Utah Researchers Reveal Massive Hidden Ice Reserves in Rock Glaciers

Key points

• The Timpanogos rock glacier contains about 1.55 million cubic meters of ice, with an average thickness of 18.8 meters.
• Researchers used gravimeters to measure density differences between ice and rock, bypassing limitations of ground-penetrating radar.
• Rock glaciers release water year-round, offering a stable supply during late summer when snowpack is depleted.
• Utah’s rock glaciers are estimated to hold approximately 1.08 cubic kilometers of ice, a resource not currently included in state water models.
• The ice in these formations is protected by a layer of debris, making it more resilient to warming temperatures than exposed glaciers.

Background

Previous coverage in September 2026 established that Utah’s rock glaciers represent a significant but underrecognized freshwater reserve. Earlier reports noted that while traditional glaciers are melting rapidly, rock glaciers are insulated by rock debris, allowing some to continue accumulating ice. The current study builds on these findings by providing precise volumetric data and confirming the potential for these formations to serve as long-term water storage in a drought-prone region.

How outlets are covering it

KSL News emphasizes the practical benefit of rock glaciers for Utah’s water supply, noting that nearly all surveyed sites had active runoff, which is crucial during severe drought conditions. Gizmodo highlights the global implications, framing rock glaciers as vital 'freshwater savings accounts' that could help mitigate future water scarcity. Eos focuses on the methodological breakthrough, praising the use of gravimetry and Bayesian inversion to map ice that is otherwise invisible to standard radar techniques. While all sources agree on the volume of ice, KSL stresses immediate water availability, whereas Eos and Gizmodo focus on the long-term resilience and scientific novelty of the findings.

Why it matters

As Utah faces persistent drought and over 90% of the state remains in severe drought categories, identifying new water sources is critical. Rock glaciers offer a stable, year-round water supply that is less vulnerable to climate change than exposed glaciers. However, because these reserves are not currently included in state hydrological models, policymakers lack a complete picture of available water resources. Accurately quantifying this hidden ice could inform future water management strategies and provide a buffer against worsening drought conditions in the Mountain West.

What to watch

Researchers plan to apply the gravimetric method to other rock glaciers in Utah and the western United States to validate the findings. They also aim to determine how much of the meltwater from rock glaciers contributes to downstream hydrology versus groundwater, which will help clarify the role of these formations in the broader water cycle. Further studies will investigate whether rock glaciers are still accumulating ice, which could indicate their long-term viability as water reserves.