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Water: Industry Effluent Guidelines

Laws And Regulatory Development

The Clean Water Act (CWA) established the basic structure for regulating discharges of pollutants into the waters of the United States. It provides EPA and the States with a variety of programs and tools to protect and restore the Nation’s waters. These programs and tools generally rely either on water quality-based controls, such as water quality standards and water quality-based permit limitations, or technology-based controls such as effluent guidelines and technology-based permit limitations.

Legal Basis and Core Concepts

Effluent guidelines are one component of the nation’s clean water program, established by the 1972 Clean Water Act. The CWA requires EPA to promulgate effluent guidelines for new categories of dischargers under certain circumstances. See CWA section 304(m)(1)(B) and (C). In addition, the Clean Water Act requires that EPA periodically review existing effluent guidelines, pretreatment standards, and standards of performance for new sources and to revise them "if appropriate" or, in the case of new source performance standards, "as technology and alternatives change". See CWA sections 301(d), 304(b), 304(g)(1), 306(b)(1)(B). In addition, sections 304(e), 308(a), 402(a), and 501(a) of the CWA authorize the Administrator to prescribe BMPs as part of effluent limitations guidelines and standards or as part of a permit.

The national clean water industrial regulatory program is authorized under sections 301, 304, 306 and 307 of the CWA and reflects seven core concepts.

  1. Effluent guidelines are designed to address specific industrial categories. To date, we have promulgated effluent guidelines that address 56 categories—ranging from manufacturing industries such as petroleum refining to service industries such as centralized waste treatment. These regulations apply to between 35,000 and 45,000 facilities that discharge directly to the Nation's waters, as well as another 12,000 facilities that discharge into wastewater treatment plants or publicly owned treatment works (POTWs).
  2. National effluent guidelines typically specify the maximum allowable levels of pollutants that may be discharged by facilities within an industrial category or subcategory. While the limits are based on the performance of specific technologies, they do not generally require the industry to use these technologies, but rather allow the industry to use any effective alternatives to meet the numerical pollutant limits.
  3. Each facility within an industrial category or subcategory must generally comply with the applicable discharge limits — regardless of its location within the country or on a particular water body. See CWA section 307(b) and (c); and CWA section 402(a)(1). The regulations, therefore, constitute a single, standard, pollution control obligation for all facilities within an industrial category or subcategory.
  4. In establishing national effluent guidelines for pollutants, EPA conducts an assessment of (1) the performance of the best pollution control technologies or pollution prevention practices that are available for an industrial category or subcategory as a whole; and (2) the economic achievability of that technology, which can include consideration of costs, benefits, and affordability of achieving the reduction in pollutant discharge.
  5. National regulations apply to three types of facilities within an industrial category:
    • existing facilities that discharge directly to surface waters (i.e., direct discharges) are governed by best practicable technology (BPT), best available technology (BAT), or best conventional pollutant control technology (BCT);
    • existing facilities that discharge to POTWs (indirect dischargers) are governed by pretreatment standards for existing sources (PSES); and
    • newly constructed facilities (new sources) that discharge to surface waters either directly or indirectly are governed by new source performance standards (NSPS) and pretreatment standards for new sources (PSNS).
  6. The use of BMPs, either as an alternative to or to reduce the sampling and analysis to demonstrate compliance with numeric limitations and standards of the final rule, are directed, among other things, at preventing or otherwise controlling leaks, spills, and discharges of toxic and hazardous pollutants.
  7. Finally, the CWA requires an annual review of existing effluent guidelines and, if appropriate, revision of these regulations to reflect changes in the industry and/or changes in available pollution control technologies.

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What are: BPT, BCT, BAT, NSPS, PSNS, PSES?

The various levels of control for different types of discharges are summarized on the Frequently-Asked Questions page.

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Regulatory Development: Laws and Policies

Effluent guidelines are developed within EPA's well-structured Regulatory Development Process, sometimes called the Action Development Process. An overview of how EPA.

EPA abides by several laws and executive orders that guide the process for developing regulations at the federal level. Effluent guidelines generally include a description of each of these laws and orders, along with a summary of EPA's analysis, and a summary of findings. See this overview of the laws and executive orders that govern federal rulemaking.

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