Montana, a state renowned for its breathtaking natural beauty, including pristine high-alpine lakes and abundant trout-filled rivers, is undergoing a significant shift in its approach to water quality protection. Historically, Montana has been at the forefront of environmental stewardship, notably becoming the first state in the nation to implement numeric water-quality standards for dissolved nitrogen and phosphorus in 2014. These nutrients, crucial for aquatic ecosystems in moderation, can lead to severe environmental degradation when present in excess.

Excessive levels of nitrogen and phosphorus, often stemming from industrial activities such as mining, municipal wastewater discharge, and agricultural runoff, can trigger prolific algal blooms. These blooms are not merely an aesthetic nuisance; they critically deplete dissolved oxygen in the water, leading to widespread fish die-offs. Furthermore, dense algal mats can block sunlight from reaching the depths, hindering aquatic plant life, and some algal species can produce potent toxins harmful to human health if ingested through contaminated water sources.

Water quality standards, established by states and tribes and approved by the Environmental Protection Agency (EPA), serve as the cornerstone for ensuring that water bodies are safe for both human consumption and the survival of aquatic life. These standards guide a state’s environmental policy, influencing everything from the remediation of polluted waters to the permitting process for direct dischargers of wastewater, commonly known as point-source polluters. Standards can be defined in two primary ways: numerically, by setting specific maximum allowable concentrations of pollutants before negative impacts are observed, or narratively, by describing the desired condition of clean waterways based on observable degradation parameters.

In a move that has drawn considerable scrutiny from environmental advocates and scientific experts, the Montana Legislature, with the EPA’s endorsement as of October, has moved to repeal the state’s numeric nutrient standards. This legislative action effectively reverts Montana’s water quality framework to its existing narrative standards. Environmental groups and water-quality professionals widely consider narrative standards to be less protective than their numeric counterparts. The critical distinction lies in their timing and enforceability: numeric standards act proactively, compelling polluters to treat their wastewater before ecological damage becomes evident, whereas narrative standards are reactive, coming into play only after pollution-related problems have already manifested. Numeric standards provide clear, quantifiable benchmarks for maximum pollution levels, making them readily enforceable, while narrative standards are more subjective, allowing for greater discretion and flexibility for both regulated entities and environmental agencies.

The implications of this shift to narrative standards have generated considerable uncertainty, according to Scott Bosse, Northern Rockies regional director for the nonprofit American Rivers. The precise methodology by which Montana’s Department of Environmental Quality (DEQ) will implement these new standards remains a subject of speculation. The DEQ contends that narrative standards offer a more efficient and flexible approach to pollution prevention, emphasizing a case-by-case evaluation of each water body. This site-specific strategy aims to tailor anti-pollution measures to the unique hydrological and ecological characteristics of individual waterways.

Andy Ulven, chief of the DEQ’s Water Quality Planning Bureau, explained the department’s approach, stating, "We’re really trying to find the best site-specific controls." Under the revised framework, the DEQ plans to monitor the health of sensitive aquatic indicator species, such as mayflies, assess algal growth levels, and measure dissolved oxygen content to inform water policy decisions. While dissolved nitrogen and phosphorus levels will still be considered, Ulven stressed the need to "look at the bigger picture."

However, critics express deep reservations, arguing that the legislation is inherently vague and overly broad. Nine watchdog organizations have collectively called for a moratorium on new wastewater discharge permits until a more concrete plan for implementing the narrative standards is established. This demand highlights concerns that the current ambiguity could lead to a backlog of permits being issued without adequate safeguards.

This is not the first attempt by Montana to dismantle its numeric nutrient standards; previous efforts in 2020 and 2022 were rejected by the EPA, which cited potential violations of the Clean Water Act. This year’s reversal by the agency, occurring on October 3rd amidst a government shutdown, has been described as an abrupt about-face.

Despite establishing numeric criteria for nutrient pollution in 2014, Montana has historically struggled with effective enforcement. The DEQ frequently extended existing permits rather than requiring upgrades to meet the new standards. Now, numerous permit renewals are pending, including those for major urban centers like Billings and Missoula, as well as towns such as Kalispell and Whitefish, whose waters ultimately flow into the ecologically significant Flathead Lake. The existing infrastructure in many of these municipalities and industrial facilities would require substantial investment to comply with the previous numeric standards.

Guy Alsentzer, executive director of Upper Missouri Waterkeepers, argued that investing in modern wastewater treatment technology is essential for the long-term health of Montana’s waterways and its residents, stating, "Nobody wants to pay for it," but emphasizing that "you don’t mess with your goalposts if you have an implementation problem."

Currently, a substantial portion of Montana’s waterways are already considered impaired due to pollution. Over 35% of the state’s river miles and 22% of its lakes are impacted by pollutants from sewage, industrial discharge, and agricultural fertilizers. Environmental organizations fear that renewing permits under the new, more lenient standards could exacerbate this problem, potentially opening the floodgates to further nutrient contamination.

The case of Sibanye-Stillwater, a platinum and palladium mine situated along the East Boulder River, exemplifies these concerns. The mine’s original 2023 permit stipulated stringent numeric limits on nitrogen pollution, a byproduct of its operations, to be met within a decade. However, a newly drafted permit, still undergoing review, permits a more than fifty-fold increase in the allowable nitrogen discharge. This situation is being closely watched as a critical test case for how rivers will be managed under the new narrative standard regime.

Montana’s decision to relax its water quality protections occurs within a broader national context of increased pressure on environmental regulations. This trend is exemplified by recent proposals to significantly reduce federal protections for wetlands across the country. Critics argue that at a time when federal environmental safeguards are being diminished, states should be strengthening, not weakening, their commitment to protecting vital water resources. Montana’s success in rolling back its stricter pollution standards is likely to embolden other states to pursue similar regulatory rollbacks, capitalizing on a perceived shift towards a more lenient EPA.

As environmental protections are systematically dismantled at the federal level, states are facing increased pressure to uphold their own environmental integrity. The precedent set by Montana could signal a broader trend, encouraging other states to re-evaluate and potentially weaken their Clean Water Act protections. "One of the take-home messages here is that the states will see EPA as receptive to these rollbacks of Clean Water Act protections," observed Andrew Hawley, a staff attorney at the Western Environmental Law Center.

In the interim, Montana’s invaluable aquatic ecosystems face escalating vulnerability. "It’s so mind-boggling to me that both the state and the EPA would want to put Montana’s clean water at risk by shifting to narrative standards," remarked Scott Bosse of American Rivers. "We’re basically slitting our own throat." The long-term consequences of this regulatory shift for Montana’s environment, economy, and public health remain a significant concern for many.