Geology and Geophysics Department
University of Utah
Bio:
Sam Carter is a first-year master’s student at the University of Utah working under Dr. Kip Solomon. His research uses environmental tracers to understand the age, origin, and flow paths of groundwater inflow to Great Salt Lake. After getting his BSc from the University of Utah in Geoscience, he worked for the National Park Service for three years in Katmai, Lake Clark, Olympic, and Mt. Rainier National Parks. It inspired him to return to the University of Utah to study Great Salt Lake as it simultaneously hit record low levels. Sam hopes his work can help fill-in knowledge gaps in Great Salt Lake's water budget so that water managers, scientists, and politicians can better understand and protect Great Salt Lake ecosystems and Salt Lake Valley residents that depend on a healthy lake. He hopes to be a part of an interdisciplinary, equitable, inclusive, and resilient movement to protect Great Salt Lake for future generations. In his free time, Sam enjoys rollerblading, playing the guitar, and backcountry skiing.
Title: Using Environmental Tracers to Develop a Conceptual Framework of Groundwater Inflow into Farmington Bay, Great Salt Lake, UT
Abstract: Great Salt Lake, UT is one of the largest and most ecologically important water bodies in North America [1,2]. With record low lake levels in recent years, better understanding the water budget of Great Salt Lake is of utmost importance. While surface water inflows are relatively easy to measure, estimates of groundwater inflow are very poorly constrained and have widely been estimated from water budget residuals. Original water budget calculations attributed ~3% of total inflow to groundwater [3]. Recent work has suggested higher inflow percentages, near 10-12% [4, 5]. The uncertainty and inconsistency in groundwater inflow estimates highlights the difficulty in quantifying subsurface flow without a conceptual understanding of the origin, flow paths and discharge zones in the Great Salt Lake catchment. Independent measurements are needed to constrain groundwater contribution in the water budget.
Environmental tracers, especially tritium and dissolved noble gases, are powerful tools for understanding groundwater flow. Manning & Solomon (2003) demonstrated in the Salt Lake Valley that 1) the age of groundwater increases as you move further from the mountain block and 2) most groundwater samples have high recharge elevations [6]. We will apply their methods further north in Farmington Bay, where the discharge zone is presumed to be Great Salt Lake. Age gradients determined from tritium will be used to estimate the average linear flow velocity of groundwater towards Farmington Bay (the southeast arm of Great Salt Lake). Dissolved noble gases will be used to determine the recharge elevation (ie. origin) of groundwater throughout our study area. These results will be integrated with aerial thermal imagery (to determine areas of discrete groundwater inflow), electrical resistivity tomography (to determine areas of subsurface freshwater and saltwater), and water level measurements (to determine hydraulic gradients) to develop a more robust understanding of groundwater inflow to Great Salt Lake.
References:
- Jewell, Paul "Historic Low Stand of Great Salt Lake, Utah: I." SN Applied Sciences 3.8 (2021): 757-16.
- Anderson, B. et al. “Quantity and Quality of Groundwater Discharge in Hyper-saline Lake Environment, Great Salt Lake, Utah, USA.” Journal of Hydrology 512 (2014): 177-194.
- Waddell, M. and Barton, J. D. “Estimated inflow and evaporation for Great Salt Lake, Utah, 1931-76 : with revised model for evaluating the effects of dikes on the water and salt balance of the lake. (Cooperative investigations report ; no. 20).” (1980).
- Bunce, L.E.. “Significance of Spring Inflow to Great Salt Lake.” Binghamton, Binghamton University (2022),p. 64 M.S. thesis.
- Zamora, A., and Inkenbrandt, C.I. “Estimate of Groundwater Flow and Salinity Contribution to Great Salt Lake Using Groundwater Levels and Spatial Analysis: Utah Geological Association Publication”. (2024).
- H. Manning, D.K. Solomon. “Using Noble Gases to Investigate Mountain Block Recharge.” Journal of Hydrology 275 (2003): 194-207