Blackened rivers snake the ring roads of Beijing, carrying pollution and often smelly water from one end of the city to another. The most polluted of these have been dubbed “foul and filthy” rivers (黑臭河) by China’s Ministry of the Environment (MEP) and Ministry of Housing and Urban-Rural Development (MOHURD). However, the government has decided to clean these up – and is enlisting the help of the public to do so.