County of Maui v. Hawai`i Wildlife Fund

The Clean Water Act (CWA) regulates pollution added to navigable waters from point sources by requiring National Pollutant Discharge Elimination System (NPDES) permits for discharges. In violation of this requirement, Maui County discharges millions of gallons of treated sewage per day into the Pacific Ocean from injection wells at its Lahaina Wastewater Reclamation Facility. These unpermitted discharges are directly injected into groundwater that is directly connected to the ocean. The Ninth Circuit held that disposing of these pollutants directly into the ocean without an NPDES permit would clearly violate the CWA and that the County could not avoid CWA liability by doing it indirectly, noting that “[t]o hold otherwise would make a mockery of the CWA’s prohibitions.” The County then filed a petition for certiorari, arguing that it does not discharge pollutants into navigable waters through a point source because its wells, though meeting the definition of point sources under the CWA, do not discharge pollutants directly to navigable waters. The Court granted the petition.

In the Supreme Court. Public Citizen served as co-counsel for the nonprofit organizations that sued the County for its violations. Our brief argues that the discharges are covered by the terms of the Act because they add pollutants (sewage effluents) to navigable waters (the Pacific) from point sources (the County’s wells). The Act does not require that covered discharged be direct. That the Act generally does not regulate nonpoint sources or discharges that are only to groundwater does not suggest that it exempts point-source discharges that actually and foreseeably flow to navigable waters through groundwater.

On April 23, 2020, the Supreme Court issued its opinion in the case. The Court rejected the County’s argument that discharges must travel directly from point sources to navigable waters to be covered by the CWA, and also rejected the position urged by the United States as amicus curiae in the case, which would have categorically excluded all discharges that travel through groundwater from the CWA’s permit requirement. The Court held that a discharge from a point source is covered by the CWA if it reaches navigable waters directly or is the “functional equivalent” of a direct discharge. The Court stated that the amount of time it takes pollutants to reach navigable waters from the point source, and the distance it must travel, are important factors in determining whether the discharge is the functional equivalent of a direct discharge, and that other circumstances may be relevant as well. The Court remanded the case to the Ninth Circuit for application of the functional equivalent test, which is narrower than the test applied by the Ninth Circuit.