By: S. M. Kirby
Recent residential growth in unincorporated portions of San Juan County north and east of Blanding utilizes ground water derived primarily from sandstone of the undivided Dakota and Burro Canyon Formations for culinary water. The primary source of recharge to the bedrock aquifer may be seepage from unlined irrigation canals and reservoirs along the northern extent of the study area, but the relative contribution of seepage to total recharge is unknown. Potential installation of a pipe system for water delivery along the northern canal could decrease recharge from seepage and adversely affect ground-water availability at culinary wells near Blanding.
The goal of this study is to characterize the geologic framework of the Dakota-Burro Canyon aquifer and adjacent units and estimate the relative amounts of artificial and natural recharge for this aquifer. The scope of work for this project included new geologic mapping based on color air photos and extensive fieldwork, new measured stratigraphic sections of the principal aquifer, and well-log analysis. Hydrologic and geologic framework data presented in this report will support informed resource management decisions and provide basic data necessary for future numerical modeling of groundwater flow in the principal aquifer.
Pages: 48 p.
Plates: 4 pl.
Location: San Juan County