Groundwater provides half of all drinking water worldwide. The impact of climate change on groundwater sources is severely impacting availability and quality in many countries, including Namibia. With a drought emergency declared in 2019 and increasingly extreme weather conditions, annual rainfall may not be sufficient to replenish groundwater resources, according to experts. The growing influx of people living in and moving to the capital Windhoek and to coastal cities is adding to Namibia’s struggle to maintain water supplies.
The IAEA, Namibia’s Ministry of Agriculture, Water and Land Reform and Germany’s Institute of Geosciences and Resources are collaborating to investigate Namibia’s water resources to protect them and make sure water supplies are sufficient year-round. The project will use isotope hydrology techniques (see Science box below) to monitor groundwater resources and to assess the impact of climate change and variability in water from major aquifers in the country’s southwest.
“Using isotopes to assess our groundwater resources is of extreme importance to us for maintaining reliable sources of water throughout the country,” said Anna Kaupuko David, a hydrogeologist at Namibia’s Ministry of Agriculture, Water and Land Reform. Faced with the potential of devastating droughts in her country, Kaupuko David wants to use isotopic techniques to assess if the country’s current plans are sufficient. “If we suffer from a drought, the Windhoek aquifer becomes our emergency water supply for the city and can last at least three years. However, it’s unclear how using the aquifer in this way would impact its future and we’ve been trying to use surface water from our dams to recharge it for times of drought. But with a growing population, it’s never enough,” she said.
Isotope hydrology techniques are a well-established tool for the assessment of groundwater resources and could be the problem solver for Namibia’s droughts, said Ioannis Matiatos, isotope hydrologist at the IAEA. “At the IAEA, we’ve been closely collaborating with experts from all around the world on the use of environmental isotopes to improve the availability and sustainability of freshwater resources.”
