What regulations dictate the levels of nutrients allowed in wastewater effluent?

The levels of nutrients allowed in wastewater effluent are primarily dictated by state and federal water quality standards. These standards are established to protect water quality and aquatic life in various bodies of water. At the federal level, the Clean Water Act regulates the discharge of pollutants into waters of the United States, and it includes provisions for managing nutrient levels in effluent. States also have the authority to set their own water quality standards, which must be at least as stringent as federal standards for their specific waters. This dual framework ensures comprehensive oversight of nutrient pollution to mitigate impacts on ecosystems and public health.

Local municipal guidelines may provide additional specific regulations or permits related to nutrient discharge, but they typically operate within the framework of the broader state and federal standards. ISO standards and European Union directives, while relevant in their respective contexts, do not dictate nutrient levels in the United States wastewater effluent specifically.