U.S. Department of the InteriorU.S. Geological SurveyWater Resources

Jack Eggleston and Verne SchneiderJune 22-23, 2013

Groundwater SciencePotential Activities in the

Mountain Aquifer of the Eastern Basin

A Safe and Sustainable Groundwater Supply Depends on:

• Scientific understanding of ground water

• Water use planning and practices based on science

• Monitoring

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

Examples of Groundwater Science in Other Stressed Aquifer Basins

CaliforniaCentralValley

Middle RioGrand Basin

Columbia RiverPlateau

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

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

Real-time Monitoring Online

California Central Valley – Groundwater Budget

• Outflow mostly to agricultural wells pumping• Inflow mostly from recharge

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California Central Valley – Groundwater Model

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/

Examples of Groundwater Science in Other Stressed Aquifer Basins

CaliforniaCentralValley

Middle RioGrand Basin

Columbia RiverPlateau

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

Middle Rio Grand Basin – Study

• Data compiled• Natural tracers used to

measure groundwater flowpaths and ages

• Existing MODFLOW models updated

• 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:

Examples of Groundwater Science in Other Stressed Aquifer Basins

CaliforniaCentralValley

Middle RioGrand Basin

Columbia RiverPlateau

U.S. Department of the InteriorU.S. Geological SurveyWater Resources

OnlineGeologic Model

Geology is Known

BoreholeLogsUsed toBuild 3DGeologic Model

Elevation surfaces generated to represent each hydrogeologic unit

Model provides 3D geology representation of layers and faults

Model is available onlinehttp://or.water.usgs.gov/proj/cpras/index.html

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

Applications to the Eastern Basin

• Monitor –

• Map –

• Model –

• Assess and Predict –

• Connect Science to Management -

• Continue Monitoring -