As Nairobi's population continues to grow, its water supply is no longer sufficient. The Kenyan capital already faces a daily shortfall of hundreds of millions of liters, forcing researchers to search deeper underground for new sources. But what they're discovering is raising difficult questions about pollution, groundwater depletion, and the long-term future of the city's drinking water.

In this report, hydrogeologists, community volunteers and innovators are working to tackle one of the world's biggest sustainability challenges: how to secure sufficient, safe water for a rapidly growing city.

From high-tech airborne surveys and citizen-led water monitoring to wastewater recycling and a bold plan to turn floodwater into a future resource, the story reveals the opportunities and obstacles shaping Nairobi's water future. Could these efforts help create a more water-secure Kenya?