1. U.S. Department of the Interior U.S. Geological Survey Water Resources Jack Eggleston and Verne Schneider June 22-23, 2013 Groundwater Science Potential Activities in the Mountain Aquifer of the Eastern Basin

2. A Safe and Sustainable Groundwater Supply Depends on: Scientific understanding of ground water Water use planning and practices based on science Monitoring

3. Groundwater Science Approach Monitor – collect data to build a foundation Map – display the data Model – develop mass balance models to understand and predict groundwater processes Assess and Predict – understand how management policies will affect water resources Connect Science to Management - publish study results, present to regulators Continue Monitoring – to reassess and modify management practices

4. Examples of Groundwater Science in Other Stressed Aquifer Basins California Central Valley Middle Rio Grand Basin Columbia River Plateau

5. California Central Valley Semi-Arid – 300 mm/yr precip Population increasing, from 1985-2005 population doubled Large groundwater withdrawals Water level declines and salinization are problems Water restrictions cause debate Complex management options Better understanding and tools were needed

6. California Central Valley- Groundwater Science Program Monitoring – Water levels Water use Water quality Land Use and Climate GIS Database Construction and Data Analysis Compartmentalized Model– Groundwater Surface Water Land Use Water Use and Management

7. Real-time Monitoring Online

8. California Central Valley – Groundwater Budget Outflow mostly to agricultural wells pumping Inflow mostly from recharge 1000’s of MCM 1 2 3 4 5 -2 -3 -4 -5 0

9. California Central Valley – Groundwater Model

10. California Central Valley Groundwater – Study Report Study is the basis for planning and regulation Model used as tool by regional water managers Monitoring continues to measure changing conditions and effects of management actions http://pubs.usgs.gov/pp/1766/

11. Examples of Groundwater Science in Other Stressed Aquifer Basins California Central Valley Middle Rio Grand Basin Columbia River Plateau

12. Middle Rio Grand Basin Water use regulated by both state and federal agencies Groundwater is primary drinking water supply Semi-arid, 275 mm/yr precip Competition for scarce water Groundwater levels declining Better understanding needed for water supply planning

13. Middle Rio Grand Basin – Study Data compiled Natural tracers used to measure groundwater flowpaths and ages Existing MODFLOW models updated

14. Aquifer not being replenished as quickly as had been assumed Less ground water available in storage than previously believed Results provide basis for comprehensive local water policy Middle Rio Grand Basin – Study Results http://pubs.usgs.gov/circ/2002/circ1222/ http://pubs.usgs.gov/wri/wri03-4286/ Public Reports:

15. Examples of Groundwater Science in Other Stressed Aquifer Basins California Central Valley Middle Rio Grand Basin Columbia River Plateau

16. U.S. Department of the Interior U.S. Geological Survey Water Resources Online Geologic Model

17. Geology is Known

18. Borehole Logs Used to Build 3D Geologic Model

19. Elevation surfaces generated to represent each hydrogeologic unit

20. Model provides 3D geology representation of layers and faults

21. Model is available online http://or.water.usgs.gov/proj/cpras/index.html

25. Groundwater Science Approach Monitor – collect data to build a foundation Map – display the data Model – develop mass balance models to understand and predict groundwater processes Assess and Predict – understand how management policies will affect water resources Connect Science to Management - publish study results, present to regulators Continue Monitoring – to reassess and modify management practices

26. Applications to the Eastern Basin Monitor – Map – Model – Assess and Predict – Connect Science to Management - Continue Monitoring -