1. Water

2. Water Cycle
Evaporation is the process in which liquid bodies of water, such as ponds, lakes, rivers, and oceans, change into water vapor.
Transpiration is the evaporation of water from plant leaves.
Condensation is the next process. In condensation the water vapor changes to liquid water or ice. The clouds are formed due to condensation.
Precipitation is when the water condenses so much that it falls to the ground in the form of rain, snow, or hail.
Once the precipitation falls to the ground, the water may infiltrate (infiltration) into the ground OR
Once the precipitation falls to the ground, the water may flow onto the ground (runoff) into lakes, streams, rivers oceans, or ponds.
Once in these bodies of water, evaporation occurs and the process starts all over again.

4. Distribution of Groundwater
Groundwater: Belt of soil moisture
Zone of aeration
Unsaturated zone
Pore spaces in the material are filled mainly with air
Zone of saturation
All pore spaces in the material are filled with water
Water within the pores is groundwater
Water table – the upper limit of the zone of saturation

6. Porosity vs Permeability
Amount of pore space available
Determines how much groundwater can be stored
Depends on:
Shape, packing and arrangement of grains
Well-sorted: all grains are the same size (high porosity), examples: sand, poorly cemented coquina.
Poorly-sorted: finer grains fill spaces between larger grains (low porosity), examples: well-cemented sandstone, shale, mudstone, and limestone.

7. Porosity vs Permeability
Ability to transmit water through connected pore spaces
How easily water can flow through a rock or sediment
Depends on:
Grain size (Coarser-grained sediments are more permeable than fine-grained sediments because the pores between the grains are larger)
Grain shape and packing (sorting)

8. Groundwater Features Wells Artesian wells
Pumping can cause a drawdown (lowering) of the water table
Pumping can form a cone of depression in the water table
Artesian wells
Water in the well rises higher than the initial groundwater level

9. Formation of a Cone of Depression

10. Aquifers
Aquitard – formed by impermeable materials that create a zone of saturation above it
Aquifer – permeable layers that allow water to flow freely through
The source of most water wells

11. Two Types of Aquifers
Unconfined: water level rises freely as the aquifer recharges
Confined: rising water reaches impermeable layer, becomes pressurized
Use aquifer coloring sheet for pictures

12. Groundwater Overuse Groundwater is replenished mostly by rain
If there is less rain than use of the water, the water level will decrease

13. Groundwater Overuse
Cone of depression – lowering of the water table around a well due to large amounts of water being pumped out

14. Groundwater Overuse
Ground subsidence (sinking) can occur if water is used faster than it is replenished
Creates depressions or sinkholes

15. Sources of Groundwater Contamination
Sewage from septic tanks, farm wastes, inadequate or broken sewers
Fertilizers and pesticides from agriculture
Residential runoff
Highway salts
Chemical and industrial materials that leak from pipelines, storage tanks, landfills, or holding tanks
Saltwater in coastal areas
Minerals and nutrients from dissolved rock and other natural materials

17. Groundwater Pollution
Point Source Pollution – contaminants have an identifiable source
Smokestacks, car tailpipe
Nonpoint Source Pollution – contaminant source cannot be found
Several farmlands in the same area
Flow downhill – contaminants leaked into the ground at the top of a hill will flow downhill
Rainwater – runs through the contaminant, absorbs it, and transfers it to another area

18. Groundwater Cleaning
If water travels slowly through sand or permeable sandstone, the water is purified
Sometimes contaminated water is pumped out of an aquifer and treated; the aquifer is replenished naturally or with the treated water

19. River Basins
Encompasses all the land surface that drains surface water from many finger-like streams and creeks which flow downhill into one another and eventually into one large river which takes the water to the ocean.

20. River Basins
Watersheds (river basins) are separated from each other by areas of higher elevation (ridge lines/divides).
Water channels at ridge lines will be narrow with fast-moving water.
As channels combine, the width of the stream will increase.
Watersheds have a branching appearance due to the tributaries (small streams branching from larger streams and rivers)

21. NC River Basins

22. Wetlands Land that is covered by water all or part of the year.
Includes swamps, marshes and bogs

23. Wetlands 3 Functions: Provide flood protection during storms
Filter pollution and urban runoff
Habitat for many animals

24. Wetlands Swamp Mostly trees and bushes Marsh
Tall grasses, some trees and bushes
Carolina Bays
Unique to East Coast
Oval-shaped lakes that often fill with plants and sediment