Final answer:
Sewage treatment facilities use various methods to remove organic matter and pollutants from wastewater, including filtration techniques.
Step-by-step explanation:
Sewage treatment facilities depend on various methods to remove most of the organic matter and pollutants from wastewater. The numerous steps at a conventional sewage treatment plant include pretreatment, primary treatment, secondary treatment, tertiary treatment, disinfection, and either discharge to surface waters or reuse for other purposes.
Filtration methods, such as sand filtration and carbon filtration, may be used to further reduce the organic matter and remove bacteria from the water. The sludge produced during the treatment process is further processed and can be used as energy or fertilizer, and advanced facilities sometimes include methods for stormwater management to prevent untreated sewage from being released into the environment during heavy rain.