NPDES Permitting Required for Indirect Discharge, Rules 9th Circuit

The EPA recently published a request for public comment on whether pollutant discharges into groundwater that has a hydrologic connection to waters of the United States (WOTUS) are subject to Clean Water Act (CWA) regulation (February 20, 2018, FR). The CWA contains no cut-and-dried language that clarifies this issue, an absence that over the years has grown to be significant and one the federal courts have needed to rule on in multiple cases. The latest variation was addressed by a panel of the U.S. Court of Appeals for the 9th Circuit in a case involving wastewater disposed into four wells at a treatment facility in Maui, Hawaii.

Ocean sunset

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The wastewater was found to travel underground before entering the Pacific Ocean. The county argued that the disposal could not be subject to National Pollutant Discharge Elimination System (NPDES) permitting under CWA Section 1342 because the wells did not directly discharge into the Pacific, a navigable water and, therefore, a water of the United States. But the panel found that the legal consideration was not whether the discharge reached the ocean directly or indirectly but whether the wells are point sources and whether discharges from those point sources resulted in the addition of a pollutant of a navigable water. The panel found that that was what occurred and ruled against the county.

Polluting the Pacific

The case concerns the Lahaina Wastewater Reclamation Facility (LWRF). The facility receives about 4 million gallons (gal) of sewage a day. While some of this is treated and sold for irrigation, the majority—over 3 million gal a day—is treated and injected into the wells for disposal. Neither the county nor the environmental groups that sued it dispute that some of this wastewater travels underground and enters the ocean. This scenario was confirmed in 2013 by a tracer dye study conducted by the U.S. EPA and the Hawaii Department of Health (HDOH). The study found that about 1 out of every 7 gal of groundwater entering the ocean near the LWRF comprised effluent from the wells.

Point and Nonpoint

Under the CWA, no point source may discharge pollutants into a navigable water unless such discharge is allowed in a NPDES permit. The CWA defines a point source as “any discernible, confined and discrete conveyance.” The Act does not regulate nonpoint source pollution. In its defense, the county argued that the effluent that originated at the wells entered the Pacific through groundwater—a nonpoint source.

In addition, the county contended that under the CWA, it is not sufficient to focus exclusively on the original pollutant source to determine whether a NPDES permit is needed and that how pollutants travel from the original point source to navigable waters matters as well. More specifically, the county asserted that the point source itself must convey the pollutants directly into the navigable water under the CWA. Since the wells discharge into groundwater and then indirectly into the Pacific Ocean, the county said these discharges do not come within the ambit of the statute.

District Court Rules

Four environmental groups sued the county in a U.S. district court, which found for the plaintiffs. The district court based its decision on three independent grounds:

  • The county indirectly discharged a pollutant into the ocean through a groundwater conduit.
  • The groundwater is a point source under the CWA.
  • The groundwater is a CWA navigable water.

On appeal, the 9th Circuit affirmed the district court’s ruling, although for three different reasons:

  • The county discharged pollutants from a point source.
  • The pollutants are fairly traceable from the point source to a navigable water such that the discharge is the functional equivalent of a discharge into the navigable water.
  • The pollutant levels reaching navigable water are more than de minimis.


As noted above, there are many cases that discuss CWA liability when pollutants enter waters of the United States from a point source, and the panel notes several of these to buttress its opinion.

  • Rapanos v. United States (U.S. Supreme Court, 2006). Justice Antonin Scalia recognized that the CWA does not forbid the addition of any pollutant directly to navigable waters from any point source but, rather, the addition of any pollutant to navigable waters; that is, the addition could also be indirect. He further recognized that since the CWA was enacted, lower courts have held that the discharge into intermittent channels of any pollutant that naturally washes downstream likely violates the CWA even if the pollutants discharged from a point source do not emit directly into covered waters but pass through conveyances in between.
    “Although the Court in Rapanos splintered on other issues, no Justice disagreed with the plurality opinion that the CWA holds liable those who discharge a pollutant from a defined point source to the ocean,” the 9th Circuit panel noted.
  • Concerned Area Residents for Environment v. Southview Farm (1994), the 2nd Circuit held that the collection of liquid manure into tankers and their discharge on fields from which the manure directly flows into navigable waters are point source discharges. Regardless of whether the field itself was a point source, the court concluded there was a point source discharge under the CWA because the pollutant itself was released from the tanker, a point source, and there was a direct connection between the field and the navigable water.
  • Sierra Club v. Abston Construction (1980). The 5th Circuit recognized that the ultimate question as to CWA liability is whether pollutants are discharged from discernible, confined, and discrete conveyances either by gravitational or nongravitational means. It held that basins dug by miners and designed to collect sediment are point sources even though the materials are carried away from the basins by gravity flow of rainwater. Gravity flow, resulting in a discharge into a navigable body of water, may be part of a point source discharge if the miner at least initially collected or channeled the water and other materials, said the 5th Circuit. “That is what occurred here,” commented the 9th Circuit panel.

The panel also rejected arguments by the county that only states and not the EPA have the authority to regulate well disposals and that the county was not given fair notice by the HDOH that NPDES permitting was required for the wells. The requirement to have a permit exists in the CWA, replied the panel, and that is sufficient to warn a party about what is expected of it.

The panel’s opinion in Hawai’i Wildlife Fund v. County of Maui is here.


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