The U.S. Supreme Court recently agreed to review the scope of the federal Clean Water Act (“CWA”), which prohibits the discharge of pollutants into navigable waters from any point source. The Court will review a case out of the Ninth Circuit, County of Maui v. Hawai’i Wildlife Fund et al., No. 18-260, which held that the CWA applied to groundwater originating from a point source when the groundwater flowed into navigable waters.

The CWA provides for both civil and criminal enforcement, as well citizen’s suits. If found liable, depending on the underlying action, defendants can be subject to injunctive relief, civil penalties, criminal fines, and possible imprisonment. The award of attorney’s fees is also possible.

The underlying case involved a citizen suit by the Hawai’i Wildlife Fund and other groups against the County of Maui. The suit claimed that the County’s practice of discharging wastewater from its treatment plant into underground injection wells was a violation of the CWA, as the wastewater from the wells migrated through groundwater and ultimately flowed into the Pacific Ocean. Maui did not have a CWA permit for this activity, nor did the County believe a permit was required. While the Pacific Ocean meets the definition of a navigable water, and wells are point sources, Maui believed that the conveyance of the wastewater through groundwater did not constitute a point source discharge subject to the CWA. The district court disagreed, granting summary judgment for the plaintiffs, and the Ninth Circuit affirmed. Hawai’i Wildlife Fund v. County of Maui, 886 F.3d 737 (9th Cir. 2018). In granting certiorari, the Supreme Court framed the issue as follows:

Whether the CWA requires a permit when pollutants originate from a point source but are conveyed to navigable waters by a nonpoint source, such as groundwater.

If the Court affirms the lower court, the reach of CWA liability would be greatly expanded. Any discharge from a point source would need to be evaluated for CWA permit coverage if the possibility exists for the discharge to eventually reach a navigable water. Failure to do so could result in potential claims comparable to those asserted in the Maui case.

Moreover, as the Fifth Circuit has held, the CWA’s criminal sanctions for negligent discharges require only proof of ordinary, not gross, negligence. See United States v. Pruett, 681 F.3d 232, 241-43 (5th Cir. 2012). It is conceivable, if Maui is affirmed, that negligence in failing to ascertain that a discharge ultimately reaches a navigable water could result in criminal liability.

Briefing on the case is currently scheduled to be completed in July of 2019, and the case could be argued at the Court’s October 2019 sitting. A decision could be issued by early 2020.