Groundwater Law Update: Who Needs a Permit to Discharge Water?

May 13, 2020

The United States Supreme Court recently decided a case that will have significant impacts on who might need a permit to discharge water under the Clean Water Act. The case, County of Maui v. Hawaii Wildlife Fund,[1] decided whether a Clean Water Act discharge permit is required when discharge “‘pollutants originate from a point source but are conveyed to navigable waters by a nonpoint source,’ here, ‘groundwater.’” [2] The distinction between whether a discharge is from a point source or nonpoint source is critical to regulation under the federal Clean Water Act (CWA), as the CWA prohibits the addition of any pollutant from a point source to navigable waters without a permit.[3] Nonpoint source regulation of discharges has typically been left to the states, if regulated at all. For dischargers, this distinction has meant the difference between being subject to the significant regulatory power of the Clean Water Act, versus no regulation at all.

The Maui case involves whether Maui County is required to obtain an NPDES[4] Clean Water Act discharge permit for discharging its partially treated wastewater into groundwater wells. The County injects about 4 million gallons of this wastewater into deep wells about a half-mile from the Pacific Ocean.[5] As a result of an Environmental Protection Agency (EPA) study, there was no question by the Court whether the injected pollutants were actually reaching the Pacific Ocean (i.e., a “navigable water”). The EPA tracer dye study indicated that dye (signifying groundwater pollutants) traveling through the groundwater was reaching the Pacific coast.[6] Environmental Groups then brought suit under the CWA to require the County to obtain a discharge permit, though the County had been following this groundwater discharge practice without a permit since the wastewater treatment facility had opened in the 1970s.

The federal district court relied upon the EPA study to grant summary judgment in favor of the environmental groups, based on the determination that a discharge into the groundwater wells was “functionally one into navigable water.”[7] The United States Court of Appeals for the Ninth Circuit upheld the judgment based upon a slightly different standard, stating that a permit was required when the discharge of “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.”[8] The County, however, had argued that the Clean Water Act only applied if the discharge of pollutants occurred directly into the navigable water, and as such, it should not be required to obtain a permit. The EPA, for its part, had taken alternative positions on the issue over the years, most recently taking a position most in line with the County’s argument.

The decision of the Supreme Court, written by Justice Stephen Breyer with a strong 6-3 majority, took a middle-ground approach in its opinion. The Court held that the Ninth Circuit’s “Fairly Traceable” test was too broad and might include pollutant discharges that reach navigable waters after many years, a connection too remote for the Court to accept. However, the Court found that the County’s (and EPA’s) argument, in theory, might allow a pollutant discharger to pull a pipe back even one foot from the waterway, meaning its discharge was no longer a direct discharge as the pollutants traveled the remaining short distance to the navigable water through the groundwater, was equally impractical.

Therefore, Justice Breyer provided a new standard, which he called the “Functional Equivalent” of a discharge to a navigable water.[9] Justice Breyer provided a seven-factor test to help determine whether the CWA permitting requirements might apply, with the first two items being the more important factors[10]:

  1. Transit time;
  2. Distance traveled;
  3. The nature of the material through which the pollutant travels;
  4. The extent to which the pollutant is diluted or chemically changed as it travels;
  5. The amount of pollutant entering the navigable waters relative to the amount of the pollutant that leaves the point source;
  6. The manner by or area in which the pollutant enters the navigable waters; and
  7. The degree to which the pollution (at that point) has maintained its specific identity.

Justice Breyer acknowledged that this list is not inclusive, and there may even be additional factors based on the specific situational circumstances. Certainly, geologists, hydrogeologists, engineers, the EPA, attorneys, and the district courts will require some time to delineate the extent and degree to which these factors apply.

An unrelated, but similarly important, groundwater case relates to the regulation of high capacity wells in Wisconsin. To provide some general background, a “high capacity well” (HCW), often used in agricultural irrigation, is defined as a well that has a pumping capacity of more than 100,000 gallons per day.[11]  One high capacity well may not have a significant impact on surface water when evaluated on its own, and therefore a pumping limit might be set at a higher level or generally approved. However, if there are multiple HCWs within an area or a watershed, those wells might have a cumulative impact on the quantity and quality of groundwater available for pumping, and can even impact surface water quality and quantity of hydrologically connected lakes and rivers.

In 2016, Attorney General Brad Schimel issued an Opinion addressing whether the DNR can review the cumulative impacts of multiple HCWs in considering whether to issue an HCW permit.  In the Opinion, AG Schimel stated that, “Nowhere in the constitution is there language delegating that duty to the DNR. Rather, the Legislature maintains the duty of trustee and can choose to delegate that duty in whole or in part to an administrative agency, or to maintain control and carry out the duty itself.”[12]  On May 1, 2020,[13] AG Josh Kaul issued a directive withdrawing AG Schimel’s Opinion.

The disagreement between the AGs results from two somewhat contrasting mandates from the Wisconsin Legislature and the Wisconsin Supreme Court. A 2011 Wisconsin Supreme Court decision held that the DNR has the duty to consider the environmental impacts of proposed high capacity wells and their impacts to waters of the state under the Public Trust Doctrine,[14] which is included in the State’s Constitution.[15] However, the Legislature responded by enacting 2011 Wisconsin Act 21, which prohibited administrative agencies (i.e. the DNR) from enforcing a permit condition or standard beyond what is explicitly provided by statute (i.e. cumulative impacts standards).[16] The legal question can be summarized as: does the Public Trust Doctrine require or allow the DNR to take into consideration factors that may not be explicitly directed or allowed by statute?

Attorney General Schimel’s Opinion directed that “the DNR has only the level of public trust duty assigned to it by the Legislature, and no more,”[17] concluding that the Legislature is the trustee under the Public Trust Doctrine, unless it explicitly delegates those powers to an agency such as the DNR. The DNR subsequently issued several high-capacity well approvals that may not have been permitted under the cumulative impacts analysis. In 2017, an environmental group challenged the well approvals, and a state circuit court later vacated all but one of the approvals.[18] The issue may not be settled, though, as the case is pending Wisconsin Supreme Court review.[19]

Now that AG Kaul’s directive has withdrawn AG Schimel’s previous Opinion, the DNR may again be able to consider the cumulative impacts of HCWs in issuing permits. Yet, with the state Supreme Court case still pending, more news on this issue is likely to follow.


[1] County of Maui, Hawaii v. Hawaii Wildlife Fund, et al., Docket No. 18-260, 590 U.S. ___ (April 23, 2020).

[2] Id. at 1

[3] 33 U. S. C. §§1311(a), 1362(12)(A)

[4] National Pollutant Discharge Elimination System (NPDES) Permit, the CWA discharge permitting system.

[5] See County of Maui at p. 3, I. B ¶1.

[6] Hawai‘i Wildlife Fund v. County of Maui, 886 F.3d 737, 742-43 (9th Cir., February 1, 2018).

[7] Hawaii Wildlife Fund v. County of Maui, 24 F. Supp. 3d 980, 998 (D. Haw., 2014).

[8] Hawaii Wildlife Fund 886 F.3d at 749.

[9] See County of Maui at 15, V. para. 1.

[10] See County of Maui at 16, V. para. 4.

[11] Wis. Stat. § 281.34(1)(b)

[12] See OAG-01-16 at ¶ 51.


[14] Lake Beulah Management District v. DNR, 2011 WI 54, ¶¶ 39, 63; 335 Wis. 2d 47 (Wis. 2011).

[15] See Wisconsin Constitution, Article IX, Section 1.

[16] Wis. Stat. § 227.10(2m)

[17] See OAG-01-16 at ¶ 53.

[18] See Clean Wis., Inc. v. DNR, No. 16-CV-2817 (Wis. Cir. Ct. Dane Cty.) (consolidated)

[19] See Clean Wisconsin, Inc. v. DNR, Case No.: 2018AP59, Cert. Granted 4/9/2019.

Sean Frye
Sean Frye