In a ruling July 15, U.S. District Judge Susan Oki Mollway ordered Maui County to obtain a permit under the Clean Water Act (CWA) consistent with the analysis established by the Supreme Court’s April 2020 ruling that injection wells could fall under the CWA. The District Court decision marks a first-time application of the Supreme Court’s landmark test on when pollutants that travel through the groundwater require a permit. The Court reasoned that the discharge from the county’s injection wells into the groundwater, and ultimately into the ocean, is the functional equivalent of a direct discharge such that it triggers the National Pollutant Discharge Elimination System (“NPDES”) permit requirement.

In the case, Hawai’i Wildlife Fund, et al. v. County of Maui, the District Court applied the Supreme Court’s test set out in its April ruling which requires an NPDES “permit when there is a direct discharge from a point source into navigable waters or when there is the functional equivalent of a direct discharge.” In the Supreme Court Opinion, Justice Breyer writing for the 6-3 majority, noted that Courts should consider seven factors when determining if a discharge is the functional equivalent of a direct discharge:  transit time, distance traveled, 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 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 noted that further “time and distance will be the most important factors in those cases, but not necessarily in every case.”

Future legal battles over water contamination from pollution sources such as leaking pipelines, feed lot manure lagoons, and coal ash ponds could be impacted by the federal court’s decision.