Which agency was empowered by the Clean Water Act (CWA) of 1972 to protect water quality?

The Environmental Protection Agency (EPA) was established under the Clean Water Act (CWA) of 1972 to safeguard and improve the quality of the nation's waters. This legislation provides the EPA with the authority to regulate pollutant discharges into navigable waters and to set water quality standards for all contaminants in surface waters. The EPA plays a crucial role in enforcing regulations designed to protect water resources, ensuring that states adhere to guidelines for maintaining water quality, and issuing permits that govern discharges. This agency serves as the primary federal overseer of water quality management, making it the correct choice in this context.

The other agencies listed, while important in their respective roles, do not have the same direct regulatory authority concerning water quality as the EPA. The Department of Agriculture focuses primarily on farming, forestry, and food-related matters. The Forest Service, part of the U.S. Department of Agriculture, manages national forests and grasslands, but its scope does not include wide-ranging water quality regulations under the CWA. The U.S. Geological Survey is involved in research regarding natural resources, including water, but does not possess the regulatory and enforcement capabilities associated with water quality standards as mandated by the CWA.