2016 Salt Lake County Watershed Symposium

Groundwater Development and Surface Water: Streamflow Depletion
Groundwater and surface-water resources are often connected. Much has been written about the effects of groundwater development on surface water, and new tools are available to simulate and quantify these effects. In this study, a numerical groundwater flow model was used to prepare capture maps to illustrate the connection between groundwater development and surface water. Capture maps show the amount of surface-water depletion caused by a well at any location in the model domain and can be used by water managers to assess the impacts of groundwater development. The first part of this presentation gives a brief synopsis of the source of water to wells and common misconceptions about surface-water depletion. The second part presents the development and analysis of capture maps for a basin dominated by surface-water features. Rather than analyzing depletion in only one river or spring, this work uses one set of capture simulations to determine the effects of groundwater development on 11 segments along two rivers, 30 springs, 13 areas of field drains, and 3 areas of evapotranspiration of groundwater. The presentation concludes with a discussion of the implications of the capture maps and suggestions on how this type of analysis can be used by water managers.