Lawsuit: EPA’s backing of DEQ’s reduced water standards is illegal

Laura Lundquist

(Missoula Current) Two water watchdogs and the Confederated Salish and Kootenai Tribes are taking on the Environmental Protection Agency for allegedly not following the law when it approved some of Montana’s revised water quality standards.

On Monday, three plaintiffs - the Upper Missouri Waterkeeper, the Flathead Lakers and the Confederated Salish and Kootenai Tribes - filed a complaint in Great Falls federal district court, alleging that the EPA violated the Clean Water Act and the Endangered Species Act when it approved Montana’s narrative water quality standard for nutrients, including nitrogen and phosphorus, in October. The EPA’s approval followed more than a decade of industry and municipal opposition to Montana’s numerical standard, which the EPA upheld until October, after the Trump administration took over.

“Clean water is the backbone of the Flathead watershed, it sustains our economy, our communities, and our way of life,” said Coby Gierke, Flathead Lakers executive director. “This is not a resource we can afford to gamble with. Protecting special places like the Flathead requires vigilance, strong science-based standards, and the tools to hold polluters accountable.”

Narrative water quality standards tend to be less protective than numeric standards, which have a specific value above which polluters must curtail their waste, avoiding problems before degradation gets bad enough to be obvious. Narrative standards, on the other hand, require action only after problems are already visible.

In 2011, the EPA issued guidance urging states to adopt numeric criteria for nutrient pollution that was increasingly affecting fish, aquatic invertebrates, wildlife and human health nationwide. By that time, it had become apparent that nutrient pollution from plant fertilizers and human and animal waste was not only impairing the water in states like Ohio and Iowa, but it had also traveled down the Mississippi River to the Gulf of Mexico. There, the excess nitrogen and phosphorus led to algae blooms, aquatic plant growth and excess bacteria, which depleted the oxygen in the water, creating a massive “dead zone” that kills all ocean life across thousands of square miles every summer.

So in 2014, the Montana Department of Environmental Quality adopted numeric standards for nutrients to protect Montana’s lakes and streams, some of which were already suffering. As of 2020, excess nitrogen and phosphorus accounted for nearly one-fifth of all stream miles impaired by water pollution, according to DEQ’s Integrated Report. Unhealthy nitrogen and phosphorus levels, in combination with chronic dewatering and evolving precipitation and land-use changes, are continuing to degrade dozens of waterways across Montana.

But the agriculture and mining industries are opposed to numeric standards. And several of Montana’s cities and towns were concerned that they’d have to build new water treatment plants, even though DEQ included a “variance” rule that exempted most major wastewater discharges from meeting pollution limits for 20 years.

So, opponents have repeatedly turned to the Legislature, which twice passed bills requiring DEQ to eliminate the numerical standards.

In 2021, Senate Bill 358 mandated the elimination of the numeric standard and required DEQ to adopt rules for narrative standards. But the public process to establish narrative standards was never completed, and in May 2022, the EPA denied Montana’s attempt to eliminate the numerical standard, saying no evidence was provided to show that a narrative standard would be sufficient. The EPA added that DEQ’s record from 2020 to 2022 of permitting wastewater discharge “demonstrates that the implementation of the narrative criteria alone does not protect the designated use,” according to court documents.

So the Legislature tried again in 2025 with House Bill 664. This time, the Legislature mandated elimination of the numeric standard but added no requirement for DEQ to develop narrative standard rules.

Even so, the EPA approved the revision on Oct. 3, and DEQ is now issuing discharge permits based upon a single narrative criteria for all bodies of water regardless of local conditions. For example, in October, the DEQ published a draft discharge permit for the East Boulder Stillwater Mine that authorized, based on the narrative standard, the release of 15 pounds of nitrogen effluent a day, a significant increase over the 2023 limit of 0.27 pounds a day, according to court records.

The plaintiffs say the EPA’s approval of the elimination of the numeric standard violates the Clean Water Act, which requires the EPA to approve a new or revised standard based upon the best-available science and evidence that the standard will protect designated uses, such as fish and aquatic life. But the DEQ has yet to submit a formalized narrative standard for approval and has provided no scientific justification, according to the complaint.

“Tellingly, the Action letter ignored EPA's own rules, which instruct that states should only rely on narrative criteria ‘where numerical criteria cannot be established or to supplement numerical criteria,’ the plaintiffs said in their complaint.

Finally, the plaintiffs also assert that the EPA didn’t follow the Endangered Species Act, which requires the EPA to consult with the U.S. Fish and Wildlife Service since reduced water quality could affect threatened bull trout, arctic grayling and other sensitive aquatic species. The EPA hadn’t initiated a formal consultation when it approved DEQ’s elimination of the numerical standard and it apparently has yet to complete such a consultation.

“EPA doesn’t get to rubber-stamp the State of Montana’s illegal water quality rollbacks for polluters and pretend there is no risk,” said Guy Alsentzer, Upper Missouri Waterkeeper executive director. “The law requires agencies to understand how gutting water pollution control standards would impact the state’s clean water resources, including threatened and endangered species, before making a decision. EPA didn’t do their homework before hastily approving the state government’s giveaway to polluters allowing more pollution into our waterways, which will have many deleterious consequences for Montanans.”

Contact reporter Laura Lundquist at lundquist@missoulacurrent.com.