The complex chemistry of Great Salt Lake shapes every aspect of its ecosystem, from microbial communities to bird populations. As a critical stopover on the Pacific Flyway, the Lake's health has far-reaching impacts beyond its meander line. Understanding and effectively managing salinity levels has become increasingly important as Lake levels continue to fluctuate. Adaptive management tools, like the causeway breach and its berm, play a vital role in this effort, offering flexible responses to changing conditions at Great Salt Lake. As we see how quick and effective these tools are at altering the Lake's chemistry, it is imperative that we learn to use them in ways that protect the health of Great Salt Lake - the entire Lake - in perpetuity.

Historical Context

The story of the causeway in Great Salt Lake dates back to the early 1900s, when the Southern Pacific Railroad constructed the Lucin Cutoff to improve transportation efficiency across Utah. Originally a wooden trestle, the crossing was replaced in the 1950s by a rock-filled causeway, physically splitting Great Salt Lake into two distinct environments. With little freshwater inflow, the North Arm (Gunnison Bay) became hypersaline, supporting unique microbial life that at times colors the water pink. At present Lake levels, the North Arm has reached salinity concentrations that exceed thresholds for the diverse ecosystem that once thrived there. In contrast, the South Arm, fed by the Bear, Weber, and Jordan Rivers, fosters a broader array of species, including Brine Shrimp, Brine Flies, and millions of migratory birds, all of which depend on a balanced salinity range of approximately 120-160 g/L (12-16%). The majority of Great Salt Lake’s functional ecosystem relies on the South Arm and associated wetlands.

Hypersaline waters in the Lake's North Arm. Photo: Doug Tolman

In 1984, a 290-ft breach was built near the western edge of the causeway to improve flows between the North and South Arms. As Lake levels dropped below 4,195 in the 2010’s, water stopped flowing through this breach, and the only water exchange between the two arms was through two small culverts on the east side of the causeway. Structural stability concerns led Union Pacific Railroad (UPRR) to permanently close these culverts in 2012, completely bifurcating the Lake once again. To address the need for hydrological connectivity, the U.S. Army Corps of Engineers (USACE) approved the construction of a second, 180-foot breach in the causeway in 2016. Colloquially known as “the breach”, this structure aimed to re-establish balance between the North and South Arms. After six years of water exchange between the Arms, it was observed that while water flowed from the South Arm into the North, dense brine from the North was cycling back underneath, increasing the salt load in Gilbert Bay. Additional salt was, and still is also entering the South Arm through groundwater, though it is unknown how much. Further, salt that is flushed out of Compass Minerals’ evaporation ponds returns a significant amount of salt from the North Arm back into the South Arm. By the time the Lake reached historically low levels in 2022, this salt load had elevated salinity to over 180 g/L (18%), an ecological “cliff” that could have severe repercussions if not quickly addressed.

An Ecological Cliff

The risks of this ecological cliff are highlighted in an emergency petition we filed in October 2022 requesting that the waters of Gilbert Bay be classified as impaired. Our petition, submitted while salinity levels were in excess of 180 g/L (18%), referenced a letter we received from Dr. Bonnie Baxter, of Great Salt Lake Institute at Westminster University. Dr. Baxter’s letter summarized research emphasizing that sustained high salinity levels would lead to a collapse in the Lake’s ecosystem. Findings by Dr. Baxter and others, including modeling by Dr. Gary Belovsky for the Great Salt Lake Ecosystem Program (GSLEP) demonstrate that salinity levels in excess of 180 g/L (18%) disrupt the foundational algae and cyanobacteria essential for the survival of Brine Shrimp and Brine Flies. These keystone species form the base of the Lake’s food web, supporting millions of migratory birds; disruption in this cycle would inevitably lead to mass die-offs throughout the Great Salt Lake ecosystem. In late 2022, signs of this collapse - including smaller Brine Fly larvae, declining Brine Shrimp populations, and emaciated Eared Grebes - were already observed. These declines likely would have continued without the significant precipitation received in the 2022/2023 water year.

For context, Utah Division of Water Quality (DWQ) recognizes that the waters of Gilbert Bay are “protected for frequent primary and secondary contact recreation, waterfowl, shore birds and other water-oriented wildlife including their necessary food chain.” Utah Admin. Code R317-2-6.5(a). This petition to recategorize Gilbert Bay as impaired came in the light of a request by US Magnesium to extend their canals further into Gilbert Bay, which would have lowered Lake levels and increased salinity even further. The recategorization would have acknowledged the impairment of Gilbert Bay’s beneficial uses, requiring DWQ to take action.

In Spring 2024, DWQ requested public comment on an Integrated Report that again categorized Gilbert Bay as a Category 2 (unimpaired) waterbody. This report was based on a two-year period covering 2022 and 2023; much of this time salinity exceeded the 180 g/L (18%) threshold that the Great Salt Lake Advisory Council recognizes as impairing beneficial uses. Though we appreciate the ongoing work done by DWQ, we disagreed with their decision and submitted a public comment again asking them to recategorize Gilbert Bay as impaired.

House Bill 453, passed in Spring 2024, introduced new salinity management requirements for Great Salt Lake. This law directed the Utah Division of Forestry, Fire, and State Lands (FFSL) to establish an emergency trigger based on best practices as recommended by the Salinity Advisory Council (SAC). Applying to salinity concentrations below 90 g/L or exceeding 150 g/L, this trigger gives FFSL authority to curtail or withdraw mineral leases, require operators to implement non-evaporative extraction methods, and to modify the adaptive management berm in the railroad causeway.

Developing Adaptive Tools to Manage Salinity

To curb the risks posed by increased salinity, the state added a simple rock berm at the bottom of the breach at 4,187’ (ASL) in early 2022 to block the dense brine layer (DBL) from returning to the South Arm, colloquially known as "the berm". Raised to 4,192’ in 2023, ASL the the berm has since naturally eroded into a V-shape, lowering the bottom to approximately 4,189’ by Fall 2024. FFSL is currently searching for a more sustainable, mechanical alternative to the rock berm that can be easily adjusted to meet changing conditions.

Contractors with the Utah Division of Water Resources raising the berm in 2023. Photo: Utah FFSL

Water flowing over the berm in Fall 2024, Lake elevation 4193' ASL. Photo: Doug Tolman

Along with salinity requirements, House Bill 453, signed into law in Spring 2024, mandates that the two arms be managed within two feet of one another, aiming to prevent the six-foot or greater discrepancies observed in the past. This policy change coincided with historically wet winters in 2023 and 2024, which introduced a massive volume of freshwater into the South Arm. As water flowed northward through the breach, much of the South Arm’s salt mass traveled with it, an unanticipated result of the flow equalization process. This caused a significant shift in the Lake’s salinity profile: as of November 2024, the South Arm is now within its ideal salinity range, yet the relationship between water level and salinity concentration has changed. Previously, the South Arm would reach the critical 18% salinity cliff around 4,190’ ASL, but now, due to this northward salt migration, that point has effectively shifted three feet lower to 4,187’.

Updated Salinity Curve presented by the Great Salt Lake Brine Shrimp Cooperative in the October 2024 Salinity Advisory Committee Meeting

The adjusted salinity curve shows just how quick and effective the berm is as an adaptive management tool, but also presents new challenges. With the cliff face of 18% salinity now effectively at 4,187’ ASL, there is a new buffer that provides flexibility against reaching the threshold at lower water levels. However, this shift complicates efforts to return to the designated healthy range (4,198 - 4,205’) as outlined in the Great Salt Lake Commissioner’s Strategic Plan. Should we reach that range without addressing this shifted salinity curve, the South Arm would risk becoming too fresh, even under 8 g/L (8%), which could destabilize the Brine Shrimp, Brine Fly, and microbialite populations that depend on optimal salinity. While this shift may temporarily protect the South Arm ecosystem from hypersalinity, other critical concerns remain. Microbialites, navigation, and dust storm events are all impacted by low Lake levels, continuing to impact the health of the Lake and surrounding communities regardless of salinity levels. 

Looking Forward

FRIENDS acknowledges the berm as an important adaptive management tool and applauds the work of the Salinity Advisory Committee, FFSL, and other partners to ensure the Lake's chemistry is balanced. As we see how quick and effective the berm is at altering salinity, it is imperative that we learn how to use this and future adaptive management tools thoughtfully. The distribution of both salt and water across Great Salt Lake's various arms and bays must be managed with the preservation of the entire Lake in mind. Success will require not only precise salinity management but also proactive efforts to ensure stable freshwater inflows, supported by continued collaboration among agencies, industries, and communities committed to protecting Great Salt Lake.

Confluence: Resource Limitations in the West through the Lens of Art, Science, and the Humanities  

Friday, November 22, 5:30 pm – 7:30 pm 

Jones Recital Hall in Gillmor Hall 

Our friends at Great Salt Lake Institute invite you to join them this Friday, November 22nd for Confluence: Resource Limitations in the West through the Lens of Art, Science, and the Humanities. The program includes a panel discussion of the newly-released book A Watershed Moment: The American West in the Age of Limits, with editors Bob Frodeman and Evelyn Brister, and authors Bonnie K. Baxter, Crystal Carr, and Paul Rogers.  

A musical performance by Maya Violet Anderson will accompany the panelists. After the panel there will be food and drink at a reception in Meldrum Science Center featuring installations by artists Kellie Bornhoft, Dana Kuglin, and Diane Tuft.

Click here to read the full report

Dear FRIENDS,

The Utah Watersheds Council (UWC), has released a draft of their annual report, highlighting several new developments aimed at improving water resource management and collaboration throughout the state. UWC brings together state and local leaders, industry stakeholders, and conservation experts to discuss and address water challenges. This year, the council successfully certified 11 local watershed councils, including five within the broader Great Salt Lake Basin. While the Great Salt Lake Watershed Council remains in development, the Great Salt Lake Advisory Council currently serves this role, with representatives from the five watershed councils within the Great Salt Lake Basin participating in advisory meetings.

Additional updates in the report include the hiring of a full-time coordinator who supports both the state and local councils, facilitating meetings and sharing resources. UWC has also received valuable recommendations from local councils, such as improving wildfire response to protect watersheds and enhancing coordination of research on Utah Lake. These insights underscore UWC’s commitment to fostering sustainable water management across Utah’s diverse watersheds. Click here to read the full report and learn more about UWC’s initiatives and ongoing developments.

Dear FRIENDS, 

On October 24, 2024, the Division of Water Rights held a public meeting to discuss its direction under Utah Code section 73-3-33, (Enacted in HB 453) to “regulate the measurement, appropriation, apportionment, and distribution of water within the Great Salt Lake meander line” through the creation and adoption of a Distribution Management Plan for the Great Salt Lake. For more information about the meeting, including a video of the meeting and copies of the presentation slides, visit here. There is a 60-day comment period that goes until December 23, 2024. Comments can be emailed to waterrights@utah.gov or mailed to:

Utah Division of Water Rights
Attn: GSL Distribution Management Plan
PO Box 146300
Salt Lake City, UT 84114-6300

Dear FRIENDS, 

The Utah Division of Forestry, Fire, and State Lands (FFSL) is in the process of updating the Great Salt Lake Comprehensive Management Plan and Great Salt Lake Mineral Leasing Plan.
During this process, there are several opportunities for public input, including a survey you can take right now. During the coming months, there will be several public meetings and info sessions taking place throughout communities within the Great Salt Lake watershed. We encourage anyone who takes interest in this process to attend these meetings and contribute feedback to the survey. 

Click here to visit the project website, where you can learn more about the update, see upcoming meeting dates, and contribute feedback in the survey. 

The Saline Lakes Ecosystem Integrated Water Availability Assessment (SLE IWAA) is hosting a Fall Webinar series to discuss and share research findings from the past year. The webinars are open to the public, and will include live Q&A sessions to engage with the researchers conducting this important work. The first session, taking place Wednesday, October 9 at 12pm MDT, will be an overview of the project, we encourage all who take interest in water resources in the Great Salt Lake basin and neighboring watersheds to attend.

Registration and details: https://www.usgs.gov/special-topics/saline-lake-ecosystems-integrated-water-availability-assessment/news/saline-lake

Time: 12pm-1pm MDT

10/9/24: Project Overview
10/16/24: Water Quantity
10/23/24: Water Quality
10/30/24: Bird Movements
11/6/24: Terminal Lakes Prey Availability
11/13/24: Remote Sensing

More on Saline Lakes Ecosystem Integrated Water Availability Assessment

The Saline Lakes Ecosystem Integrated Water Availability Assessment is a program conducted by the United States Geological Survey (USGS) to expand our understanding of water availability within the terminal watersheds of the Great Basin. By leveraging partnerships with local agencies and universities, the SLE IWAA informs resource managers about the interplay between saline lake hydrology and ecology with best available data. 

From the Division of Water Resources:

Development of the Great Salt Lake Basin Integrated Plan (GSLBIP) is underway, and we need your input!

As part of the GSLBIP, the Division of Water Resources and its partners are simulating how the water supply system and water demands in the basin, as well as how Great Salt Lake and the surrounding wetlands, could be impacted by climate in the future. This will allow us as a community to test the effectiveness of different strategies under stressed or extreme conditions that have not been seen in recent history.

Researchers at the University of Utah are working with the United States Bureau of Reclamation to summarize results from Global Climate Models (GCMs – which simulate future climates) to apply to our Great Salt Lake Basin. We need input from you on the type and timing of climate changes that most affect your organization to best tailor the model results.

Click the button below to complete our brief survey. The survey will close on September 13, 2024.

Take the survey 

For three decades, FRIENDS has been a staunch advocate for Great Salt Lake's protection, tirelessly working to address emerging threats. We are currently working to protect more than 150,000 acre-feet of inflows by protesting wastewater reuse applications and challenging groundwater appropriations, in line with our commitment to achieve comprehensive watershed-based restoration and protection for the Great Salt Lake ecosystem. 

Wastewater Reuse Permits

As wastewater treatment standards become more stringent and wastewater discharges become cleaner, some municipalities in the Great Salt Lake Basin are applying to reuse their wastewater discharge as a source of secondary water, primarily for irrigation. Because wastewater discharges represent a significant portion of Great Salt Lake's inflows, the 2023 amendments to Utah's Wastewater Reuse Act require municipalities in the Basin to file a water replacement plan along with their reuse application.

Some of these municipalities have taken the position that they have a right to reuse their wastewater discharge without replacing those inflows. This stance directly conflicts with recent legislative efforts to preserve and restore Great Salt Lake.

In response, we are challenging applications that lack a sufficient replacement plan. To date, we have filed protests on reuse applications totaling more than 150,000 acre-feet of water. Click here to read our protest.

These protests demonstrate our alignment with the Utah State Engineer's interpretation of the statute as requiring a water replacement plan for all applications. This interpretation is consistent with ongoing legislative efforts to protect Great Salt Lake and the substantial investments made by the state to address declining water levels.

By insisting on comprehensive water replacement plans, we aim to ensure that wastewater reuse projects do not undermine ongoing conservation efforts and the long-term health of Great Salt Lake. This approach recognizes the delicate balance between meeting municipal water needs and preserving the unique and vital ecosystem of the Lake for future generations. We will continue to advocate for responsible water management practices that safeguard the future of Great Salt Lake and the countless species and industries that depend on its health.

Challenging Groundwater Rights Applications

In November 2022, Utah Governor Spencer Cox issued a proclamation "Suspending New Appropriations of Surplus and Unappropriated Waters in the Great Salt Lake Basin." This proclamation, aimed at protecting the declining water levels of Great Salt Lake, covers both surface and groundwater sources feeding the Lake. However, the interpretation and implementation of this proclamation have become a point of contention, leading us to take action.

The State Engineer has interpreted the proclamation as excluding groundwater inflows to the North Arm (Gunnison Bay), which has resulted in a steady stream of water right applications for new groundwater appropriations pumped from aquifers that feed into the North Arm. We argue that this interpretation is inconsistent with the proclamation's intent and harmful to the Lake's ecosystem.

The importance of groundwater to Great Salt Lake has been underscored by recent scientific findings. While in the past, the State considered the groundwater contribution to Great Salt Lake to be relatively insignificant – estimated at around 75,000 acre-feet per year – recent studies by the Utah Geological Survey have increased this estimate to 560,000 acre-feet, a staggering 750% increase. This revelation highlights the vital role that groundwater plays in maintaining the Lake's water levels and overall health.

In an effort to protect this essential water source for the Lake and to encourage the State Engineer to interpret the proclamation correctly, we are challenging applications for new groundwater appropriations that we believe violate the provisions of the proclamation. Click here to read one of our Water Right Application protests.

Our protests meticulously detail why these applications should be rejected, addressing issues such as the lack of unappropriated water in the Great Salt Lake Basin, potential impairment of existing rights, and detriment to public welfare. By challenging these water right applications, we aim to ensure that the intent of the Governor's proclamation is upheld, and that the critical groundwater sources feeding Great Salt Lake are protected for the benefit of the Lake's unique ecosystem and the communities that depend on it.

Listen to a Division of Water Rights hearing for one of our protests from 1/30/25.

Ongoing Work

By challenging groundwater appropriations and insisting on responsible wastewater reuse practices, we are working to ensure that the intent of protective legislation is upheld and that the long-term health of Great Salt Lake remains a priority. These ongoing efforts highlight the critical importance of informed management balancing ecological preservation with human needs.

The Utah Geological Survey recently released the Utah Groundwater Data Hub, an important resource to help us understand groundwater storage and inflows in the state. 

To learn more about the Utah Groundwater Data Hub, you can read this article by Carter Williams of the Great Salt Lake Collaborative:
https://www.ksl.com/article/51093522/new-utah-hub-shines-light-on-states-more-mysterious-water-source

More on Groundwater:
If you've been paying attention to Great Salt Lake news over the last few years, you've likely heard that our understanding of groundwater inflows to the Lake has changed significantly. The most recent estimate, by Hector Zamora and Paul Inkenbrandt estimates that groundwater contributes 313,500 acre feet to Great Salt Lake annually. Because groundwater storage and inflows are notoriously difficult to measure, the growth of this field is important to understanding implications of groundwater storage to the Lake's health. This year, Sam Carter received a Doyle W. Stephens Scholarship for his research on groundwater inflows to Farmington Bay. Click here to watch Sam's presentation on his research at the 2024 Great Salt Lake Issues Forum. 

BYU's Abbott Lab of Ecosystem Ecology worked with a team of 32 researchers and managers to put together an emergency briefing on Great Salt Lake. The briefing provides an overview of the lake's ongoing collapse and call for the establishment of a minimum flow requirement to restore the lake.

View or download the full report as a PDF.

Great Salt Lake is facing unprecedented danger. Without a dramatic increase in water flow to the lake in 2023 and 2024, its disappearance could cause immense damage to Utah’s public health, environment, and economy. This briefing provides background and recommends emergency measures. The choices we make over the next few months will affect our state and ecosystems throughout the West for decades to come. We thank all those already working on solutions, and we thank you for considering this information.

Authors: Benjamin W. Abbott1, Bonnie K. Baxter2, Karoline Busche1, Lynn de Freitas3, Rebecca Frei4, Teresa Gomez1, Mary Anne Karren3, Rachel L. Buck1, Joseph Price1, Sara Frutos1, Robert B. Sowby1, Janice Brahney5, Bryan G. Hopkins1, Matthew F. Bekker1, Jeremy S. Bekker1, Russell Rader1, Brian Brown1, Mary Proteau1, Gregory T. Carling1, Lafe Conner6, Paul Alan Cox7, Ethan McQuhae1, Christopher Oscarson1, Daren T. Nelson8, R. Jeffrey Davis9, Daniel Horns8, Heather Dove10, Tara Bishop11, Adam Johnson12, Kaye Nelson12, John Bennion12, Patrick Belmont5

1Brigham Young University, 2Westminster College, 3Friends of Great Salt Lake, 4University of Alberta, 5Utah State University, 6Wasatch High School, 7Brain Chemistry Labs, Jackson Hole, 8Utah Valley University, 9Integral Consulting, 10Great Salt Lake Audubon, 11Ph.D. Research Ecologist, 12Conserve Utah Valley

Executive summary

1. Great Salt Lake is a keystone ecosystem in the Western Hemisphere. The lake and its wetlands provide minerals for Utah’s industries, thousands of local jobs, and habitat for 10 million migratory birds1–4. Fertilizer and brine shrimp from the lake feed millions of people worldwide5,6. The lake provides $2.5 billion in direct economic activity yearly7–10, as well as increasing precipitation, suppressing toxic dust, and supporting 80% of Utah’s wetlands11–17.
2. Excessive water use is destroying Great Salt Lake. At 19 feet below its average natural level since 1850, the lake is in uncharted territory18–22. It has lost 73% of its water and 60% of its surface area23–26. Our unsustainable water use is desiccating habitat, exposing toxic dust, and driving salinity to levels incompatible with the lake’s food webs1,24,27–29. The lake’s drop has accelerated since 2020, with an average deficit of 1.2 million acre-feet per year. If this loss rate continues, the lake as we know it is on track to disappear in five years.
3. We are underestimating the consequences of losing the lake. Despite encouraging growth in legislative action and public awareness, most Utahns do not realize the urgency of this crisis. Examples from around the world show that saline lake loss triggers a long-term cycle of environmental, health, and economic suffering30–35. Without a coordinated rescue, we can expect widespread air and water pollution, numerous Endangered Species Act listings, and declines in agriculture, industry, and overall quality of life1–4,36.
4. The lake needs an additional million acre-feet per year to reverse its decline. This would increase average streamflow to ~2.5 million acre-feet per year, beginning a gradual refilling. Depending on future weather conditions, achieving this level of flow will require cutting consumptive water use in the Great Salt Lake watershed by a third to a half. Recent efforts have returned less than 0.1 million acre-feet per year to the lake37, with most conserved water held in reservoirs or delivered to other users rather than released to the lake.  
5. Water conservation is the way. While water augmentation is often discussed (pipelines, cloud seeding, new reservoirs, and groundwater extraction, etc.), conservation is the only way to provide adequate water in time to save Great Salt Lake33,38–41. Conservation is also the most cost effective and resilient response42,43, and there are successful examples throughout the region44–48. Ensuring financial, legislative, and technical support for conservation will pay huge dividends during this crisis and for decades to come1,38,46,49.
6. We need to increase trust and coordination. New legislation allows users to return water to the lake while retaining rights50. However, lack of trust and cooperation between farmers, cities, managers, and policymakers is hobbling our response33,38. Users often have financial disincentives to conserve, and farmers often lack legal counsel to navigate policy changes.
7. We call on the governor’s office to implement a watershed-wide emergency rescue. We recommend setting an emergency streamflow requirement of at least 2.5 million acre-feet per year until the lake reaches its minimum healthy elevation of 4,198 feet51. Executive leadership is needed for water leasing, farmer compensation, water donations, and conveyance52. Every major water user needs to be educated, empowered, and assured that their conserved water will be shepherded to Great Salt Lake. We need clear thresholds that trigger binding emergency conservation measures to stop the lake’s collapse.
8. We call on the legislature to fund and facilitate the rescue. Recent bills have laid the groundwork, and a surge of funding is now needed to lease or purchase water and support farmers and cities to dramatically reduce consumption. Likewise, legislation is needed to put in place the policies, accounting, and monitoring for water shepherding to the lake and long-term sustainable water use52.
9. We call on every water user and manager to conserve water and support state efforts. We are in an all-hands-on-deck emergency, and we need farmers, counties, cities, businesses, churches, universities, and other organizations to do everything in their power to reduce outdoor water use. We believe that our community is uniquely suited to face this challenge, but only if we implement a unified and pioneering rescue. By taking a “lake first” approach to water use, we can leave a legacy of wise stewardship for generations to come.

 Click here to read the full report.