Under the Clean Water Act, a party must obtain a permit before adding any “pollutant,” broadly defined from “any point source” to “navigable waters.” In County of Maui, Hawaii v. Hawaii Wildlife Fund, Maui’s sewage plant was pumping millions of gallons of partially treated sewer water into the ground each day, which eventually wound up in the Pacific Ocean. Environmental groups sued, arguing that Maui was discharging a pollutant into navigable waters without a permit. The Ninth Circuit ruled for the environmentalists, holding that a permit is required when pollutants are fairly traceable from the point source to navigable water.

The Court, in a 6-3 opinion authored by Justice Breyer, sought a middle ground between the Ninth Circuit’s position and Maui’s position that having the waste water travel underground before it got to the navigable waters of the Pacific Ocean cut the link. The Court determined that a permit was required when there is a discharge from a point source directly into navigable waters or when there is the “functional equivalent of a direct discharge.” There could be many factors to consider in weighing that determination, including the amount of time and distance the pollutant travels before entering navigable waters. The case was then remanded for reconsideration.

Justice Kavanaugh filed a concurrence stating his belief that this decision adhered to the plurality opinion in Rapanos v. United States, 547 U.S. 715 (2006), and emphasizing the importance of time and distance to the analysis. Justice Thomas, joined by Justice Gorsuch, dissented, arguing for a bright-line test requiring a permit only when the pollutant is directly discharged into navigable water. Justice Alito also dissented, arguing that the majority’s rule would was confusing and would not provide consistent results.

A link to the opinion is here: https://www.supremecourt.gov/opinions/19pdf/18-260_jifl.pdf