For 1 week, I worked with a Cambodian organization called Water for Life, which focuses on providing clean drinking water to households in rural Cambodia by making and installing bio-sand filters. These filters are cheap and durable, and reduce E. coli and other bacteria in water by 99.99%, thereby significantly reducing the risk of diarrheal disease, which is the leading cause for death for rural Cambodian people, especially infants. After installing a filter at a young girl's home she watches as clean, clear water pours out.