Freshwater

6th Grade Science

I. Supply and DemandA. Types of Use

1. Home2. Industry3. Transportation4. Agriculture - Irrigation5. Recreation

I. Supply and DemandB. Amount

1. Average U.S. = 340 Liters per dayC. Conservation

1. Reducei. Shower: 18 liters per minuteii. Paper: 227 liters water per kg

paper (cut ½)iii. Drip lines

2. Reusei. Sink water for plants…

D. Producing1. Desalination (expensive)2. Icebergs (Weather)

II. Water to Drink A. Quality

1. Acidity (6.5 to 8.5)i. Acid ruins pipes

2. Hardness (mineral in water)i. Prevents soap formationii. Leaves behind deposits

3. Organisms (bacteria)

B. Treating Water1. Filtration = Remove large particles in water

(screen)2. Coagulation = Add sticky particles to filter pieces3. Chlorination = Kill living things4. Aeration = Removes odors and tastes5. Testing = Make sure quality

C. Wastewater1. Waste treatment plant2. Septic System

III. PollutionA. Where

1. Point Source = Known spot of entry into water

2. Nonpoint Source = Widespread entry3. Effects = Pesticides

III. PollutionB. Human Wastes

1. Sewagei. Citiesii. Rural Areas

2. Industriali. Chemicalsii. Smokeiii. Heat

III. PollutionC. Chemical Run-off

1. Farmsi. Fertilizers - Aid growth of algae

(use up O2)

ii. Pesticides – Kill animals downstream2. Roads

i. Spills – Gasoline, oilii. Treatments – Salting roads

D. Solutions

IV. AmountsA. Droughts

1. Long periods without rain

B. Flood1. Water overflows banks2. Flash Floods

C. Flood Precautions

V. Water PowerA. Energy

1. Kinetic Energy – Moving Energy2. Potential Energy – Stored Energy for

future use

B. Hydroelectric Power (9% in U.S.)1. Convert kinetic energy to electrical

energy2. Advantage – Clean, Safe, Renewable3. Disadvantage – Expensive, Dramatic

change in life