The 2025 Legislative Session unfortunately led to the enactment of several “dirty water bills.” These new laws have undermined Montana’s science-based water quality standards and are now failing to adequately protect our waterways, fisheries, recreational opportunities, and valued public trust resources.
Upper Missouri Waterkeeper is committed to correcting the issues that arose from the last session, reverse course, and ensure our waterways have the protections they deserve. In June 2025, Waterkeeper petitioned the U.S. Environmental Protection Agency (EPA) to recognize that Montana’s recently enacted legislation fails to meet the requirements of the Clean Water Act (CWA) and to deny such changes to the state’s water quality standards.
Below is a summary of some of the most egregious water bills that passed in 2025, why they are a raw deal for waterway health, where they stand today, and what we’re doing to ensure science-based waterway protections remain in place.
HB 664: Repeal Science-Based Numeric Nutrient Criteria – In Court
- Despite the EPA shutting down the same efforts to repeal numeric nutrient criteria in 2021, the Legislature passed and Governor Gianforte signed HB 664 into law in spring 2025, and in the fall the EPA approved the rollback.
- Numeric nutrient criteria are water quality standards designed to protect our waterways from nitrogen and phosphorus. Without them, we have no goalposts for nutrient levels in our water, leading to water quality issues such as algal blooms that degrade recreation and drinking water.
- The State of Montana is now issuing discharge permits without the numeric limits necessary to prevent harm, externalizing costs onto the environment, wildlife, communities, and everyone else’s pocketbooks.
- Example: The renewal permit for the East Boulder Stillwater mine proposed a nearly 6000% increase in pollution discharged from the mine.
- Because of this, a thousand Montana citizens petitioned DEQ to pause all pollution permitting until there is a transparent mechanism for protecting and restoring waterway health in Montana.
- Now: Waterkeeper filed a lawsuit against the EPA for approving Montana’s clean water quality rollbacks that repealed scientific numeric nutrient water quality standards for arbitrary, reactive narrative standards.
HB 685: Repeal Nondegradation Analysis – In Rulemaking
- This bill replaced Montana’s “Nondegradation Analysis” with a “Feasibility Allowance,” allowing DEQ to determine new “feasibility” parameters that would permit lower water quality standards and abandon the existing requirement that DEQ demonstrate why a new polluting activity outweighs the benefits of clean water and healthy rivers.
- This polluter-giveaway bill undermines the CWA by backsliding on protections intended to prevent degradation to our waters.
- A feasibility allowance prioritizes economic development over environmental protection, and will quickly lead to a decline in local water quality.
- Waterkeeper petitioned the EPA to determine that these revisions to Montana’s nondegradation policy violate EPA’s antidegradation policy rules, is inconsistent with the CWA, and to disapprove of its use. When the EPA approved the repeal of numeric nutrient standards under HB 664, the agency didn’t act on HB 685.
- Now: Montana DEQ is now proposing implementing rules for HB 685. Waterkeeper will be submitting formal comments highlighting the rule’s deficiencies, identifying violations of the federal CWA, and explaining why it falls short of protecting Montana’s waterways.
HB 736: Allowing Nutrient Pollution Offsets – In Limbo
- This bill introduces “offsets” criteria for wastewater effluent limits, allowing unscientific, open-ended nutrient credit trading.
- This allows a credit to be generated for a polluting activity when a reduction of pollution occurs at another place in a watershed. This concept lacks any scientific measurement of how credits are generated, offers no assurance that the existing uses of water or downstream users will be protected, creates “sacrifice zones” that are likely to experience hot spots of pollution, and conflicts with existing state and federal water quality protections laws.
- Similar to HB 685, Waterkeeper petitioned the EPA to determine that these revisions to Montana’s nutrient credit trading policy are inconsistent with the CWA and to disapprove of their use. When the EPA approved the repeal of numeric nutrient standards under HB 664, the agency didn’t act on HB 736.
- Now: DEQ has not yet proposed rulemaking on nutrient pollution offsets established under HB 736. Waterkeeper will continue to track the implementation of this bill.