Environmental agency denies petition to designate Big Hole River as impaired by nutrient pollution

Associated Press

25-04-2025

Montana's environmental regulator has denied a petition to designate the Big Hole River as impaired by nitrogen and phosphorus, throwing a wrench in environmentalists' efforts to put the blue-ribbon fishery on a 'pollution diet.'
Upper Missouri Waterkeeper and the Big Hole River Foundation contend that excess nutrients are creating regular summertime algal blooms that can stretch for more than a mile, robbing fish and the macroinvertebrate bugs they eat of the oxygen they need to thrive. The groups argue in the petition they sent to the Montana Department of Environmental Quality last month that an impairment designation would direct the agency to identify and work to reduce the river's pollution sources in an effort to rebalance the river's aquatic ecosystem.
Common sources of nutrient pollution include runoff containing fertilizers, insecticides and herbicides as well as poorly maintained septic systems and livestock manure.
On April 14, about a month after receiving the 32-page petition, DEQ wrote that it 'cannot grant' the group's petition. The agency's letter doesn't quibble with the groups' findings, which were detailed in a five-year data collection effort. Instead, the agency suggested that legislation passed in 2021 has tied its hands.
'As a result of Senate Bill 358, passed during the 2021 Legislative Session … DEQ is unable to base nutrient assessment upon the numeric nutrient criteria,' the letter, signed by DEQ Director Sonja Nowakowski, reads.
In an April 23 conversation with Montana Free Press, Upper Missouri Waterkeeper Executive Director Guy Alsentzer criticized the agency's decision, arguing that it did not use the best available science and applied 'illogical and disingenuous' reasoning in its denial.
'EPA already took action and struck down Senate Bill 358 from the 2021 session,' Alsentzer said, referencing federal regulators' oversight of state laws and rules governing water quality. 'Numeric criteria are applicable.'
A spokesperson for the EPA confirmed Alsentzer's assertion, writing in an April 24 email to MTFP that numeric nutrient standards for nitrogen and phosphorus the agency approved a decade ago 'remain in effect for Clean Water Act purposes' and will remain so 'unless or until the EPA approves the removal of the currently applicable numeric nutrient criteria and approves revised water quality standards.'
A DEQ spokesperson did not directly answer MTFP's questions about what water quality standards DEQ is using to assess Montana waterways and determine whether permittees are complying with state and federal regulations.
The agency wrote in an email that no permitted pollution sources under its regulatory oversight are discharging into the Big Hole, suggesting that its enforcement role is limited. The agency also wrote that an impairment designation is not required to implement water quality improvement projects such as creating riparian buffers, improving forest roads, or creating shaded areas.
'Watershed partners may begin actively working on nonpoint source pollution reduction projects at any time,' DEQ spokesperson Madison McGeffers wrote to MTFP. 'There is nothing standing in the way of starting work on these types of projects to improve water quality. In fact, the Big Hole River Watershed Committee is actively implementing its Watershed Restoration Plan with funds and support from DEQ Nonpoint Source & Wetland Section's 319 program.'
Alsentzer countered that a science-based cleanup plan and greater accountability will benefit the Big Hole regardless of whether nutrients are flowing into the river from a pipe or entering via more diffuse and harder-to-regulate channels.
'You can't get to that if you don't recognize that you've got a problem we need to solve,' he said, adding that an impairment designation 'unlocks pass-through funding to the tune of millions of dollars.'
Addressing manmade threats to the Big Hole should be a priority for DEQ, given local communities' economic reliance on a healthy river, he added.
'It's just a real tragic state of affairs when you have a blue-ribbon trout fishery in a very rural county that's essentially having its livelihood flushed down the drain because we can't get our agencies to actually implement baseline river protections (and) use science-based standards,' Alsentzer said. 'When people try to do the work for the agency and help them, they're getting told to go pound sand. I think that's wrong.'
Two years ago, Montana Fish, Wildlife and Parks biologists recorded historically low numbers of brown trout along some stretches of the Big Hole. Anglers and conservationists floated a number of possible contributing factors, ranging from pathogens and drought conditions to angling pressure and unmitigated pollution. Save Wild Trout, a nonprofit formed in 2023 to understand which factors merit further investigation, described the 2023 southwestern Montana fishery 'collapse' as a 'canary in the coal mine moment.'
In response to the 2023 population slump, Gov. Greg Gianforte announced the launch of a multiyear research effort on Jefferson Basin rivers that FWP is coordinating with Montana State University.
Narrative Standards For 'Undesirable Aquatic Life'
DEQ's letter to Upper Missouri Waterkeeper and the Big Hole River Foundation leaves open the possibility of a future impairment designation based on narrative water quality standards. After mentioning the 2021 legislation, Nowakowski wrote that the agency reviewed the submitted data 'along with other readily available data, in consideration of the state's established narrative criteria.'
The letter goes on to outline the additional material petitioners would need to submit for the agency to evaluate an impairment designation using narrative criteria, which establish that surface waters must be 'free from substances' that 'create conditions which produce undesirable aquatic life.'
In an April 22 letter, Upper Missouri Waterkeeper and the Big Hole River Foundation addressed the petition denial in two parts. First, the groups argued that numeric nutrient standards apply. Second, they resubmitted material — photos, emails, a macroinvertebrate report, and 'Aquatic Plant Visual Assessment Forms' — to support an impairment designation under the looser narrative standards.
'We encourage DEQ to do the right thing, use all available science to determine the Big Hole River impaired for nutrients, and commit to working with petitioners and other (stakeholders) in addressing the pollution sources undermining this world-class waterway and harming the diverse uses it supports,' the letter says.
Alsentzer noted that he has set up a meeting with the EPA to discuss DEQ's treatment of the petition and its description of applicable water quality standards.
The dispute over numeric nutrient standards comes shortly after the Legislature passed another bill seeking to repeal them. Any day now, Gianforte is expected to sign House Bill 664, which bears a striking similarity to 2021's Senate Bill 358. HB 664 has garnered support from Nowakowski, who described it as a 'time travel' bill that will return the state to 'individual, site-by-site' regulations in lieu of more broadly applicable numeric standards.
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This story was originally published by Montana Free Press and distributed through a partnership with The Associated Press.