1. WATER
Humans can survive a month without food, but will only live a few days without water
Fresh water ~ water that people can drink
Salt water ~ water in the ocean
Water can be found as a solid, liquid, or gas
Water is a renewable resource that is constantly being circulated

2. The Water Cycle CONDENSATION EVAPORATION PRECIPITATION RUNOFF
PERCOLATION
CONDENSATION

3. 3% fresh water 1%
22%
77%
97% salt water

4. Where is the water? Surface water = fresh water on the Earth’s surface
River systems
water from rain and melting snow runs off from mountains, hills and other high places
the water runs into streams
many streams combine to form rivers
The Mississippi, Amazon, and Nile are enormous river systems

5. Mississippi River and its tributaries
Gulf of Mexico

6. Groundwater
Groundwater is water beneath the Earth’s surface in soil and rock formations.
Aquifer is an underground formation that contains groundwater
Water table is the level where rocks and soil are saturated (filled up) with water
The water table can be just below the surface or hundred’s of feet below ground

7. How caN THERE BE WATER IN ROCK?
Porosity: The percentage of the total volume of rock or soil that has spaces (pores)
In an aquifer, the groundwater occupies the pores
The higher the porosity, the more groundwater rock or soil can hold
The soil is called saturated when the pores are holding as much water as possible

8. How does the water get into the rock?
Permeability = The ability of rock or soil to allow water to flow through it
Materials that allow water to flow are permeable
Materials that do not allow water to flow are impermeable
Water on the surface percolates through the ground and ends up in the pore spaces as groundwater

9. What is a drinking Water Well?
Aquifer recharges as water percolates through the overlying soil to reach the aquifer
aquifer