The Great Salt Lake is shrinking, exposing over 800 square miles of lakebed and contributing to dangerous dust storms across northern Utah. But beneath the increasingly saline surface, a team of researchers at the University of Utah has discovered a significant freshwater reservoir, offering a potential recent tool in the fight to stabilize the lake and mitigate the growing public health crisis. The discovery, published in February in the journal Scientific Reports, could reshape how the state approaches water management and dust control in the face of ongoing drought.
The research, led by distinguished professor of geology and geophysics Michael Zhdanov, utilized airborne electromagnetic surveys to map the subsurface of Farmington Bay, a portion of the Great Salt Lake. These surveys, conducted by flying specialized equipment from a helicopter, allowed scientists to “see” through the highly conductive saltwater and identify areas of freshwater saturation as deep as 10,000 to 13,000 feet below the surface. This breakthrough demonstrates the potential of this technology to locate similar freshwater resources beneath other terminal lakes facing similar challenges.
“We were able to answer the question of how deep this potential reservoir is, and what its spatial extent is beneath the eastern lake margin,” explained Zhdanov. “If you know how deep, you know how wide, you know the porous space, you can calculate the potential freshwater volume.” Although the exact volume remains to be determined, the initial findings suggest a substantial resource exists, trapped within porous rock formations.
The Curious Case of the Phragmites
The impetus for the study came from an unexpected source: the proliferation of phragmites, a highly invasive reed, across the exposed lakebed. Researchers noticed these plants thriving in areas where other vegetation struggled, suggesting a source of freshwater was sustaining them. “These very strange plants – they use a lot of fresh water,” Zhdanov said. “So, where does this water come from? It looks like this water comes from underground.”
Dust Mitigation and Potential Irrigation
The implications of this discovery are significant, particularly in the context of the lake’s declining water levels and the resulting dust pollution. As the lake shrinks, exposed lakebed, rich in heavy metals, becomes a source of airborne particulate matter, posing a serious health risk to nearby communities. According to the Utah Department of Environmental Quality, dust from the Great Salt Lake contributes significantly to poor air quality in the Wasatch Front.
Zhdanov emphasized that the “reservoir” isn’t a traditional underground lake, but rather porous rock saturated with freshwater. “In principle, you may drill this and you can pump this water on the surface and use it to mitigate dust pollution blowing from the lake surface and, possibly, in irrigation,” he said. Although, he cautioned that careful study is needed before any extraction begins.
Bill Johnson, a hydrologist at the University of Utah and co-author of the study, echoed this sentiment. “There are beneficial effects of this groundwater that we need to understand before we go extracting more of it,” Johnson said in a statement. “A first-order objective is to understand whether we could use this fresh water to wet dust hotspots and douse them in a meaningful way without perturbing the freshwater system too much.”
Expanding the Search and Securing Funding
The initial study focused on a relatively small area of Farmington Bay. Researchers believe a more comprehensive survey of the entire 1,500-square-mile lakebed could reveal the full extent of the freshwater resource and inform regional water-resource planning. Zhdanov envisions expanding the airborne electromagnetic surveys across the entire lake, and potentially throughout the state, to identify other hidden groundwater reserves. “We have a desert here. This desert could hide fresh water… We know this happens in the Sahara, we know this happens in Africa and this may happen here,” he said.
However, realizing this vision requires funding. Zhdanov and Johnson are actively seeking support from the Utah Legislature and the Utah Department of Natural Resources to expand their research. Preliminary discussions have already begun, but securing the necessary resources will be crucial to unlocking the full potential of this discovery.
The discovery of this freshwater reservoir represents a glimmer of hope in the face of the Great Salt Lake’s ongoing crisis. While significant challenges remain, the potential to mitigate dust pollution and augment water resources offers a path forward for a more sustainable future. The next step involves a detailed assessment of the reservoir’s volume, recharge rates, and potential impacts of extraction, a process expected to initiate pending funding approval in the coming months.
What are your thoughts on this discovery? Share your comments below and let us know how you believe this freshwater reservoir could impact the future of the Great Salt Lake.
