UNIT 8 EARTHS FRESH WATER

How much water do we use? 140 billion gallons daily in the United States alone Expected to grow

Water takes up 70% of our Earth! 97.2 % Salt Water 2.2 % Glaciers/Icecaps 0.6 % Surface/Underground 0.01 % Rivers/Lakes/Streams % Atmosphere

Red Book Pg. 361

Of the Fresh Water 76% Ice 12% Shallow Groundwater 11% Deep Groundwater.34% Lakes and Rivers.037% Water Vapor

Red Book Pg. 361

This leaves 15% of our fresh water available for use..42% of all water on Earth Why don’t we run out of water?

The Water Cycle  The continuous process by which water moves throughout the environment

The Water Cycle  From oceans and freshwater supplies to the air, land and back to the oceans

3 Steps to the Water Cycle  Evaporation  Condensation  Precipitation The Water Cycle

Evaporation/Transpiration  When water changes to vapor or gas The Water Cycle

Condensation  When vapor turns to liquid The Water Cycle

Precipitation Water returns to the Earth The Water Cycle  Rain, snow, sleet or hail

How do people use water?  Agriculture - Irrigation for farming  Industry - Uses water to produce objects

Uses (cont.)  Transportation - People and goods  Recreation - Swimming, boating, etc. Fresh Water Usage Handout!

Water Usage Lab  Fill out chart on back of lab sheet  List 10 other ways to conserve water (#3)  In your lab report explain how much water you could save and how you are planning to do it.  Hint: Use data from chart.

Water Cycle Quiz

5&6. Describe 2 of the 4 steps in the water cycle. 7. In your own words, describe the water cycle. 8. Explain why there are water shortages if the earth's total water volume is constant.

Water Cycle Bonus

 Running water  Standing water 2 Types of fresh water on the surface

Running Water  Surface runoff - Water that enters a river after a heavy downfall  Watershed - Area where runoff drains into the river system

Watersheds

Standing Water  Lakes and ponds - depends on size  Reservoirs - Artificial lake built by damming a stream or river

Quabbin Reservoir  Construction  412 billion gallons flooded the Swift River valley  Largest man-made reservoir in the world

Quabbin Reservoir (cont.)  Floods left Prescott, Enfield, and Greenwich under water.

Blue Hills Reservoir  Constructed in the early 1950s  Provided storage until 1981  Removed due to water quality.

MA Watersheds

What is Groundwater?  Water that remains in the ground The Water Cycle

Water beneath the Surface  Ground- water seeps between pores in the soil

Permeable vs. Impermeable  Permeability -The ability of material to let water pass through it

Permeable or Impermeable? Impermeable Permeable

Underground Zones  Zone of saturation  Zone of aeration  Water table  Aquifer  Artesian well

Zone of Saturation  Underground area where all pores are filled with water

Zone of Aeration (Unsaturated Zone)  Dry region where the pores are filled mostly with air

Water table  Area including the zone of saturation and zone of aeration soaked with water

How do we bring groundwater to the surface?  Wells - Drill a hole below the water table and pump water to the surface

Aquifers  Layer of permeable rocks that allows the water to flow sideways between impermeable layers  Sandstone, gravel, sand

Aquifers

Artesian well

 Well water that flows on its own without pumping

QUIZ

Solute Solvent Polar molecule Water as a universal solvent Acid Base pH Ecology Book

The substance that dissolves in a solution Solute Solvent The liquid in which the solute dissolves

A molecule that has a negative charge at one end and a positive charge at the other Polar Molecule

Solution with more hydrogen ions than hydroxide ions Acid Base Solution with more hydroxide than hydrogen ions

Units by which acids and bases are measured pH less than 7 = Acid pH greater than 7 = Base pH

Resists changes in temperature Universal solvent Polar molecule Neutral pH Importance of Water

How do we make water drinkable?

Public and private water supplies often need treatment to improve water quality  Measurement of substances in water besides molecules Read from Red Book pg

Water Quality  Appearance and taste  Acidity (pH)  Hardness u Hard water does not mix well with soap  Disease  Health Standards

Water Quality 1. First Filtration - Screens 2. Coagulation - Alum added 3. Second Filtration 4. Chlorination - Cl added 5. Aeration - Releases gasses 6. Additional treatment - Fluoride

Treating Wastewater 1. Primary treatment  Water slows down particles fall out 2. Secondary treatment  Filtered through gravel & bacteria 3. Additional treatment  Chlorine added