Supreme Court Rules that Discharges to Groundwater May Require Permit Under the Clean Water Act

Yesterday, the Supreme Court held that discharges to Waters of the US (wetlands regulated by the federal government) via groundwater are covered under the Clean Water Act "when there is a functional equivalent of a direct discharge." (COUNTY OF MAUI, HAWAII v. HAWAII WILDLIFE FUND ET AL.) The Court concluded that "an addition [of pollutants] falls within the statutory requirement that it be 'from any point source' when a point source directly deposits pollutants into navigable waters, or when the discharge reaches the same result through roughly similar means." This may be a critical issue for people who deal with wastewater, as in whether or not federal regulations can be applied to groundwater carrying pollution from a point source. This nuance of wetland regulation has been a particular issue regarding whether groundwater should be protected by the CWA for years. As the kids would say "tl; dr" - whether groundwater should be treated as connected to traditionally navigable waters, which are regulated under the CWA.

This ruling confirms what has generally been the law for years and avoids creating a giant loophole in the CWA that would have encouraged dischargers to pump into the ground to avoid a need for an NPDES permit. Importantly, the decision rejects the EPA's recent interpretation of the CWA, which would have declined to assert jurisdiction over any discharge that first touches groundwater.

(A little case background: The case came about because Maui County has, for years, pumped treated municipal wastewater into injection wells that carry it deep underground — or so everyone said. In 2011, the EPA funded a tracer dye study that found wastewater from the wells flowing into groundwater and back into the ocean near Kahekili Beach where it was linked to algae blooms that smother coral reefs and cause other environmental damage.) Additional background can be found on the case's Wikipedia page, here: https://en.wikipedia.org/wiki/County_of_Maui_v._Hawaii_Wildlife_Fund

The decision will require some discussion to determine the extent of the "functional equivalent" test, however there is some legal precedent on this to start with. If you have questions regarding the applicability of this decision to your company or project, please do reach out.