An outbreak of chronic kidney disease in rice-growing areas around Anuradhapura and Polannaruwa has been attributed to consumption of ground water polluted by agricultural chemicals. An ongoing cooperative project by the Rotary Clubs of Colombo and eight Rotary Clubs in northwest Ohio, USA will build ten reverse-osmosis units, providing clean drinking water to ten affected communities. Six units are already in operation. The genesis and details of the project will be discussed along with the Science of Reverse Osmosis.