The National Sea Grant Law Center


  • Hawai’i District Court Applies Functional Equivalent Test to Clarify the Scope of the Clean Water Act

  • August 13th, 2021 — by Olivia Deans — Category: Clean Water Act

  • Last month, a Hawai’i district court became the first court to issue a decision applying the U.S. Supreme Court’s new functional equivalent test for the scope of the Clean Water Act. The case was between Hawai’i Wildlife Fund, several environmental organizations, and the County of Maui. The County owns a wastewater treatment facility where wastewater is injected into wells. The wastewater then travels from the wells to a groundwater aquifer and then flows into the Pacific Ocean. In 2012, the environmental organizations sued the County and argued the County was illegally discharging wastewater pollutants without a federal Clean Water Act (CWA) permit. A CWA discharge permit can be complex and difficult to obtain, so the extent of regulation under the CWA is important to many people.

    The CWA is a major pollution control law that was enacted “to restore and maintain the chemical, physical, and biological integrity of the Nation’s waters.” The CWA strives to minimize water pollution by prohibiting the discharge of pollutants from a point source into the navigable waters of the United States without a permit. Generally, a point source is a discrete and confined conveyance such as a pipe or channel. However, it can be difficult to accurately track water as it flows through different ecosystems. A pollutant might flow from a point source into groundwater, which is not covered by the CWA, and then into the navigable waters which are covered. There has been a lot of confusion and controversy about whether a pollutant must be directly discharged into navigable waters for the party discharging it to need a CWA permit.

    Many courts have struggled to uniformly determine when a discharged pollutant is regulated under the CWA. The environmental organizations in this case sued the County of Maui arguing that it was required to obtain a permit for its discharges from the wells into the Pacific Ocean. The County argued that a permit was not required because the wells discharged into groundwater. The district court and the Ninth Circuit both found that a permit was required because the pollutants were “fairly traceable” from the point source to the Pacific Ocean, a navigable water. The County appealed this decision to the U.S. Supreme Court.

    The Supreme Court agreed with the County that the “fairly traceable” test was too broad. Instead, the Court held that a permit is required when there is a direct discharge from a point source into navigable waters or when there is the “functional equivalent” of a direct discharge. The Supreme Court outlined seven factors that may be considered when applying the functional equivalent test, such as the distance traveled, transit time, and amount of pollutant entering the navigable water.

    The Supreme Court directed the Hawaii District Court to re-analyze the case and apply the functional equivalent test to the factual circumstances in Maui. On remand, the district court had to determine whether the wastewater that was injected into wells that ultimately flowed to the Pacific Ocean was a “functional equivalent” of a direct discharge under the CWA. The court analyzed many of the factors outlined by the Supreme Court such as the transit time and distance traveled. The court also analyzed the amount of wastewater and the impact to the ecosystem. After completing its analysis, the district court ultimately concluded that the County must obtain a permit under the Clean Water Act.

    Before the U.S. Supreme Court decision, courts utilized a variety of tests to determine when a permit was needed pursuant to the CWA. Many people hoped the Court’s functional equivalent test would provide clarity for water regulation, and this case was one of the first court opinions to apply it. As a result, this decision will likely provide important direction and guidelines for future water pollution disputes.

  • Olivia Deans
    Ocean and Coastal Law Fellow

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