Ninth Circuit Upholds Groundwater Conduit Theory

On February 1, 2018, the Ninth Circuit Court of Appeals upheld the “groundwater conduit theory,” whereby a discharge of pollutants into groundwater that is fairly traceable to a navigable surface water is the functional equivalent of a discharge directly into the navigable water body for the purpose of regulation under the Clean Water Act. This argument has been proffered many times in the past, but prior to this case this theory had, at best, narrow and limited success. The full Ninth Circuit case is available here.

The case involved the County of Maui, Hawaii and its wastewater treatment plant. The plant uses four wells as its primary means of disposing effluent into groundwater and the Pacific Ocean. The County injects three to five million gallons of treated wastewater per day into its wells, and, according to the County’s expert, when the County injects 2.8 million gallons of effluent per day, the amount of effluent that reaches the ocean is 3,456 gallons per meter of coastline per day. The Court stated this is “roughly the equivalent of installing a permanently-running garden hose at every meter along the 800 meters of coastline.”

Discharges of pollutants may be authorized by permit under the Clean Water Act’s National Pollutant Discharge Elimination System (“NPDES”). Jurisdiction under the Clean Water Act requires three things: 1) addition of a pollutant 2) to a navigable water 3) from a point source. This case focuses on the third requirement. Clean Water Act cases hold that a point source is a discernible, confined, and discrete conveyance, which in a lot of cases really means a pipe, ditch, or canal.

Wells do not directly connect to navigable water (in this case, the Pacific Ocean). Instead, the water injected into wells must travel through groundwater to reach the ocean. In 2013, the EPA, Army Corps of Engineers, Hawaii Department of Health, and University of Hawaii conducted what is called a “tracer dye study.” Essentially, they put dye into the wells and then monitored the ocean for the dye. At its conclusion, the study found a hydraulic connection between two of the wells and the ocean.

The Ninth Circuit concluded that point source discharges that travel indirectly through groundwater to a navigable water, is a violation of the Clean Water Act if the discharger does not have a permit. The Court reasoned that “this case is about preventing the County from doing indirectly what it cannot do directly.” Since the County could not build a waste pipe that emptied directly into the ocean without a permit, it could do so indirectly through its wells to avoid the requirements of the Clean Water Act. 

There are currently cases before the Fourth and Sixth Circuits which also implicate the groundwater conduit theory. If the holding by the Ninth Circuit is adopted by other Circuits, it will represent a change for the NPDES permitting program and regulation under the Clean Water Act. On the other hand, if a split develops in the Circuits, it may lead to litigation in the United States Supreme Court.

Stay tuned to Schroeder Law Offices’ Water Law Blog for more water news!

This article was drafted with the assistance of Law Clerk Derek Gauthier, a student at Lewis & Clark Law School.