Could better groundwater management solve the world’s water problems?
What’s happening? Sub-Saharan Africa has sufficient groundwater to transform its agriculture – while also providing adequate safe water for people’s drinking and hygiene needs – according to Water Aid and the British Geological Survey. The analysis found that most countries in the continent could survive at least five years of drought, and some for over 50 years, on their groundwater reserves. (The Guardian)
Why does this matter? Access to clean and affordable water is a fundamental human right and the basis for functioning human societies. Yet, four billion people across the world experience severe water scarcity at least one month a year and up to 700 million could be displaced as a result of water scarcity by 2030.
Hidden resources – On a global scale, groundwater provides about one-quarter of all the water that we consume, but the use of this resource varies greatly among regions. For example, while 57% of all agricultural land equipped for irrigation in South Asia makes use of groundwater, the percentage drops to just 5% in Sub-Saharan Africa.
This is despite the region having large groundwater reservoirs. Scientists from the British Geological Survey found that every country south of the Sahara has enough groundwater to provide 130 litres of drinking water per person each day without extracting more than 25% of what can be replenished. That includes countries such as Ethiopia and Madagascar, where only half of the population has access to clean drinking water at home. For comparison: Germany consumes 121 litres per day per capita, the UK 141.
Groundwater use has many benefits – Groundwater is less vulnerable to evaporation, pollution, and extreme weather events, which makes it a reliable source of freshwater. UN experts have also said that groundwater is often the most cost-effective way to supply rural communities with drinking water, which is especially important in the context of Africa with its large and dispersed rural population.
In the future, sufficient groundwater supply could also act as a buffer against some of the most severe climate impacts. It can help countries cope with slow onset events, such as precipitation changes and drought, while providing clean water to regions affected by flooding.
What’s needed to unlock the potential? The study says that a lack of investment in infrastructure and equipment prevents many African countries from utilising their natural resources. The researchers also stressed the importance of institutionalised expertise and training to ensure groundwater is extracted and distributed efficiently and fairly – and warned that strong regulations and monitoring are essential to avoid overexploitation and pollution.
A problem of scarcity or inequity? The new research highlights an often-overlooked problem in the discussions around water shortages. While there is a biophysical aspect of water scarcity – it is by definition a finite resource that circulates through the hydrological cycle – water scarcity is often compounded by poor management and unequal distribution.
In California, for example, groundwater pumping used to be unregulated for decades, leading to the rise of a huge agricultural sector reliant on unsustainable levels of water extraction – at the expense of residents whose wells have dried up. Additionally, in South America, local communities are protesting against water-intense and polluting extractive industries, arguing that water allocation should be based on the justice principles of fair distribution, participation and recognition of cultural values.