Which act regulates wastewater discharge in the United States?

The Clean Water Act is the primary legislation that regulates wastewater discharge in the United States. This act was enacted to restore and maintain the integrity of the nation's waters by preventing point and nonpoint source pollution. It establishes the framework for regulating discharges of pollutants into the waters of the United States, primarily through the National Pollutant Discharge Elimination System (NPDES) permit program, which requires facilities that discharge wastewater to obtain permits that limit the amount and types of pollutants they can release.

The Clean Water Act aims to safeguard water quality by setting water quality standards and holding dischargers accountable for meeting those standards, thus ensuring that water bodies are safe for fishing, swimming, and other recreational activities. It has played a crucial role in improving the quality of the nation's surface waters and protecting aquatic environments.

In contrast, the other choices focus on different areas of environmental regulation. The Safe Drinking Water Act deals with the quality of drinking water and the protection of public water systems, while the Rivers and Harbors Act primarily governs the control of waterway development and navigation issues. The Clean Air Act addresses air quality and pollution, not water quality. Thus, the Clean Water Act is rightly identified as the key legislation that regulates wastewater discharge in the United States.