Nilometers: the old-school way of worrying people about water

Nilometers: the old-school way of worrying people about water scarcity. Before grand dams and sensors were a thing, the ancients used nilometers to read and predict water levels. Only rulers and priests were allowed to visit the then-secret structures and use their knowledge of water levels to “predict” floods and impress the citizenry. The three once-prevalent types of nilometers can still be found in Egypt on Cairo’s Rhoda Island, Aswan’s Fiyala Island, and another at the main temple in Kom Ombo, according to Atlas Obscura.