County of Maui, Hawaii v. Hawaii Wildlife Fund (No. 18-260)


Under the Clean Water Act, is a permit required for a point source that transmits pollutants to navigable waters through an intermediary nonpoint source, such as groundwater?

Oral argument: 
November 6, 2019

This case asks the Supreme Court to determine whether pollution added to navigable waters through a nonpoint source is regulated by the Clean Water Act (“CWA”). A point source is a discernable, confined, and discrete conveyance that includes pipes, ditches, and other clearly discernable means from which pollutants are or can be discharged into navigable waters. County of Maui (“Maui”) contends that pollutants that enter navigable waters through nonpoint sources, like groundwater, are too attenuated to attach liability under the CWA. Maui argues that pollutants that enter navigable waters through nonpoint sources are not added “directly to” navigable water and thus fall outside the scope of 33 U.S.C. § 1362(12)(A), the statute that codifies which pollutant discharges are subject to the CWA’s permit requirements. Hawai’i Wildlife Fund (“HWF”) counters that Maui’s reading is underinclusive and that the CWA’s intended purpose is to regulate pollutants not just added directly to navigable waters, but also those that were simply added to navigable waters. HWF argues that discharges of pollutants to nonpoint sources which then enter navigable waters fall within the meaning of “discharge of a pollutant” under the CWA. The outcome of this case has important implications for the continued viability of the National Pollutant Discharge Elimination System’s permit program, the divide between federal and state control of groundwater regulations, and the fiscal impact that the CWA has on individual landowners.

Questions as Framed for the Court by the Parties 

Whether the Clean Water Act requires a permit when pollutants originate from a point source but are conveyed to navigable waters by a nonpoint source, such as groundwater.


In 1972, Congress passed 33 U.S.C. § 1251, or the Clean Water Act (“CWA” or “Act”), to preserve the “Nation’s waters” by prohibiting the “discharge of any pollutant” unless certain requirements in the Act are met. In particular, the CWA requires a National Pollutant Discharge Elimination System (“NPDES”) permit for any discharge of pollutants. The statute, 33 U.S.C. § 1362(12), defines “discharge of a pollutant” as “any addition of any pollutant to navigable waters from any point source.” A “point source” is defined as “any discernible, confined and discrete conveyance, including but not limited to any pipe, ditch, channel . . . from which pollutants are or may be discharged.” Additionally, the CWA allows states to request NPDES permitting authority, which Hawai’i acquired in 1974, subject to oversight from the Environmental Protection Agency (“EPA”).

Petitioner County of Maui (“Maui”) installed four injection wells between 1979 and 1985 in what would become the Lahaina Wastewater Reclamation Facility (“LWRF”). Today, the LWRF is the principal municipal wastewater treatment plant for West Maui, serving nearly 40,000 people and treating approximately 4 million gallons of sewage per day. After treatment, the sewage is either sold for irrigation uses or injected approximately 200 feet underground into a groundwater aquifer from the four wells. Approximately 3 to 5 million gallons of wastewater are disposed of daily from the wells into the groundwater. Maui underwent environmental reviews in 1973 and 1991, which confirmed the spread of the pollutant from wastewater originating from its wells, through the surrounding groundwater, and eventually into the Pacific Ocean. Maui has never held an NPDES permit for the LWRF.

Relying on a 2007 study showing increased nitrogen levels in algae floating offshore from the LWRF and a 2010 EPA tracer-dye study that established a “hydrogeologic connection” between the wells and the ocean, Respondent Hawai'i Wildlife Fund (“HWF”) sued Maui in the United States District Court for the District of Hawaii in 2012 for violations of the CWA. HWF alleged that the spread of wastewater from the LWRF to the Pacific Ocean altered the chemical balance of the ocean water, thus causing an increase in algae blooms and damage to coral reefs. Therefore, HWF sought to compel Maui to acquire and comply with an NPDES permit, and pay civil penalties for the wastewater discharge.

After its initial motion to dismiss was denied, Maui applied for an NPDES permit in 2012 and again requested that the case be dismissed or suspended until the permit application was approved or denied. HWF then moved for summary judgment, citing the tracer study and Maui’s admitted awareness that its wastewater was entering the ocean indirectly through the groundwater as sufficient evidence that Maui violated the CWA. The District Court held for HWF, ruling that Maui violated the CWA by not obtaining an NPDES permit for the wells because (1) the wastewater was indirectly discharged into the ocean through groundwater, (2) groundwater is a “point source” under the CWA, and (3) groundwater is “navigable water” under the CWA.

Maui appealed the District Court’s decision to the United States Court of Appeals for the Ninth Circuit. The Ninth Circuit upheld the lower court’s ruling reasoning that: (1) the wastewater is discharged from the wells, which are a point source; (2) the pollutants are sufficiently traceable from the wells to the ocean, even if the discharge from the wells to the Pacific Ocean is only indirect; and (3) there is more than a de minimis amount of wastewater entering the ocean.

On August 27, 2018, Maui petitioned the Supreme Court of the United States for a writ of certiorari, which the Court granted on February 19, 2019.



Maui argues that when Congress passed the CWA, the law was intended to regulate pollutants from point sources differently than pollutants from nonpoint sources. In support of its argument, Maui contends that the CWA was meant to change the regulatory focus from water quality standards under the CWA’s predecessor statute, the Federal Water Pollution Control Act, to preventing pollutants from ever entering bodies of water through the regulation of point sources. Additionally, Maui claims that after the passage of the CWA, states were almost entirely responsible for regulating nonpoint sources of pollution for themselves, while the EPA only reviewed state plans.

Maui also argues that Congress reaffirmed the CWA’s division of responsibility between the states and the EPA in a 1977 Senate Report that recognized a “clear and precise distinction between point sources, which would be subject to direct Federal regulation, and nonpoint sources, control of which was specifically reserved to State and local governments.” Additionally, Maui contends that the passage of the Water Quality Act of 1987 (“WQA”) further affirmed the distinction in the treatment of point and nonpoint sources, as the WQA amended the statement of goals in the CWA to recognize the danger of nonpoint pollution but did not extend the permitting program to cover nonpoint sources. Maui asserts that the CWA thus provides a clear dichotomy of regulation based on the path that pollutants take: pollutants from point sources must comply with an NPDES permit, and pollutants from nonpoint sources must comply with state control plans.

HWF counters that the CWA’s structure and history do not support Maui’s dichotomous treatment of point sources and nonpoint sources. Instead, HWF argues that the CWA’s structure dictates the opposite result: that NPDES permitting is required at point sources that foreseeably add pollutants to navigable waters. HWF contends that Maui focuses too much on nonpoint sources, while the actual language of the CWA does not even define a nonpoint source. HWF asserts that this unwarranted attention results in an implied catch-all definition of a nonpoint source as merely anything that a point source is not. Instead, HWF contends that a nonpoint source of pollution is better understood to mean pollution resulting from scattered activities over a large area that are not attributable to a single source. Thus, HWF argues that even commonly recognized types of potential nonpoint sources of pollution, like land runoff or the groundwater at issue at the LWRF, can actually be subject to NPDES permitting as long as the pollution still originates from some foreseeable point source.

Additionally, HWF argues that the Court has previously rejected Maui’s argument in S. Fla. Water Mgmt. Dist. v. Miccosukee Tribe, a case where the Court declined to adopt a similar nonpoint source theory as Maui’s because the CWA “does not . . . exempt nonpoint pollution sources from the NPDES program if they also fall within the ‘point source’ definition.” Furthermore, HWF contends that Maui’s argument would make the CWA’s exemptions from NPDES permitting in 33 U.S.C. § 1342(l)(2)–(3) for certain oil, gas, mining, and silvicultural runoff discharges superfluous. HWF argues that if Maui is correct that all nonpoint sources of pollution are already not subject to NPDES permitting, there would be no need for these exemptions at all because the exempted discharges all act as nonpoint sources of pollution at some stage of their activities, such as their contribution to groundwater runoff.


Maui argues that an NPDES permit is required only if pollutants are being delivered to navigable waters by a point source or a series of point sources, based on the words “from” and “any” in the phrase “from any point source” in § 1362(12). Maui identifies two possible meanings for “from” in the context of a point source: (1) the starting point of the pollutants that contaminate navigable waters, or (2) the means or instrumentality of how the pollutants arrive in navigable waters. Maui argues that “from” in this context must mean the latter because: (1) the CWA defines the term “point source” as a “discernible, confined and discrete conveyance,” and (2) conveyance commonly means carrying or transporting something. Maui contends that understanding “from” as referring to a conveyance or delivery is consistent with common usage and previous judicial interpretation.Thus, Maui argues that the Court should adopt a means-of-delivery test that requires an NPDES permit only if pollutants are delivered by any point source to navigable waters. Further, Maui argues that the Court should adopt the definition of “any” previously used in United States v. Gonzales to interpret that word in the context of § 1362(12) as “one or some kind” of point source “indiscriminately of whatever kind.” Maui asserts that while this meaning of “any” proves that an NPDES permit is required even when there is a chain of connected point sources delivering pollutants to navigable waters, it does not mean that the language of § 1362(12) requires a permit when the chain of point sources connected to navigable waters is broken up by at least one nonpoint source.

Based on the means-of-delivery test, Maui argues that it should not be required to obtain an NPDES permit for the LWRF. Maui asserts that in applying the means-of-delivery test, the presiding court should identify the actual conveyance that adds the pollutant to a body of navigable water, and if that conveyance is not from a point source, no NPDES permit is required. In regard to the LWRF, Maui contends that the groundwater, a nonpoint source, acts as the final conveyance of the wastewater into the Pacific Ocean. Therefore, Maui argues, because the groundwater, and not the wells, actually delivers the wastewater to the ocean, the wastewater does not come “from any point source” under § 1362(12).

HWF argues that Maui’s textual arguments regarding § 1362 are erroneous. First, HWF contends that Maui’s interpretation of “conveyance” as referring to means or transportation is incorrect as applied to § 1362(12) because that provision only states that pollutants must come “from” a point source, not that a point source must “convey” anything. Second, HWF argues that the definition of “from” only requires a pollutant to come “from,” and not necessarily to originate “from,” a point source. HFW asserts that a pollutant can thus still be “from” a point source, even if that point source does not directly convey the pollutant into the body of water. Third, HWF contends that “any” actually means that “any” point source that discharges pollutants that reach navigable waters is subject to the CWA—“any” meaning “one or more indiscriminately.”

Additionally, HWF argues that nothing in the CWA should prevent the statute from applying to foreseeable and traceable indirect discharges of pollutants from point sources to navigable bodies of water. Otherwise, HWF asserts, polluters could simply alter their point sources in some manner so that pollutants flow through an intermediary to avoid the permit requirement. HWF argues that the textual requirements that pollutants come “from” a point source is really just a requirement of factual and proximate causation, meaning that the pollutants must be traceable from the point source to the navigable waters and that the spread must be foreseeable. Further, HWF contends that because the definition of “point source” includes “any . . . well,” and wells function by discharging into groundwater, Congress must have intended to include discharges of pollutants from wells into groundwater that reach navigable water under the permitting requirement.

Finally, HWF argues that the LWRF’s wastewater discharges are prohibited by the plain text of the CWA. HWF asserts that the applicability of the CWA to the LWRF depends on the meaning of “addition,” “to,” and “from” in “any addition of any pollutant to navigable waters from any point source.” HWF argues that the broad meaning of “any” means the CWA applies whenever a polluter (1) makes any kind of addition of a pollutant to navigable waters (2) from any point source. HWF claims that the wastewater discharged from the LWRF that spreads to the ocean clearly is an addition of a kind of pollutant to navigable waters. HWF also contends that because the wells are clearly point sources, and because the common understanding of “from” is best understood to refer to the original source of something, the text of the CWA requires the LWRF to have an NPDES permit because the wells serve as the starting point for the discharge of the wastewater being added to the ocean.



The United States, in support of Maui, argues that by including “fairly traceable” releases and indirect releases of pollutants into NPDES requirements, the Ninth Circuit effectively changed the meaning of the CWA despite legislative history that indicates contrary congressional intent. The United States contends that releases to navigable waters cannot be viewed as “adding” a pollutant if the path between the surface water and the point source is too attenuated because any spatial gap between a point source and the surface water falls outside the CWA’s scope. The Federal Water Quality Coalition (“FWQC”) agrees, arguing, in support of Maui, that the CWA was designed to cover point sources that are “discernable, confined and discrete conveyances” and that the Ninth Circuit’s traceability theory would subject previously exempted sources—like public sewage systems and retention ponds—to a fact-specific inquiry to determine whether these releases fall within the NPDES program. Thus, the FWQC asserts that reading the CWA to include groundwater creates a confusing site-specific inquiry that grants potential permittees little certainty in determining their own liability.

A group of Law Professors (“Law Professors”), in support of HWF, asserts that excusing indirect discharges from the NPDES permit requirements renders the CWA incomplete—undermining the CWA’s purpose to protect the nation’s waters. The Law Professors contend that excluding all indirect pollutant discharges creates a loophole that allows entities to knowingly discharge pollutants into permeable surfaces to avoid obtaining an NPDES permit. Furthermore, former EPA Administrators, in support of HWF, contend that there will be no additional burden on the EPA or the states because the EPA has already been issuing NPDES permits for pollutant discharges through groundwater for years. The former EPA Administrators argue that the EPA has always included direct pollution through groundwater under the NPDES program and a contrary reading would allow pollution to navigable waters to remain unregulated, despite the pollution’s clear connection to a point source.


In support of Maui, the United States argues that construing the phrase “discharge of a pollutant” under Section 1362(12) to include releases to groundwater would greatly expand the EPA’s authority, which upsets the balance between the federal and state governments. The Edison Electric Institute and others (“Institute”), in support of Maui, argue that granting groundwater control to the states was the CWA’s most important feature. The Institute asserts that subjecting discharges to groundwater to federal NPDES regulations undermines the CWA’s regulatory scheme. The Institute explains that Congress intended to grant the states control over groundwater because the states were “better suited” to regulate groundwater pollution. Thus, the Institute asserts that interpreting the CWA to cover indirect releases to navigable waters displaces the states’ role in regulating groundwater.

Upstate Forever and Savannah River Keeper (collectively “Upstate and Savannah”), in support of HWF, assert that including releases to groundwater within the NPDES permit requirements does not lead to regulatory expansions. In fact, Upstate and Savannah maintain that the EPA has had, for nearly thirty years, the authority to regulate releases to groundwater that eventually enter navigable waters—in other words, releases through groundwater. Yet, Upstate and Savannah continue, the EPA’s authority had never gone out of control because liability under the CWA arises only where there is a clear connection between a point source and navigable waters. The former EPA Administrators also argue that the NPDES requirements does not upend the states’ authority because the states themselves implement NPDES programs. Specifically, the former EPA Administrators contend that the states are free to modify and supplement the NPDES program by adding additional protections for groundwater—leaving the states with significant autonomy and with the CWA merely serving as a floor.


In support of Maui, the Pacific Legal Foundation (“PLF”) argues that broadly expanding the CWA to include indirect pollutant discharges imposes difficult and expensive requirements on ordinary landowners. The PLF argues that expanding the CWA’s scope subjects to NPDES permit requirements millions of Americans who use septic tanks, salt to de-ice roads, and fertilizer. The PLF asserts that ordinary landowners are unable to meet this regulatory burden—noting that the average applicant spends over 700 days and $270,000 completing the permit process. Several agricultural business organizations (“Agricultural Organizations”), in support of Maui, agree that subjecting stormwater, irrigation, farm ponds, and other farm activities to NPDES requirements will disrupt agricultural production. The Agricultural Organizations further assert that increasing regulations poses an unworkable administrative burden because of the staggering number of farmers that would be subject to NPDES permit requirements.

In support of HWF, a coalition of Craft Brewers (“Craft Brewers”) argues that the impact to individual landowners is misstated because the vast majority of point sources do not actually transmit traceable amounts of pollutants through groundwater to navigable waters. Furthermore, the Craft Brewers argue that the Ninth Circuit’s ruling does not expand the EPA’s authority because sources—like septic tanks—that cause pollutants to enter navigable waters already violate the CWA and require an NPDES permit. Trout Unlimited, in support of HWF, argues that the impact on agriculture industries is also misstated because the CWA expressly exempts “‘agricultural stormwater discharges’ from the definition of a ‘point source.’” Thus, Trout Unlimited contends that Maui and its supporters incorrectly interpret the Ninth Circuit’s holding to impose new liability on landowners because discharges through groundwater are either already subject to the CWA or are expressly exempted from the CWA.

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