page_title: United States regulation of point source water pollution
section_title: NPDES Permit Program
hierarchical_section_title: United States regulation of point source water pollution / Regulatory framework / Clean Water Act / Direct dischargers / NPDES Permit Program
caption_attribution_description: English: Chart, "Components of all Permits." Description of wastewater discharge permits issued by state environmental agencies and the U.S. Environmental Protection Agency, under the National Pollutant Discharge Elimination System (NPDES) in the United States.
context_page_description: Point source water pollution comes from discrete conveyances and alters the chemical, biological, and physical characteristics of water. In the United States, it is largely regulated by the Clean Water Act. Among other things, the Act requires dischargers to obtain a National Pollutant Discharge Elimination System permit to legally discharge pollutants into a water body. However, point source pollution remains an issue in some water bodies, due to some limitations of the Act. Consequently, other regulatory approaches have emerged, such as water quality trading and voluntary community-level efforts.
context_section_description: The NPDES permit program sets limits on the amount of pollutants that can be discharged into a waterbody. Technology based effluent limits establish a minimum level of pollution controls for all point source discharges. If technology based limits are not sufficient to protect a particular water body, then water quality based effluent limits are developed for facilities discharging to that water body.
  Permits
  Individual states are authorized by the EPA to issue permits when they have demonstrated that their program is at least as stringent as the EPA's program. States perform the day-to-day issuance of permits and oversight of the program while the EPA provides review and guidance to the states.  All NPDES permits must contain a "specific, numeric, measurable set of limits on the amount of various pollutants that can appear in the wastewater discharged by the facility into the nation's waters" as well as guidelines on how often monitoring should be performed and what "sampling and analytic techniques should be used."
  Types of permits
  Individual – A unique permit is issued for each discharger.
  General – A single permit that covers a large number of similar dischargers in a specific geographic area. Examples include the EPA Vessels General Permit and industrial stormwater general permits.
  Permitting process
  The authorized 	permit issuing body receives and reviews the permit application. The technology-based and water quality-based effluent limits are developed and then compared to determine which is the more stringent, which is then used as the effluent limit for the permit. Monitoring requirements, special conditions, and standard conditions for each pollutant are developed and the permit is then issued and its requirements are implemented.
  Technology-based requirements: A minimum level of treatment based on available treatment technologies is required for discharged pollutants, however, a discharger may use any available treatment technologies to meet the limits. The effluent limits are derived from different standards for different discharges:
  Municipal discharges (POTW): National secondary treatment standards define limits of biological treatment standards based on biochemical oxygen demand (BOD), total suspended solids (TSS), and pH balance.
  Industrial and other non-municipal discharges: Limits for many industrial dischargers are based on national standards for issued for specific categories, such as chemical plants, paper mills, and electric power plants (see Effluent guidelines). EPA issues these limitations based on the performance of pollution control and prevention technologies. For existing dischargers, this level of treatment is equivalent to "Best Available Technology Economically Achievable" (BAT) and for new discharges, the treatment level is "New Source Performance Standards" (NSPS). If there is no applicable national standard (effluent guideline regulation) for a particular facility, the NPDES permit agency develops requirements on a case-by-case basis.
  Water quality-based requirements: Should technology-based standards not be stringent enough, Water Quality Based Effluent Limits (WQBEL) are developed to ensure that water quality standards are attained. WQBELs are based on ambient water quality standards.
  Permit components
  All NPDES permits must contain the following five components:
  Cover page – indicates authorization for discharging and its locations
  Effluent limits – limits used to control discharges through technology-based or water quality-based standards
  Monitoring and reporting requirements – used to determine permit compliance
  Special conditions – can be used to supplement effluent limits
  Standard conditions – pre-established conditions that apply to all NPDES permits
  Permit violation
  A permitee can be in violation of their permit when they discharge pollutants at a level higher than what is specified on their permit or discharge without a permit. They can also be in violation if they fail to comply with the monitoring and enforcement portion of the permit.
  Enforcement
  Since the NPDES permit progra
caption: NPDES permit components
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