Aquifer Recharge and Water Resource Assessment
Location
Walla Walla Basin,
Oregon and Washington
Client
Walla Walla Basin Watershed Council
Project Description
GSA hydrogeologists have applied and calibrated a basin-scale (239 mi2) surface water-groundwater model using the Integrated Water Flow Model code. The basin has seen a long-term decline in water table elevations and endangered fish populations. Managed aquifer recharge is being implemented to stabilize and augment groundwater supplies to reduce demand on surface water during low flow periods, thereby improving fish habitat by increasing flow. The calibrated model is being used to predict the effect of increasing and/or expanding aquifer recharge at various locations and also to evaluate other management strategies such as canal piping, water exchanges, surface water storage, and irrigation efficiency improvements. Model results are used to support the selection of management strategies to maintain and improve river flows that also support agricultural needs.
Project Highlights
- Estimate basin-wide water resource distribution and usage
- Develop basin-scale IWFM surface water-groundwater model
- Calibrate IWFM basin model to groundwater elevation and surface water flow data
- Evaluate water management strategies effect on stream habitat and groundwater conditions
