Frequently Asked Questions

Here is Grow the Flow’s guide to the most commonly asked questions about Great Salt Lake — from interesting facts to the serious realities of what’s at stake.

How did Great Salt Lake form?

It’s a remnant of ancient Lake Bonneville, a massive Ice Age lake that once covered much of western Utah and parts of Nevada and Idaho. About 14,500 years ago, the lake catastrophically breached its natural dam at Red Rock Pass in Idaho—possibly triggered by a seismic event—causing one of the largest known floods in the Earth’s history. Great Salt Lake, Utah Lake, and Sevier Lake are among the remnants of ancient Lake Bonneville.

Why does Great Salt Lake smell?

Great Salt Lake smells because it’s a shallow, salty basin with no outlet, so minerals, dead algae, brine shrimp, and other organic matter collect and decompose there. This releases hydrogen sulfide gas, which has a “rotten egg” odor. The smell is strongest in summer heat or when wind stirs up sediments, and it can be more noticeable now with lower water levels exposing more decaying material.

Are there really shrimp in the lake?

Yes—but they’re tiny brine shrimp, not the kind you’d find on your dinner plate. These shrimp are a crucial part of the lake’s food web, feeding millions of migratory birds. Utah’s brine shrimp industry also harvests their cysts (eggs) and sells them worldwide as feed for farmed fish and shrimp.

What are brine flies and will they bug me?

Brine flies are tiny, harmless insects that live along Great Salt Lake’s shoreline. In summer, you might see them hovering in dense clouds near the water’s edge, especially around rocks or wet sand. Unlike other bugs that live around the lake —brine flies don’t bite, sting, or swarm! They’re also an essential food source for millions of migratory birds, making them a keystone species in the lake’s ecosystem.

Why is Great Salt Lake shrinking?

80% of Great Salt Lake’s decline is driven by human water consumption upstream of the lake. Upstream diversions take about two-thirds of its natural inflow, with roughly three-quarters of that diverted water used for agriculture and the rest for cities and industry. Drought and warmer temperatures worsen the problem, but human use is the primary cause.

Why can't we just pipe in water from somewhere else?

Engineering-wise, importing water from the Pacific Ocean or other basins is possible, but studies show it’s astronomically expensive and energy-intensive. An ocean pipeline would cost tens of billions of dollars to build, demand hundreds of megawatts (≈ 11% of Utah’s electricity), produce over a million tonnes of CO2 annually, and bring major regulatory and environmental hurdles. Utah DNR has deemed it unrealistic at present. 

Pipelines from neighboring basins such as the Snake River drainage are also technically feasible, but are hung up by a simple question: If you lived in a neighboring state grappling with population growth and water insecurity, would you be willing to give your “excess” water to Utah?

What happens if the lake keeps shrinking?

If the lake continues to shrink, salinity will climb beyond what brine shrimp and brine flies can survive, collapsing the food chain for millions of migratory birds. The exposed lakebed can fuel dust storms that carry arsenic, mercury, and other pollutants into nearby communities—resulting in increased respiratory and other illnesses. Industries that depend on the lake’s minerals and brine shrimp harvests would face steep cutbacks or closure, while dust pollution and a smaller lake could shorten ski seasons, impact Utah’s real estate value, and disrupt the outdoor recreation economy. The loss of the lake would ripple through every part of the state’s environment, economy, and public health.

How much water does Great Salt Lake need to reach a healthy level?

Scientists estimate the lake needs an additional 1 million acre-feet of water per year to reach and sustain a healthy elevation—ideally above 4,198 feet above sea level. This will require a ~30% decrease in consumptive water use across the basin

Does Great Salt Lake impact our snowpack?

Yes! Great Salt Lake helps generate “lake-effect snow,” where cold air passing over the lake picks up moisture and dumps it as snow on the Wasatch Mountains. As the lake shrinks, that snow-generating effect weakens—reducing the snowpack that Utah depends on for water supply. Great Salt Lake provides 5-10% of the snow in the Wasatch, and up to 50% of the annual precipitation in the Salt Lake Valley.

What health problems are caused by breathing in Great Salt Lake dust?

Breathing dust from Great Salt lake can cause or worsen a range of health problems, including asthma, bronchitis, pneumonia, and cardiovascular issues like heart attacks and strokes. The lakebed contains fine particles (PM10 and PM2.5) and toxic metals such as arsenic, lead, and copper, which become airborne when the lake dries and the wind blows. Lab studies show this dust triggers inflammation and immune responses in lung tissue, and recent research links exposure to systemic inflammation, low birth weight, and even depression. Scientists are also concerned about long-term cancer risks: several of the metals found in the dust are known carcinogens, and while no definitive link has been established yet, experts warn that prolonged exposure could increase the risk of lung, bladder, and skin cancers—especially for communities living downwind.

What mineral are extracted from Great Salt Lake and why are they important?

Great Salt Lake is a major source of minerals like magnesium, sulfate of potash, and salt. Companies extract these by pumping lake water into solar evaporation ponds, where sunlight and wind naturally separate out the minerals. Magnesium is used in lightweight metals for cars and electronics, sulfate of potash is a premium fertilizer for fruits and vegetables, and salt supports chemical manufacturing and road de-icing. The lake is also being explored as a future domestic source of lithium, a critical component in batteries. These mineral resources play a key role in both Utah’s economy and global supply chains.

How much of the Lake’s shrinking is caused by drought and climate change? How much is caused by human water use?

The vast majority of Great Salt Lake’s decline is caused by human water use, not climate change. Consumptive uses—primarily for agriculture, along with some urban and industrial demands—have reduced inflows by about 39%, lowering the lake by 11 feet, shrinking its surface area by 51%, and reducing its volume by 64%. Climate change has contributed to the lake’s decline by increasing evaporation, but its total impact so far is relatively small—accounting for only about 9% of the long-term loss.

How do I get involved with ongoing efforts to save Great Salt Lake?

There are many different ways to make a difference! 

  • Sign up for Grow the Flow’s newsletter, which will give you the inside scoop on community advocacy, events, and education around the lake’s recovery every week.
  • Contact your state legislators and urge them to support policies that protect Great Salt Lake.
  • Volunteer! Grow the Flow offers tailored volunteer opportunities to match your interests and strengths—from tabling and cleanups to birding tours. Got an event idea? We’ll help you bring it to life. 
  • Join or start a local chapter to collaborate on initiatives like community events and legislative campaigns. 
  • Attend public meetings like community forums, city council meetings, public hearings, and chapter meetings to voice your opinion and connect with other community members and activists.
  • Donate! Your donation helps fuel grassroots advocacy, policy work, education, and public engagement around Great Salt Lake.
  • Spread the word by talking to your friends, family, faith communities, and neighbors about what’s happening to Great Salt Lake and why it matters. Post on social media! The more people who understand the stakes, the more momentum we build toward change.
  • Lobby with us. During the Utah legislative session, Grow the Flow organizes weekly public advocacy days at the State Capitol, where volunteers meet directly with lawmakers to advocate for bold action to save the lake
  • Xeriscaping: Replace your water-thirsty lawn—or park strips—with low-water landscapes and earn up to $3 per square foot in rebates through Utah Water Savers’ Landscape Incentive Program.

When is Utah's legislative session?

Utah’s legislature convenes each year in a General Session, which traditionally begins on the fourth Monday in January and runs for 45 calendar days—excluding holidays like Presidents’ Day. The session typically ends in early to mid-March.

How much water can I save by getting rid of my grass lawn?

Use this Water Savings Calculator to determine how much water (and money!) you can save if you get rid of your grass lawn or take advantage of other water-saving rebates. Even replacing just a narrow park strip can conserve 5,000–8,000 gallons annually.

Why is Great Salt Lake so salty?

Great Salt Lake has no outlet. Rivers bring in fresh water and minerals, but as water evaporates, the minerals—including salt—are left behind. Over thousands of years, the salt has concentrated to the point where salinity levels can reach 5-27%, depending on location and season.

How deep is Great Salt Lake?

Great Salt Lake is surprisingly shallow for its size. The lake averages only about 14 feet deep, with the deepest points in the South Arm reaching around 33 feet. Because it’s so shallow, the lake’s depth changes dramatically with fluctuations in water level. In wet years, it can deepen and spread over a larger area, while in dry years—like during its 2022 record low—much of the lake becomes just a few feet deep, exposing large stretches of lakebed. Its shallow nature is part of what makes Great Salt Lake so sensitive to water consumption and changes in runoff. 

How salty is the lake compared to the ocean?

Ocean water averages about 3.5% salinity (35 g/L). Great Salt Lake ranges from about 5% up to 27–30% depending on its water level and location. That’s roughly 3.5 to 8 times saltier than seawater.

Why is the lake two different colors?

A railroad causeway built in 1959 divides the lake into a north arm and a south arm, with limited water exchange between them. The north arm is much saltier—too salty for most organisms except halophilic (salt-loving) algae and bacteria, which give the water a deep pink hue. The south arm is less salty and supports different algae species, which make the water appear blue‑green.

What kind of wildlife depends on Great Salt Lake?

Great Salt Lake is a vital stopover for about 12 million migratory birds each year along the Pacific Flyway, including Wilson’s phalaropes, eared grebes, American avocets, and pelicans. Many species rely on the lake’s brine shrimp and brine flies to fuel their long journeys. The surrounding wetlands also support coyotes, mule deer, muskrats, frogs, toads, and a rich variety of insects, making the lake one of North America’s most important and diverse wildlife habitats.

I remember when the lake flooded in the 1980s, won't that just happen again?

Great Salt Lake’s flooding in 1983 was caused by several abnormally wet winters and cooler temperatures that delayed runoff, sending massive inflows to the lake. These wet years were seen as 1 in 1000 year events. Today, conditions are the opposite—decades of drying, warmer temperatures, and heavy upstream water use keep inflows low. While rare wet years could cause temporary rises, without major conservation efforts the lake is unlikely to return to or sustain 1980s levels.

Why can't we just use cloud seeding?

Cloud seeding aims to increase precipitation by releasing silver iodide particles into clouds to encourage ice crystal formation. While it can slightly boost snowfall in some years, it cannot reliably deliver the enormous volumes of water the Great Salt Lake needs—one million acre‑feet annually.

We also don’t fully understand all the long‑term consequences of large‑scale weather modification. Like other forms of geoengineering, cloud seeding could have unintended ripple effects on local and regional climate patterns, precipitation timing, or ecosystems. The safest, most effective path is not to gamble on high‑tech fixes, but to live within our means— by conserving the water we already have.

How much water is used by agriculture, industry, and Utah residents?

Agriculture accounts for roughly 64% of consumptive water use in the Great Salt Lake watershed. Municipal and industry account for another 16%, followed by managed wetlands (12%), mineral extraction (7%), and reservoir losses (1%).

What can urban residents do for Great Salt Lake?

Urban Utahns can:

Contact your elected officials and speak up for the lake

How much money does the Great Salt Lake economy generate each year?

The Great Salt Lake directly contributes an estimated $2.5 billion to Utah’s economy each year, supporting roughly 9,000 jobs across industries like mineral extraction, brine shrimp harvesting, and outdoor recreation. Evaporation from Great Salt Lake increases annual snowfall in nearby mountains by 5-10%, supporting another 20,000 jobs and an additional $1.8 billion in annual economic activity from the ski industry.

How do I reach out to my legislators and ask them to support Great Salt Lake?

You can take effective civic action in just a few steps. First, find your state representative and senator using the Utah Legislature’s lookup tool. Then visit Grow the Flow’s guide for tips on writing a strong message—be clear, concise, respectful, and include that you’re a constituent. You can also check out our legislative outreach page for updates on priority bills and tips on talking points. Your voice matters—reach out today!

What can be done to help farmers conserve water and get it to Great Salt Lake?

Farmers are essential partners in restoring Great Salt Lake, and many are already stepping up to conserve water. There are several types of water transactions that can help increase flows of water to Great Salt Lake. The Great Salt Lake Watershed Enhancement Trust facilitates voluntary water transactions—such as split-season leasing, M&I water leasing, and water donations—to sustain the lake and its wetlands.

Through programs like Utah’s Agriculture Optimization Fund, farmers can receive up to 75% of the cost to upgrade to more efficient irrigation systems like subsurface drip or automated surge irrigation. These improvements can reduce water usage by 15–30%, though that water doesn’t always make it to the lake. 

Utah must invest in tools and policies to accurately measure water savings, clarify legal protections for water rights, and establish strong shepherding rules to ensure leased water actually reaches the lake. For questions or inquiries about participating in water transactions that could benefit Great Salt Lake, please email GSLWET@audubon.org. You can also visit www.gslwatertrust.org/water-transactions to learn more about the evaluation criteria for water

How much of Utah's water supply comes from snowpack?

Snowpack provides about 95% of Utah’s water, with spring snowmelt feeding the rivers, reservoirs, and aquifers that supply homes, farms, and ecosystems. In this dry state, most precipitation falls as mountain snow in winter, making seasonal runoff essential for year-round water needs.

What is a water right? Prior appropriation? Use it or lose it?

A water right is a legal authorization to use a specific amount of water from a particular source—such as a river, stream, lake, or groundwater—for a defined purpose like irrigation, municipal use, or industry. The water right does not give you ownership over a certain amount of water—which is a public resource—it gives an individual the entitlement to divert and consume water for a beneficial use. 

In Utah and most of the western U.S., water is managed under the prior appropriation doctrine, often summed up as “first in time, first in right.” This means the first person to legally divert water for a beneficial use has priority over later users during shortages.

Utah also follows a “use it or lose it” principle—if a water right isn’t used for its approved purpose over a set period (typically seven years), it can be forfeited or reassigned to someone else. This system is designed to prevent waste and ensure water is put to beneficial use, but it can also create challenges for conservation in a time of growing scarcity.

Recent reforms aim to fix that: the Utah Water Banking Act (2020) allows water rights holders to temporarily lease unused water without losing their rights, and HB 33 (2022) recognizes in-stream flows as a “beneficial use,” so water can be left in rivers or leased without risk of forfeiting their water rights.

Are there any state programs to cover the cost of switching from lawns to a water-efficient yard?

Yes! Utah offers several programs to help cover the cost of replacing grass lawns with water-efficient landscaping. The largest is the Utah Water Savers Landscape Incentive Program, which provides rebates of up to $3 per square foot for removing qualifying turf and replacing it with drought-tolerant plants, drip irrigation, and other water-wise features. 

Many local water districts and cities—including those in Salt Lake County, Weber Basin, and Washington County—also run their own “flip your strip” or turf buyback programs, sometimes offering additional rebates for converting narrow park strips or entire lawns. 

Utah also promotes water conservation through Slow the Flow, an educational campaign that offers free sprinkler system efficiency checks, seasonal watering guides, and other tools to help residents use less water without necessarily changing their landscaping. These incentives help homeowners save thousands of gallons of water each year, lowering long-term water bills while creating more sustainable yards.