A innovative water filtration technology using charred rice husks is bringing safe drinking water to thousands of rural Kenyans at a fraction of the cost of conventional systems. Developed through a partnership between Kenyan engineers and international water researchers, the filters utilize rice husks—an abundant agricultural waste product in western Kenya’s rice-growing regions—that are carbonized and combined with clay to create porous ceramic filters. These simple yet effective devices can remove over 99% of bacteria and turbidity from contaminated water sources, addressing a critical public health need in communities where access to treated water remains limited.
The production process creates both environmental and economic benefits. Rice husks, which are typically burned openly or left to decompose, are now being collected from milling stations and converted into a valuable resource. Local artisans, primarily women’s groups, are trained to manufacture the filters using basic equipment, creating sustainable livelihoods while solving a community health challenge. Each filter can produce enough clean water for a family of five for 1-2 years before needing replacement, at a cost of less than $5—making it accessible even to low-income households. Field studies in Homa Bay and Migori counties have documented a significant reduction in waterborne diseases, particularly among children, in communities that have adopted the technology.
The long-term success of this initiative lies in its community-owned model and alignment with circular economy principles. Rather than relying on imported technologies or centralized systems, the filters are produced locally using materials that would otherwise be considered waste. Health extension workers provide education on proper filter use and maintenance, ensuring correct implementation. As climate change increases water scarcity and contamination risks in Kenya, this appropriate technology offers a scalable, sustainable solution that empowers communities to manage their own water security. The model is now being adapted to use other agricultural wastes like coconut husks and maize cobs, demonstrating how locally-sourced materials can solve local challenges while creating economic opportunities in some of Kenya’s most vulnerable regions.