Groundwater - Surface Water Interaction and

Contaminant MovementTeacher Workshop March 13, 2015

UNC-CH

Amy Keyworth

NCDENR Division of Water Resources

Division of Water Resources

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

Exploring Geology by ReynoldsJohnsonKellyMorinCarter

Resources

http://water.usgs.gov/education.html Google images – USGS losing stream

Acknowledgements

Christine Blanton Lawson (NCDENR DWR) Evan Kane (NCDENR DWR) Ben Mirus (USGS)

Oceancurrents

Glaciers

Clouds and precipitation

Flowing water

LakesGroundwater

Oceans

Biological water

Water in minerals

Where is the water?

How Does Water Move?

How Does Water Move?

Air currents

Evaporation

Condensation

Precipitation

Runoff

Infiltration (recharge)

Groundwater discharge

Transpiration from plants

How Does Water Move?

Air currents

Evaporation

Condensation

Precipitation

Runoff

Infiltration (recharge)

Groundwater discharge

Transpiration from plants

Water Balance Equation – Inputs = Outputs

Distribution of Water

Estimated Water Age

Residence Time

Oceans and seas @ 4000 years

Lakes and reservoirs @ 10 years

Swamps 1-10 years

Rivers @ 2 weeks

Soil Moisture 2 wks to 1 yr

Groundwater 2 wks to 10,000 yrs

Icecaps and glaciers 10-1,000 yrs

Atmospheric Water @ 10 days

Source: Nace, 1971

Millions

Groundwater Age

http://en.wikipedia.org/wiki/File:Groundwater_flow.svg

Water Use in U.S.

Groundwater Between Grains

Most groundwater in pore spaces between grains and clasts

Below, pores saturated with groundwater

Pores in upper parts generally unsaturated

Top of saturated zone is water table

17.03.a1

Infiltration

Groundwater flow

Evapotranspiration

Precipitation Surface runoff

Wetlands and lakes

Reach water table and saturated zone

How Does Groundwater Accumulate?

17.03.b1

Needed for groundwater to flow

• Change in elevation or pressure (head)

• Porosity

• Permeability

Porosity: Proportion of Open Space

Which of the following have lower porosity and which have higher porosity?

Crystals in granite fit tightly

Clay particles do not fit tightly

Rounded, sorted clasts do not fit tightly

Poorly sorted clasts fit more tightly

High porosity

Low porosity

Lower porosity

High porosity

Permeability: Pores Connected So Fluids Flow

Granite with many fractures

Loosely cemented gravels

Compacted clay (shale)

Porous volcanic rock with isolated pores

High permeability

Low permeability

http://techalive.mtu.edu/meec/module06/Porosity.htm

http://techalive.mtu.edu/meec/module06/Permeability.htm

http://techalive.mtu.edu/meec/module06/Packing.htm

http://techalive.mtu.edu/meec/module04/GroundwaterSpeed.htm