Final answer:
Effluent is the treated water that is released into the environment after going through various purification processes at a wastewater treatment facility.
Step-by-step explanation:
Effluent is treated water exiting the wastewater treatment facility. It is often discharged into natural bodies of water such as rivers or oceans. Wastewater treatment involves several stages, including primary treatment to remove solids, secondary treatment to break down organic matter biologically, and sometimes tertiary treatment to further purify the water. Wastewater comes from various sources, including residential, industrial, and agricultural activities. Although effluent is treated, it can still contribute to pollution if released untreated or partially treated.