568 F.2d 1369 (D.C. Cir. 1977)
Natural Resources Defense Council, Inc. v.
Whether EPA has statutory authority under the Clean Water Act to promulgate regulations categorically exempting entire classes of point source discharges (such as municipal and industrial storm sewer discharges) from the NPDES permitting requirement on grounds of administrative necessity and program manageability.
Under Clean Water Act § 301(a), 33 U.S.C. § 1311(a), the discharge of any pollutant by any person is unlawful except in compliance with the Act, including the NPDES permit program under § 402, 33 U.S.C. § 1342. A "point source" is defined broadly in § 502(14), 33 U.S.C. § 1362(14). EPA may not, by regulation, create categorical exemptions from NPDES coverage for classes of point sources beyond those express exemptions enacted by Congress. Although EPA cannot nullify the statutory permit requirement, it retains administrative flexibility to implement the program through tools such as general or area-wide permits, prioritization, phased scheduling, and enforcement discretion, so long as those tools do not contravene the Act's text and purposes.
EPA lacks authority to categorically exempt classes of point source discharges from the NPDES permitting requirement. The court vacated EPA's regulatory exemptions and remanded. At the same time, the court recognized that EPA may employ general (or area-wide) permits and other administrative mechanisms to manage the program within statutory bounds.
NRDC v. Costle is a cornerstone of environmental and administrative law. Substantively, it cements the principle that EPA cannot rewrite the Clean Water Act by exempting categories of point sources from NPDES permitting absent explicit congressional authorization. Administratively, it legitimizes and encourages the use of general and area-wide permits, prioritization, and staged implementation—tools that today are ubiquitous, especially in the stormwater context (e.g., municipal separate storm sewer systems and multi-sector industrial stormwater general permits). The decision also illustrates the judiciary's role in maintaining the separation of legislative and executive functions: resource constraints and policy preferences cannot override unambiguous statutory commands. For law students, the case offers a pre-Chevron example of textual and structural statutory interpretation, the limits of "administrative necessity," and a practical template for how courts can enforce statutory rigor while facilitating feasible program administration.