The word "sewage" is a noun that refers to the solid and particularly liquid waste that is carried away in a network of drains and sewers. The word is believed to have been taken from the Middle English and derived from the Anglo-Norman word "sewere".
Sewage is however predominantly liquid and is the waste of human settlements and its constituents include urine, faeces, washing water, laundry water, and several other types of liquid and semi-liquid wastes. Sewage is generated from industry and agriculture as well. Sometimes sewage also contains harmful chemical and biological matter that can adversely affect the environment. Untreated sewage when released directly into the river systems or ocean affects the ecology of these natural environments adversely.
The gold mining industry used to release its waste water or sewage containing traces of mercury into rivers and streams. The mines were concentrated in upstream mountainous locations and the mercury used to isolate particles of gold so released was lethal for the local wildlife existing in the rivers.
Sewage is however predominantly liquid and is the waste of human settlements and its constituents include urine, faeces, washing water, laundry water, and several other types of liquid and semi-liquid wastes. Sewage is generated from industry and agriculture as well. Sometimes sewage also contains harmful chemical and biological matter that can adversely affect the environment. Untreated sewage when released directly into the river systems or ocean affects the ecology of these natural environments adversely.
The gold mining industry used to release its waste water or sewage containing traces of mercury into rivers and streams. The mines were concentrated in upstream mountainous locations and the mercury used to isolate particles of gold so released was lethal for the local wildlife existing in the rivers.