Geohydrologic Framework and Assessment of Aquifer Characteristics of the Big Sioux Aquifer and Groundwater Flow Model to Determine Sustainable Yield for the City of Sioux Falls

Science Center Objects

Project Period: 2015-18
Cooperators: City of Sioux Falls
Project Chief: Greg Delzer

Executive Summary

The City of Sioux Falls requires a sustainable supply of municipal water to meet current and future demands to support economic development and population growth. Groundwater is an important component of the City‘s supply. Management of sustainable groundwater supplies is contingent upon characterization of groundwater availability. The determination of sustainable groundwater supplies is also a high scientific priority for the USGS.

Modeling areas affected by glaciation often pose several challenges.  One such challenge includes modeling buried channels that are not identifiable from surface geology because they are often covered by glacial drift. Several non-invasive geophysical methods will be used to characterize the Big Sioux aquifer in the area of the Sioux Falls airport and north to Dell Rapids.

Objectives

The primary objectives for the study include: (1) characterizing the geohydrologic framework of the Big Sioux aquifer in the vicinity of Sioux Falls, South Dakota; and (2) development of a groundwater flow model to assess sustainability.  

Short-term benefits of this study include characterizing the geohydrologic framework of the Big Sioux aquifer. Longer term benefits include a groundwater model that can evaluate various stress scenarios for future well development. The overall study results can provide information on groundwater supplies and what potential effects pumping may have on other production wells and the Big Sioux River. More specifically, primary benefits include:

  • a clear delineation of groundwater resources in the Big Sioux aquifer,
  • accurate estimates of groundwater model input parameters (for example, saturated thickness, specific yield, porosity),
  • simulated information on the potential effect of pumping a hypothetical well(s) on existing production wells,
  • prediction of the fate and transport of contaminant plumes, and
  • visualization of streamflow capture indicating areas that are more vulnerable to contamination and potential effects on the Big Sioux River.