Functions of wastewater treatment plants include:
- Sewage treatment – treatment and disposal of human waste, and other household waste liquid from toilets, baths, showers, kitchens, and sinks.
- Industrial wastewater treatment – the treatment of wet wastes from manufacturing industry and commerce including mining, quarrying and heavy industries.
- Agricultural wastewater treatment – treatment and disposal of liquid animal waste, pesticide residues etc. from agriculture.