Final answer:
Wastewater treatment plants are constructed to handle both domestic and industrial wastes, and the treated wastewater can be reused or returned to the environment.
Step-by-step explanation:
Wastewater treatment plants are usually constructed to handle both domestic and industrial wastes, making the statement true. Wastewater includes sewage as well as water used in industrial and agricultural processes. It is treated in three phases: primary (solid removal), secondary (bacterial decomposition), and tertiary (extra filtration). The treated wastewater may be re-used for irrigation and landscaping, or returned to streams, rivers, and oceans. However, it is important to note that if wastewater is not treated properly, it can become a source of pollution.