Conner, Abigail E听1听;听Gooseff, Michael N听2听;听Chen, Xingyuan听3
1听Institute of Arctic and Alpine Research (INSTAAR), and Department of Civil, Environmental, & Architectural Engineering, University of Colorado Boulder, Colorado
2听Institute of Arctic and Alpine Research (INSTAAR), and Department of Civil, Environmental, & Architectural Engineering, University of Colorado Boulder, Colorado
3听Pacific Northwest National Laboratory, Richland, Washington
Rivers exchange water with adjacent aquifers. These river-groundwater interactions provide important exchanges of energy, biota, and solutes between the surface and subsurface environments. These processes support fisheries and removal of some pollutants from rivers. We are studying the river-groundwater exchange in the Columbia River corridor in Eastern Washington. This project aims to determine if there is a clear relationship between the water management activities within and beyond the river corridor to the groundwater inflows in the river channel. Since there are many challenges to using applied tracers in a large river system, this project aims to use natural tracers to determine locations of groundwater inflows. Water quality and GPS data was collected along the river corridor using a boat survey to identify locations of groundwater inflows. Water quality measurements taken along the river corridor at depth indicate the presence of groundwater inflows at the riverbed at several locations along the corridor. These locations are compared against locations of irrigation return flow and lateral contributing area to the exchange to identify the influence of each on river-groundwater exchange . Water quality measurements will continue to be collected through varying water management seasons (irrigation and non-irrigation) seasons, to estimate the impact of irrigation on groundwater inflows into the river system. These measurements will also be used to calibrate models of hydrologic exchange developed by the River Corridor SFA at the reach scale of the Columbia River. This research will advance knowledge about the connection of landscape management to large river systems.