Also known as the Sungari, the Songhua River stretches 2,308km long, being the largest tributary of the Heilongjiang River and flowing from the Changbai Mountains. The Songhua River has experienced severe pollution, especially due to the 2005 Jilin chemical plant explosions, which created an 80 kilometre long toxic click in the river. Contaminants of concern include beneze, benzopyrene, nitrobenzene, anthracene and pyrene.

Additionally, the Songhua River has been affected by heavy metals, as well as nitrate and nitrite loading. The nitrogen loadings include waste from industrial and municipal wastewater, and agricultural overspill from poorly managed applications of fertiliser.