In the pond at Erasmus University Rotterdam, something extraordinary has begun to glow: POND, a luminous installation that makes the health of the water visible. Powered by electricity generated by microbes and using colours that respond to ecological change, this innovative water guardian literally shows how well — or how poorly — the water is doing. “By making water quality visible, I want to give water a voice,” says designer Ermi van Oers of biodesign studio Nova Innova.