A federal judge ruled that Maui County violated the Clean Water Act by releasing partially treated wastewater into injection wells close to Lahaina’s coast.

U.S. District Court Judge Susan Oki Mollway ruled on Friday that the county needs a pollutant discharge permit to release the wastewater.

The plaintiffs in the case said the water’s high levels of nitrogen and phosphorous trigger invasive algae outbreaks that are killing coral off Kahekili Beach Park.

Earthjustice filed the lawsuit in 2012 on behalf of the Hawaii Wildlife Fund, the Sierra Club and other organizations. Eathjustice attorney David Henkin said Monday the court will determine penalties after a hearing scheduled for next March.

Maui County spokesman Rod Antone said the county respects the court’s decision but is still reviewing the ruling and evaluating its options.