The United States Supreme Court heard oral arguments on November 6, 2019, in Hawai’i Wildlife Fund v. County of Maui, a groundwater case that challenges the scope of the Clean Water Act (“CWA”).  831 F.3d 754 (9th Cir. 2018).  The Ninth Circuit previously held that where a point source discharge to groundwater is fairly traceable to a navigable water, it falls within the jurisdiction of the Act.

The case requires the Court to decide whether Maui County violated the Clean Water Act by disposing of wastewater through injection wells at its Lahaina Wastewater Reclamation Facility.  In 2012, environmental groups brought suit over the injection wells, arguing the effluent from the injection wells was reaching the ocean and damaging the coral reefs.  Maui County’s position was it did not need a CWA permit because the treated wastewater was not entering the ocean directly, but indirectly through groundwater.

The Court’s primary focus during oral argument was on how the wastewater reached the ocean and what counts as a point source and a nonpoint source.  Justice Roberts, for example, asked at what point is the point source too distant and the impact on navigable waters too attenuated to fall within the CWA. 

Environmentalists’ strategy has been to force the Court to decide whether an alleged polluter like Maui County can evade the CWA by using the groundwater to pollute the ocean.  Justice Breyer called Maui County’s position, which basically advances a “trust the states to regulate under state law” argument, an “absolute roadmap for people wanting to avoid regulation.”    

The Justices are likely looking for a reading of the CWA that does not lead to absurd results. The conservative Justices did not appear to be comfortable with the “fairly traceable” standard used by the Ninth Circuit.