GSA 2020 Connects Online

Paper No. 21-8
Presentation Time: 3:20 PM

GIS-BASED HYDROLOGIC ASSESSMENT (HESA) OF THE WATERSHED, GEOHYDROLOGIC FRAMEWORK, AND GROUNDWATER AVAILABILITY AND SUSTAINABILITY OF BEST FRIENDS ANIMAL SOCIETY-CANYON OPERATIONS (BFAS), KANE COUNTY, UTAH


KOLM, Kenneth E., Hydrologic Systems Analysis, LLC, 128 Burgess Ave, Golden, UT 80401, VAN DER HEIJDE, Paul K.M., Consultant, 4040 Greenbriar Blvd., Boulder, CO 80305 and BATTISTA, Bartholomew, Best Friends Animal Society, Kanab, UT 84741

The purpose of this study was to perform a Hydrologic and Environmental System Analysis (HESA) of the Best Friends Animal Society’s animal sanctuary (BFAS) located along Kanab Canyon 7 miles north of Kanab, Utah and ascertain the potential impacts of proposed upgradient land uses on groundwater supply. The HESA, supported by GIS databases and maps, was used to develop an updated Conceptual Model of hydrogeologic and hydrologic characteristics of the groundwater and surface water systems; and to develop a current water budget to be used for water rights defense, numerical modeling activity, and urbanization, mining, and climate-change driven planning affecting the groundwater availability and sustainability of the subregion.

The results of this study are a new conceptual model on how the BFAS hydrologic systems are structured and function with respect to subregional and local fracture and fault zones acting as French drains, as opposed to matrix flow, that dominate the surface water and groundwater flowpaths, storage capacity, and recharge, and ultimately account for the sustainability of these complex hydrologic systems; and how a water balance guided by this conceptualization more accurately represents the properties of the complex hydrologic systems for water rights, management, and modeling purposes. Specific hydrogeological results pertaining to availability and sustainability include: 1) the characterization of the Jurassic Navajo Aquifer - Kanab Creek hydrologic system and the central Kanab Creek drainage and tributaries in terms of connectivity, fracture flow and French drains that control the recharge, storage, and discharge of groundwater in the main bedrock system affecting BFAS’s springs and wells, and 2) the delineation of two separate groundwater systems, one local and one regional, connected mostly by surface water links and fracture zones that compose the central Kanab Creek subregional system. The water balance analyses revealed that direct local recharge from precipitation exceeded 60% of total indicating that the disturbance and removal of eolian cover for industrial use, and climate change resulting in declining precipitation are the most important factors for declining water tables and groundwater supply.