Under the Clean Water Act, what is required to discharge pollutants into waters of the United States?

• A. Must have a permit to pollute waters
• B. A license is required to pollute
• C. Permits are optional
• D. Polluting is prohibited entirely

Answer: (A)

Discharging pollutants into waters of the United States requires explicit authorization in the form of a permit. The Clean Water Act uses the National Pollutant Discharge Elimination System (NPDES) permit program to regulate discharges from point sources such as factories and treatment plants. A permit establishes enforceable effluent limits, requires monitoring and reporting, and can include conditions to protect water quality. Without this permit, a discharge is illegal and can lead to enforcement actions. A license is not the term used for this authorization, and permits are not optional for typical discharges—there are exemptions, but in general a permit is the required authorization. In short, controlled discharges are allowed only under a permit.