We take water for granted when it flows from our kitchen faucet, but for millions in less developed countries, safe drinking water remains a matter of life and death. Diarrheal diseases kill around two million children every year, and contaminated water is often to blame. In rural areas where pipe infrastructure is too expensive or too hard to maintain, water collection from sources like wells, streams, or springs can take hours each day, a burden that falls primarily on women and young children. And despite the hours of walking time, the sources they must use are often unsafe.

With so…