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National Pollutant Discharge Elimination System (NPDES)

National Pretreatment Program Overview

The national pretreatment program requires nondomestic dischargers that introduce pollutants to Publicly Owned Treatment Works (POTWs) to comply with pretreatment standards to ensure the goals of the Clean Water Act (CWA) are attained. The program also outlines requirements for POTWs to proactively protect its infrastructure while overseeing its management responsibilities.

The objectives of the program are to:

The national pretreatment program identifies specific discharge standards and requirements that apply to sources of nondomestic wastewater discharged to a POTW. By reducing or eliminating waste at the industries (“source reduction”), fewer toxic pollutants are discharged to and treated by the POTWs, providing benefits to both the POTWs and the industrial users.

  • general and specific prohibitions,
  • categorical pretreatment standards, and
  • local limits.