Written by Victoria Whitehead, HPWD General Counsel

On April 23, 2020, the Supreme Court of the United States issued a 6-3 decision in  County of Maui, Hawaii v. Hawaii Wildlife Fund, 590 U.S.,(2020) subjecting groundwater to the Clean Water Act (CWA) under certain circumstances.  Under the CWA, a person is forbidden from discharging pollutants from any “point source” to “navigable waters” without an appropriate permit from the Environmental Protection Agency (EPA). Read the full opinion here.

The question presented in this case is whether a permit is required under the CWA “when pollutants originate from a point source, but are conveyed to navigable waters by a nonpoint source,” such as groundwater in this case.  The Court’s summary further articulated the issue: “suppose, for example, that a sewage treatment plant discharges polluted water into the ground where it mixes with groundwater, which, in turn, flows into a navigable river, or perhaps the ocean. Must the plant’s owner seek an EPA permit before emitting the pollutant?”  The Court held that the statutory provisions of the CWA require a 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.” 

The Court outlined seven factors for consideration when determining whether the discharge through groundwater is a “functional equivalent of a direct discharge. ” While some may be more relevant than others, depending on the facts of the case, those factors include: (1) transit time; (2) distance traveled; (3) the nature of the material through which the pollutant travels; (4) the extent to which the pollutant is diluted or chemically changed as it travels; (5) the amount of pollutant entering the navigable waters relative to the amount of the pollutant that leaves the point source; (6) the manner by or area in which the pollutant enters the navigable waters; and (7) the degree to which the pollution (at that point) has maintained its specific identity. When applying these factors, the Court stated “the context includes the need, reflected in statute, to preserve state regulation of groundwater and other nonpoint sources of pollution.” Check back here for further analysis of the potential impacts of this decision on groundwater use and regulation in Texas.