Characterization of Groundwater in Johns and Emery Valleys, Garfield and Kane County, Utah, With Emphasis on the Groundwater Budget and Groundwater–Surface-Water Interaction (SS-172)

By: Janae Wallace, Trevor H. Schlossnagle, Kathryn Ladig, Paul C. Inkenbrandt, Hugh Hurlow, and Christian Hardwick

Johns and Emery Valley are located in Southwestern Utah in a scenic and beautiful area with a Pristine Classified aquifer (TDS < 500 mg/L) that serves nearby Bryce Canyon National Park. Water quality, quantity, and the potential for water-quality degradation are critical elements that may determine the extent and nature of future tourism-driven development in these valleys. Our data show a connection between surface water and groundwater in the valley-fill aquifer based on shared geochemical characteristics, isotopic tracer signatures, increases in water levels in wells in direct response to heavy precipitation seasons, and seepage run measurements showing streams with distinct gaining and losing reaches. A soil-water balance model shows the interaction between surface water and the sediments of the valley-fill aquifer. A basin-wide SWB shows the greatest source of recharge is from adjacent mountain bedrock and surrounding runoff followed by precipitation; discharge is dominantly from groundwater seepage to the East Fork Sevier River at the northern boundary followed by ET and well water withdrawals; average recharge to the valley-fill aquifer is ~ 9200 acre-feet/yr and average net loss is ~ 11,000 acre-feet/yr from 2017 to 2021, a time period characterized by drought. Although the long-term change in storage has been close to zero, we recommend careful water resource management for future development given the observed quick response of groundwater levels to climate conditions on shorter timescales. Because of the potential increase in growth from tourism-related development, an increased demand for drinking water warrants continuous monitoring that will assist land-use planning and resource management to maintain local water resources.

Other Information:
Published: 2024
Pages: 76
Appendices: 7
Location: Utah
Media Type: Paper Publication