United States Supreme Court Adopts a “Functional Equivalent” Standard for Discharge of Pollutants to Groundwater


On April 23, 2020, the U.S. Supreme Court issued a significant and long awaited Clean Water Act (CWA) decision in County of Maui v. Hawaii Wildlife Fund et al., adopting a new standard, the “functional equivalent” standard, to determine whether discharge of pollutants to groundwater is considered a point source discharge requiring a federal National Pollutant Discharge Elimination System (NPDES) permit.  The Court chose a middle ground, declining to adopt either the more expansive “fairly traceable” standard used by the Ninth Circuit or the more limited standard advocated by Maui County and the U.S. EPA-that no permit is required unless a point source directly discharges into navigable water (also known under the CWA as a “water of the United States”).

As background, the CWA is a federal law forbidding the “addition” of any pollutant from a “point source” to “navigable waters” without a permit from the EPA (or a state agency with a delegated program, which in California are the State and Regional Water Boards). It defines “point source” as “. . . any discernible, confined and discrete conveyance, including but not limited to any pipe, ditch, channel, tunnel, conduit, well, discrete fissure, container, rolling stock, concentrated animal feeding operation, or vessel or other floating craft, from which pollutants are or may be discharged.”

Maui County, pumps partially treated sewage underground, where it travels about half a mile through groundwater to the ocean. Maui County does not have a permit for discharges into navigable waters, and environmental groups sued claiming that it should. The U.S. Court of Appeals for the Ninth Circuit held that a permit is required for non-direct discharges that “are fairly traceable from the point source to navigable water.”

The Supreme Court vacated that decision by a 6-3 vote. In so doing, it rejected the Ninth Circuit’s “fairly traceable” standard, noting that “virtually all water, polluted or not, eventually makes its way to navigable water,” and held that Congress did not intend for the EPA to have “permitting authority over the release of pollutants that reach navigable waters many years after their release and in highly diluted forms” - especially because the relevant provisions of the CWA “say nothing at all about nonpoint source regulation or groundwater regulation,” but instead “left general groundwater regulatory authority to the States.”

It also rejected the “direct discharge” standard proposed by Maui County and the EPA, holding that not “all releases of pollutants to groundwater are excluded from the scope of the permitting program.”  The Court explained that if it adopted that standard it would allow the owner of a pipe leading directly into navigable waters to “simply move the pipe back, perhaps only a few yards, so that the pollution must travel through at least some groundwater before reaching the sea.” The Court could “not see how Congress could have intended to create such a large and obvious loophole.” The Court also noted that this interpretation is “difficult to reconcile … with the statute's inclusion of ‘wells’ in the definition of ‘point source,’ for wells most ordinarily would discharge pollutants through groundwater.”

Instead, the Court concluded that the CWA requires a permit where “there is the functional equivalent of direct discharge.” It declined to elaborate a precise test for “functional equivalent,” but left the standard for development “through decisions in individual cases.” It explained, however, that “in most cases” the “time and distance" between the point source and the navigable waters “will be the most important factors.” The Court also gave a non-exhaustive list of other “factors that may prove relevant:”

“The nature of the material through which the pollutant travels,”

“The extent to which the pollutant is diluted or chemically changed as it travels,”

“The amount of pollutant entering the navigable waters relative to the amount of the pollutant that leaves the point source,”

“The manner by or area in which the pollutant enters the navigable waters,” and

“The degree to which the pollution (at that point) has maintained its specific identity.”

Justice Breyer authored the opinion of the Court, joined by Chief Justice Roberts and Justices Ginsburg, Sotomayor, Kagan, and Kavanaugh. Justice Kavanaugh filed a concurring opinion. Justice Thomas filed a dissent, joined by Justice Gorsuch; and Justice Alito filed a separate dissent.

Without providing a definition or any guidance on its new standard, the decision is likely to create considerable uncertainty for both regulators and the regulated community for the foreseeable future. It also proves support for the conclusion that legislating is best done by elected legislators rather than courts. As an example, there are millions of people that are responsible for discharges to groundwater, including the owners of every septic system in the United States. They have little guidance from this decision on whether their particular discharge is the “functional equivalent of a direct discharge,” requiring issuance of a permit.

In his concurring opinion, Justice Kavanaugh stressed his view that the decision is consistent with Justice Scalia’s plurality opinion in Rapanos v. United State, 547 U.S. 715 (2006), which was a wetlands enforcement decision. That decision, however, created years of uncertainty in the regulatory and litigation arenas. Justice Kavanaugh’s statement seems to foreshadow more rule making and litigation as a result of this decision.

As for discharges to groundwaters, California already regulates those discharges under state law and requires permits (Waste Discharge Requirements or WDRs).  The conditions of those WDRs are based upon on groundwater rather than surface water quality standards as is the case with NPDES permits. This decision now subjects functional equivalent discharges to groundwater to NPDES enforcement as well. This will be a problem for public agencies attempting to determine the permitting requirements for a variety of current practices, including the use of spreading grounds, percolation basins, or infiltration basins for treating stormwater and other types of pollution.

This AALRR publication is intended for informational purposes only and should not be relied upon in reaching a conclusion in a particular area of law. Applicability of the legal principles discussed may differ substantially in individual situations. Receipt of this or any other AALRR publication does not create an attorney-client relationship. The Firm is not responsible for inadvertent errors that may occur in the publishing process.

© 2020 Atkinson, Andelson, Loya, Ruud & Romo



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