Recently, the United States Supreme Court agreed to consider whether liability under the Clean Water Act (“CWA”) extends to pollution traveling through groundwater prior to reaching federally regulated water. The Court’s decision may drastically redefine the scope of the CWA, impacting permitting across the country. The potential implications for regulated parties are significant. According to the Solicitor General’s Office, “[g]iven the potential breadth of those provisions, and the ways in which groundwater may be connected to navigable waters, the question presented here has the potential to affect federal, state, and tribal regulatory efforts in innumerable circumstances nationwide.”
The High Court’s forthcoming interpretation may have sweeping consequences for regulated entities under the National Pollutant Discharge Elimination System (“NPDES”), the CWA’s permitting regime. The CWA prohibits the discharge of “any pollutant to navigable waters from any point source” without a permit. “Navigable waters” has been broadly defined as “waters of the United States”. Traditionally, courts have not extended federal jurisdiction over point source discharges to groundwater, leaving regulatory oversight of groundwater to state or tribal entities. Thus, NPDES permits under the CWA are generally issued to “point source” dischargers of pollutants to waters of the U.S. with a “discernible, confined, and discrete conveyance.”
However, the recent Ninth Circuit decision of Hawai’i Wildlife Fund v. County of Maui, 886 F.3d 737 (9th Cir. 2018), held that dischargers must obtain a permit if groundwater acts as an indirect conduit for the migration of pollutants to navigable waters. Consequently, the Ninth Circuit concluded that Maui County violated the CWA by allowing pollutants from four wastewater injection wells to reach the Pacific Ocean via groundwater. The appeals court reasoned that the County discharged pollutants from a point source (the injection wells) that was “fairly traceable” to a navigable waters (the Pacific). Thus, the County was subject to the CWA’s permitting requirements even though they did not directly discharge the pollutants into the ocean. Maui County asked the Supreme Court to review the Ninth Circuit’s finding that the CWA grants permitting authority to the federal government or its delegates where the pollutants are “fairly traceable” from the point source to a navigable water.
