Water pumps in the developing world used to be made of iron or steel and were hard to manufacture, repair and transport. Thirsty villagers were often forced to wait for outsiders to fix broken parts. Enter Alan Plumtree and Alfred Rudin of the University of Waterloo. Plumtree, a mechanical engineer, and Rudin, a chemist, designed a light-weight, hand-operated plastic pump that is resistant to corrosion and can be easily repaired onsite.
Their pump design is still in use in countries around the world, delivering clean, safe water on demand.