A deepening water crisis is unfolding across West Africa, placing millions of lives at risk, according to a new study released by WaterAid and Tree Aid. The report From Roots to Rivers: How Deforestation Impacts Freshwater Access reveals that 45 per cent of people across Ghana, Niger and Nigeria more than 122 million individuals are now exposed to unsafe drinking water. The number has surged by 20 million in just five years.
Forest loss directly tied to shrinking freshwater systems
The study highlights a direct connection between widespread deforestation and the decline of freshwater access. Forests and vegetation help stabilise soil, filter pollutants and regulate rainfall. As these landscapes disappear, the natural systems that maintain safe water supplies are breaking down, affecting drinking water, food production and public health.
Using 12 years of satellite data between 2013 and 2025, researchers tracked changes in vegetation, rainfall and water coverage across the three countries. It is the first analysis to clearly establish a link between deforestation and freshwater decline in the region.
Satellite data reveals alarming patterns
In Niger and Nigeria, the loss of every 1,000 hectares of forest corresponds to an average decline of 9.25 hectares of surface water. Nigeria records a loss of 6.9 hectares, while Niger faces a sharper impact at 11.6 hectares per 1,000 hectares of forest cleared.
In Ghana, the issue is less about water quantity and more about quality, with forest loss causing worsening contamination of freshwater sources.
Climate change intensifying the crisis
The report warns that deforestation and climate change are combining to deepen the crisis. Heavy, unfiltered rainfall in areas without vegetation leads to soil erosion and pollution flowing into rivers, lakes and reservoirs. Over time, this reduces groundwater recharge, cuts down overall water availability and further deteriorates water quality.
Niger faces highest risk
Niger is the worst affected, with 99.5 per cent of its available surface freshwater now considered at risk due to sedimentation and poor quality. In Nigeria, nearly 85.6 million people live in areas highly vulnerable to water loss caused by forest destruction.
Ghana main challenge remains contamination. Between 2013 and 2025, Ghana lost an estimated 298,000 hectares of vegetation roughly an area the size of Edinburgh each year. Nigeria lost around 324,000 hectares annually, equivalent to the size of Birmingham. Niger, however, showed a rare positive trend, gaining about 101,000 hectares of vegetation over the same period.
Call for integrated climate and water policies
The study stresses that West Africa water security cannot be addressed without urgent reforms in forest management. WaterAid and Tree Aid are urging governments to incorporate forest protection and water access into climate action plans and financing strategies.
They emphasised the need for strong, climate-resilient and equitable water services, particularly for vulnerable communities, to ensure universal access to safe drinking water in the face of escalating climate pressures.