Trace groundwater back to its source and you’ll find an eternal cycle, one where we all play a crucial role.


Imagine you are a droplet of water, carried within a gathering cloud over the wide valleys and rugged mountain ranges of southwest Montana. When the cloud’s mass becomes more than the air can support, you begin careening earthward along with a host of companions.

Some land on trees, rocks, or trickle into ponds only to be blasted by the sun back into the atmosphere. Other droplets run over the surface of the land into mountain streams, which babble and tumble to join the roll of an ever-growing river. You, along with a select group, land on rich black soil and soak into the ground. As you go, some of your friends find themselves sucked into plant roots to be pulled by a chain of water molecules back into the atmosphere. But you continue to sink down, down into the soil.

How much water is in this basin you now occupy? This question comprises a hydrologist’s bread and butter. Wherever the water lands, and wherever it ends up, only a finite amount is available to satisfy the needs of every faction that shares the basin. In “closed basins,” such as the Gallatin River Basin where Bozeman is squarely nestled, more surface water has been legally doled out than actually exists, making the question “How much?” even more important. But when it comes to water, there’s far more than meets the eye. In fact, the majority of the resource lies underground, escaping visible scrutiny.


Beneath our feet — a mile, 150 yards, even five feet down — unseen waters move slowly through the ground. These “aquifers” come in various shapes, sizes, salinities and depths. Out of sight and mind, most of us have only an inkling of how our lives intertwine with these buried reservoirs.

Globally, underground water sources represent 96 percent of freshwater available, excluding glaciers and icecaps, according to the 2017 Montana Climate Assessment, which looked at climate change effects throughout the state.

These subterranean storage units range in size about as much as rivers do, from underground puddles to buried oceans, and some are heavily utilized as traditionally dependable water sources. Insufficient rainfall in the arid West makes agriculture without irrigation unfeasible for certain crops, so aquifers supplement surface water draws or are the primary source sustaining many farms and communities.

In Montana, about half of the state’s population depends on groundwater for domestic water needs, as it’s often the only available water source. In some parts of the West, these groundwater stores have been depleted to the point where scientists and water managers have begun to count down the years until some aquifers have no more to give.

When it comes to using water, a balance must be struck— and must account for groundwater, not just surface water. Ideally, the resource is equitably distributed between agricultural, environmental and industrial/municipal uses: the three-legged stool.

The agricultural portion of the stool affects groundwater in marked and interesting ways, and changing irrigation practices can precipitate changes to the underlying aquifers in places like the Gallatin Valley.

Beyond the reach of written history in the Americas, sagebrush carpeted the Gallatin Valley. As homesteaders settled the area, the sea of soft green gave way to cultivated fields watered by canals that diverted part, or all, of the Gallatin River’s water, to flood the fields so crops would grow.

Along with being labor-intensive, flood irrigation is often seen as inefficient and detrimental to rivers and streams because of the volume of water it requires to fill a ditch and convey the life-giving stuff to a farmer’s fields. Organizations with vested interests in keeping water in rivers for wildlife have collaborated with irrigators to safeguard instream flow, sometimes leasing water rights from agriculturalists or helping them line ditches to prevent leaking, therefore requiring less diversion from rivers.

Most crops only require one to two feet of water to grow, yet flood irrigation douses fields in up to five and a half acre- feet over the course of the growing season, according to John LaFave, a hydrogeologist with the Montana Bureau of Mines and Geology.

“That’s way more than a crop needs to grow,” LaFave said. “So that begs the question: What’s happening to all that water that’s being diverted?”

In many places, it’s raising the water table. LaFave told of a canal located on a bench overlooking the Beaverhead River between Dillon and Twin Bridges that was installed more recently than most ditches in the state. When the canal came online in the ‘60s, monitoring wells saw the water table rise 40 feet. On other monitoring wells in the Bitterroot Basin south of Missoula, irrigation leakage facilitated approximately 10 times the recharge of natural processes when the canals filled in May, and the water table remained elevated through March of the following year.

“It’s an incidental consequence of the use of irrigation water,” LaFave said. “And what it’s done is created aquifers in places where there weren’t aquifers and [it] sustains a lot of aquifers.” He added that the artificially high water table formed by canal leakage has created wetlands and lush riparian areas in the Bitterroot Basin, as well as made way for neighborhoods that rely on the water table.

Although similar data hasn’t been recorded in the Gallatin Valley, with its over 2,000 miles of irrigation canals, the case is likely the same. Ironically, as farmers transition from flood irrigation to more efficient irrigation practices that allow them to divert less from the river to water fields, the unintended consequence could be a lower water table.

When the water table declines it could mean less water in the rivers, especially in late summer.

Although center pivots are one of the most efficient ways to water fields, reducing the amount of water agriculturalists must divert from the river, these more efficient irrigation methods may lead to less groundwater recharge and a lower water table, which could in turn mean less water in the river later in the year. Photo by Bay Stephens
Pat Byorth worked 16 years as a fisheries biologist for Montana Fish, Wildlife and Parks, but after constantly bumping into policy that dammed his efforts to protect rivers, he went back to school to become an environmental attorney. He’s spent the last 10 years working with Trout Unlimited in Bozeman. Photo by Bay Stephens


Running out of the house with his brothers as a kid, Pat Byorth would strap a fishing rod or shotgun across the handlebars of his one-speed Stingray bike and ride out of town to shoot pheasants or catch fish. The Byorth boys cowboyed on ranches and backpacked in the summers, hunted in the mountains and prairies surrounding their hometown of Billings, Montana. A love for the mountains, fields and streams of the West grew like Bitterroot flowers out of Byorth’s young days in untamed places.

“We were kind of raised feral,” Byorth said, smiling at fond memories. “We just ran wild, literally, out in the wild.” Strong-built and tall, Byorth has gentle eyes that complement his short brown hair and grey-flecked moustache. His life and work have revolved around the natural world, especially its rivers, which still connect him with Mother Nature on a profound level.

As a former fisheries biologist on the Madison and Gallatin rivers and now an attorney with Trout Unlimited, Byorth, who was also recently appointed to the Fish and Wildlife Commission, has always focused on waterways, but his scope has expanded to encompass groundwater as well.

While it was once thought that groundwater and surface water were distinct from one another, it’s now scientifically understood that they comprise one entity, one body, one resource.

“Rivers are the expression of the water table,” as Byorth put it.

Illustrating this, Byorth says, when a river runs high and full-bore, such as during spring runoff, someone on the bank wouldn’t have to dig far to find groundwater: It will be at the same elevation as the river. On the flip side, in late August when the river is low, one would have to burrow far deeper to reach the substance.

Essential to river health, groundwater is the only reason mountain streams continue running in the late summer heat when the mountain snowmelt is spent. According to Byorth, groundwater stays between 36 and 42 degrees Fahrenheit, keeping coldwater fish like wild trout cool and happily respiring in the oxygen-rich water. The death knell for these aquatic residents is when water temps rise above the dreaded 82.5 F mark. The less water in a river, the higher its susceptibility to temperature fluctuations.

Groundwater also supplies river baseflows when winter has locked everything up in wind-swept snowdrifts. The warmer- than-air groundwater discharging from riverbeds prevents the waterways from freezing completely. For either temperature extreme, coldwater fish rely on groundwater for survival, spending much of their time near segments where it joins the river.

In fly-fishing capitals like Bozeman, healthy fish correlate to a thriving economy, so when access is limited, business feels the pinch. On occasions when rivers hover above 70 degrees for a prolonged period of time, Montana Fish, Wildlife and Parks can implement partial and complete fishing closures on stretches to reduce the stress on fish, which has happened on the Gallatin five of the past 10 years, according to Byorth.

Using an integrated, relational database and mapping program developed by members of World Bank, Byorth demonstrated how a 42-day closure between July 19 and August 29, 2017 resulted in a loss of $984,000 in tourism revenue and $196,000 in income. According to the database, the closure cost the local economy approximately $24,000 per day.

Ecologically, thriving river denizens are also critical to the surrounding terrestrial ecosystem. Take the mountain whitefish, for example.

“They’re just osprey food,” Byorth said, with a wry smile. Able to reproduce themselves by a factor of 120 in a single spawn, whitefish are abundant for predators, in terms of population density, and are also less cover-oriented. They feed back into the greater ecosystem, helping sustain eagles, minks and otters, which in turn fertilize the surrounding forests and grasslands.

Even property values are contingent on river health, Byorth explained: No one wants to live near a sick river. Likewise, rafting, biking and hiking along such a river is not as alluring as when recreators can witness ospreys plucking hearty whitefish from the emerald waters. “A healthy river pays for itself in terms of economics and ecology,” Byorth said.

Gallatin Valley from the air. Photo by Outlaw Partners photo


Bozeman is growing — aggressively. With an estimated growth rate of 3.6 percent between 2016 and 2017, according to a U.S. Census Bureau report released last year, the population is expected to breach 50,000 by 2020 and stands to double in 20 years if the growth keeps up.

More people require more places to live, which means more building and increased demand on water resources. Although the city of Bozeman relies primarily on surface water from Sourdough and Hyalite creeks to provide drinking water, according to the city’s website, homes and subdivisions built beyond the municipal water system must look elsewhere for the resource. For a period, the easiest solution was to punch what are called “exempt” wells.

Intended to give small-scale appropriators a break from the hassle and cost of acquiring a permit when they posed little threat of affecting neighboring water rights, exempt wells aren’t required to obtain a permit from the Department of Natural Resources and Conservation to appropriate water, so long as the well draws remain beneath specific rate and volume thresholds.

Although the wells worked in most areas of Montana, such as where ranchers live miles from the nearest neighbors and draw small volumes to water livestock, things got complicated in counties where growth was off the charts and subdivisions were popping up like spring flowers.

In response to a statutory amendment in 1991 reducing the flow rate allowed under the exception and adding a volume limit, DNRC changed the definition of exempt wells in 1993. This gave latitude for huge developments to be built wherein every house had its own well, each able to draw “35 gallons per minute or less, and … not [exceeding] 10 acre-feet a year,” according to the statute. Regardless of the size of a subdivision, developers could dig wells, apply for, and receive certificates from the DNRC without any review on the impact to other water-rights holders or the environment. The definition change sent ripples throughout certain counties in the state.

In Gallatin County, where Bozeman is located, the county commission processed 498 subdivision applications and recorded 13,321 exempt well certificates of completion between 1990 and 2007, according to an article in the Journal of Contemporary Water Research and Education. Many of these “straws” pulled groundwater destined for the Gallatin River and other tributaries.

Part of the issue with exempt wells in large subdivisions was that they didn’t play by the same rules that large permitted wells or senior rights holders do, though they could potentially draw the same or even a bigger volume of water. It’s difficult to know their exact effect, but exempt wells could suck water from the aquifer with little to no oversight or enforcement, while the Gallatin River runs dry and hot, and while irrigators receive the backlash for it from an angry public.

“Subdivisions aren’t all consumptive, whereas ponds: that water’s sitting there and evaporating 3-5 acre-feet a year.”

Although the DNRC recognized that exempt-well uses were outpacing the legislative intent of the wells, and intended to change it, they were hindered by the legislative committee overseeing water law changes in the state and then sued before the department could modify the definition, according to a DNRC Declaratory Ruling.

“Those definitions were developed for specific reasons of the time,” said DNRC Water Rights Bureau Chief Millie Heffner. “And at the time, really, there weren’t a lot of subdivisions occurring. It was primarily agricultural use.”

In a 2014 district court ruling, the definition was reverted to a 1987 version that allowed 35 gallons per minute or less and up to 10 acre-feet a year per project, not per well. Under the ’87 definition, an entire subdivision, which would be considered one project by DNRC, could now only withdraw the amount an individual well could under the previous definition. This limited developments outside central water utilities to between five and 10 homes, depending on water-use restrictions.

The change dramatically slowed development in the county, focusing subdivision construction to areas with established water and sewer districts, according to developer Kevin Cook of Gene Cook Real Estate in Bozeman. He added that the definition change made building more complicated and expensive for developers, meaning pricier homes for buyers.

“It’s just changed the game,” Cook said. “Is it good, is it bad? I say it is what it is … You’ve got a new set of rules, just go play by the new set of rules.”

Cook admitted that builders haven’t quite figured out how to effectively play by the new rules outside of central water supplies, but added that homes in a subdivision hooking up to central water and sewer systems is better for public water supply and wastewater disposal than having individual wells and septic systems.

“Long-term-wise, central water, central sewer, it’s a good thing,” Cook said. “It’s not a bad thing if you’re going to be at higher densities. That’s the appropriate thing to do.”

In closed basins like the Gallatin, acquiring a permit for water rights requires offsetting the water that is used so the effect on the aquifer is a net zero, which is far from simple.

“I wish the state of Montana legislature would pass some new laws that would clarify and give a better, more user- friendly way to deal with this issue,” Cook said, adding that it makes sense why it hasn’t been addressed yet. “[In] Central Montana, Eastern Montana, there’s less development. So, when a large portion of your state doesn’t have this issue in their backyard, it’s really not a major concern to them.”

Exempt wells may not make a substantial dent in water lost to the watershed, considering 90-95 percent of in-home domestic use returns to the basin — by way of the sink and a water treatment plant. However, water pumped for use on lawns and gardens, and especially to fill private fishing ponds, represents water lost to the system.

“Subdivisions aren’t all consumptive, whereas ponds: That water’s sitting there and evaporating 3-5 [acre-] feet a year,” said Travis Horton, FWP fisheries manager for the region. “The rate that they’re being developed and dug is not sustainable from the water perspective in this valley.”

Also supplied by exempt wells, Horton has seen the size of ponds increase over the years to such a degree that he believes some are exceeding the volume restrictions placed on exempt wells. “There’s no universe to assume that ponds are a benefit to the resource in terms of water,” Horton said. “There’s no way. I put it as bleeding to death by a thousand paper cuts.”


Whiskey’s for drinking and water’s for fighting over, as the adage goes. The essential resource has always been scarce in the American West, and the history of conflicts surrounding it bears testament.

And no more water is on its way, at least according to climate projections. The Montana Climate Assessment predicts warming temperatures will likely reduce snowpack at mid and low elevations, while earlier snowmelt will cause earlier peaks in spring runoff, resulting in decreased late-summer water availability.

“Groundwater demand will likely increase as elevated temperatures and changing seasonal availability of traditional surface-water sources (e.g., dry stock water ponds or inability of canal systems to deliver water in a timely manner) force water users to seek alternatives,” the assessment states.

Comprehensive monitoring may be one way to better understand where water moves and how much there is, allowing for better decision making in the face of reduced water availability.

In 2009, the Idaho Water Resource Board, with support from the Idaho Department of Water Resources, adopted a comprehensive aquifer-management plan for the Eastern Snake Plain Aquifer. The plan involves a sophisticated water-monitoring system designed to show as precisely as possible where every drop of water goes in the basin.

The board predicted an escalation of conflict between water users, increased litigation, increased likelihood of groundwater curtailment, and limited opportunities for community and economic growth, among other foreboding projections, unless an adaptive management plan could strike a balance between water use and supply in the aquifer.

In the Gallatin Valley, a network of 64 wells monitored between the Gallatin Local Water Quality District and the Montana Bureau of Mines and Geology keeps tabs on the groundwater and its quality, but more is better when it comes to monitoring, says GLWQD District Manager Tammy Swinney.

“It’s always good to have more data,” Swinney said. “More information allows you to make better and more well-informed decisions. In my opinion, you could never collect enough groundwater quality or water-level data.”

Although she thinks no organization alone can gather truly robust data, Swinney says partnerships between organizations to share information could work powerfully, ideally revealing shared gaps in data that could then be filled. The information could map out the best ways to mitigate water usage, maintain a high water table and slow the exodus of the resource from the Gallatin Valley, thus helping to alleviate conflicts related to the need for water.

“If we can keep more water in the valley,” Swinney said, “especially in those critical times of the summer when irrigators need it, fish need it, recreationists want it, homeowners want it, then we need to find a way to keep as much of the water that enters our watershed here as long as possible before it leaves.”

At key locations and times of year, Swinney says managed flood irrigation in the Gallatin Valley might help maintain the high water table on which both well owners and the river rely. It could also act as an artificial replacement for a decreasing snowpack that has historically held water late into the summer. The materials we choose to use for our driveways, sidewalks and parking lots can also contribute to aquifer recharge and slowing water down.

“We need to find a way to keep as much of the water that enters our watershed here as long as possible before it leaves.”

“The more we grow, the more impervious surface we’re going to have,” Swinney said. “We’re going to have more roads, more sidewalks, more parking lots, more rooftops, more driveways.”

As rainwater or snowmelt hit these impermeable surfaces, the water sweeps all the sediment, debris and mechanical fluids from cars into storm drains, which send the grimy cocktail straight into the streams lacing through Bozeman. Impervious surfaces facilitate water leaving the valley quicker, polluting waterways in the process.

Officials with the city of Bozeman are working to address this issue, pushing for land-use choices that leverage the filtering power of soil to slow and clean water destined for streams. Using pavers akin to those employed by the Roman Empire to build roads, the city built a patio surrounded by a “water-wise garden” outside City Hall as an example for others to follow.

“We’re really trying to model best practices when it comes to stormwater management,” said the city’s stormwater program coordinator, Kyle Mehrens. Pavers allow water to percolate down into the soil, acting as flood control, water filtration and preventing water that’s laden with fish- and insect-harming pollutants from rushing over concrete to the nearest stream, according to Mehrens.

The city also broke ground on a pilot infiltration garden just south of Langhor Park that catches stormwater and filters it through the garden’s soil before it joins Mathew Bird Creek, allowing clean, soil-filtered water to join the stream as was the case before Bozeman existed.

The effects of these projects and choices may seem small, but they add up when it comes to keeping water in the valley. After all, we have a budget to keep.

Interlocking pavers allow rain and snowmelt to run between the pavers and seep into the soil, a process called infiltration. The method acts as flood control and allows the soil to filter the water and to recharge the shallow aquifer. Photo courtesy of City of Bozeman
Southwest Montana is renowned for its fly fishing, but some anglers may not realize how groundwater keeps the river cold in the heat of late summer and warm enough in the chilled heart of winter for coldwater fish to thrive. Photo by Kene Sperry


When it comes to protecting the marvels of the natural world in the midst of growth and change, Byorth says complacency is the enemy. Many of Montana’s rivers were thrashed in the past 200 years, used for sewage or contaminated by mines. A grinding, multigenerational struggle has returned them to their current legendary status, but there’s more to be done.

“Without the policy changes, or cultural changes that let policy change, the Montana that I grew up in, the Montana that I love so much — the streams, the rivers and fish and the ospreys and eagles and lynx, you name it — won’t be here,” Byorth said. “Won’t be here for my kids and my grandkids.”

Yet water is also necessary to grow the food we eat and to supply drinking water for the homes in which we live.

Water management in Western states is far from simple, especially with its complex history. Stewarding the resource successfully will require approaching the task on a case-by-case basis, so that communities within basins come together to decide how their watersheds should be managed. Partitions between and within communities will have to be dismantled, replaced by citizens rallying over shared goals.

Otherwise, the contradiction of the West will persist. People will come to seek the solitude of a quiet stream and fish beneath vaulting skies, but in doing so will contribute to the demise of their surroundings. In seeking to enjoy the marvels of this Western landscape, we stand to instigate their disappearance.

More than any other resource, water has defined the region’s past and will continue to define its future. Water cannot be an afterthought in the West because here, we’re not getting any more.

Bay Stephens is a staff writer for Mountain Outlaw magazine.