease in rainfall of -3.4% in 2025 and -7.3% in 2050 is projected. This decrease in rainfall would be coupled with a very high seasonal and interannual variability of climate parameters. In Niger, projections of absolute changes in mean annual rainfall vary greatly from region to region. Of the four climate models on which this analysis is based, one model predicts virtually no change in mean annual rainfall in Niger, one model predicts a decrease, while the other two predict an increase. For Burkina Faso, very significant impacts are expected on major economic sectors such as agriculture, water resources, livestock and forestry, with very considerable socio-economic, health and psychological consequences for vulnerable groups.
What will be the impact on water resources by 2050?
Surface water resources will be weakened by several years of drought, desertification and the resulting silting. Climate change will most likely exacerbate their deterioration.
Climate change will alter the availability of water in many regions. Burkina Faso and Niger are already facing water stress and/or water shortages.
The scarcity of grazing land and water reservoirs will force pastoralists to migrate further and further south. The Sahelian zone is at risk of early drying up of wells and cesspools, low filling of lakes, insufficient water for various uses and worsening water stress.
The most affected sectors are: agriculture (decrease in agricultural production), livestock (fodder deficit), forestry (reduction in the area of forest formations), health (increase in the rate of attack by certain diseases such as measles, meningitis, malaria and respiratory diseases), wildlife and fisheries resources (decrease in fish production, decrease in biological diversity) and water.
Surface water resources will be weakened by several years of drought, desertification and the resulting silting. Climate change will most likely exacerbate their deterioration
The governments of Burkina Faso and Niger took the issue of climate change into account early on in their national policies and strategies.
The water resources sector thus appears to be one of the most vulnerable. West Africa is a region where demographics, economic development and urbanization are continuously increasing, with a growing demand for water. The already high level of water insecurity in West Africa could intensify and threaten economic stability and human development if the countries concerned do not put in place adequate water resource management measures.
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