On Wednesday, the nine justices of the nation's highest court will hear oral arguments in a case accusing Maui County of violating the federal Clean Water Act.
Maui Mayor Michael Victorino plans to be in Washington, D.C., to hear the arguments, calling the case of "historic importance regarding home rule for Maui County."
The case centers on the use of underground injection wells to dispose of treated wastewater, which was eventually found to be reaching the ocean and damaging sensitive coral reefs.
Plaintiffs argue that is a violation of the 1972 Clean Water Act, the federal law regulating the discharge of pollutants into surface waters like oceans, lakes, and rivers. The law specifically only covers discharge into so-called “navigable waters” rather than groundwater pollution.
That exemption for groundwater has allowed Maui County to pump its treated wastewater underground for decades without running afoul of the Clean Water Act. Several county facilities use injection wells to dispose of effluent, rather than a more costly and regulatory-burdensome ocean outfall system.
Lahaina Wastewater Reclamation Facility, which opened in West Maui in 1976 and currently has four active injection wells, became the subject of scrutiny after a 2006 state Department of Land and Natural Resource report documented substantial coral reef death in the waters off West Maui.
A group of local conservation groups, led by the Hawaii Wildlife Fund, began organizing community meetings and contacting the federal Environmental Protection Agency. Eventually, the EPA commissioned a study to find out if there was a physical link between the injection wells and the ocean.
Craig Glenn, a marine geologist with the University of Hawaii at Manoa, designed and led the study. Investigators used aerial thermal photography and a biodegradable tracer dye to track where injection well effluent was ending up. Glenn said the result of the study was “undebatable evidence” that the wastewater was reaching the ocean.
The wastewater is vastly different from ocean water in terms of temperature, salinity, and nutrient level. When the biodegradable dye appeared in offshore waters, it meant that wastewater was a likely culprit in the reef decline.
The Hawaii Wildlife Fund was joined by several other environmental groups in a lawsuit against Maui County alleging that since the discharge was reaching the ocean, the county was violating the Clean Water Act.
The group won in federal court, and again on appeal. But in Kentucky, a different federal appeals court reached a different decision in another case, what’s called a “circuit split.”
David Henkin, an attorney with Earthjustice representing the plaintiffs in the Maui case, said that only the U.S. Supreme Court can resolve the impasse.
The high court’s interpretation of the law will determine how the Clean Water Act can be applied across the entire United States, potentially resulting in either a significant expansion or restriction on how the 47-year-old law can be applied.