Water Quality

Question 1

Water Percentage

Answer 1

• 60% (2/3) of body is water
• 75% (3/4) of brain tissue
• Humans survive without food or water
  
  • Approx 30 days without food
  • Approx 1 week without water
• Humans need 2.5 liters a day

Question 2

How much water

Answer 2

• 71% of earth’s surface is covered in water
  
  • 97% is salty
  • 3% is fresh
  • 60% of fresh water is locked in the Artic
  • 1% is unavailable

Question 3

Water Cycle

Answer 3

Process where freshwater supply is continuosly replinished

(1) Driven by sun
(2) Fresh H20 from the ocean, forms cloud
(3) Deposits on land
(4) Returns to the ocean

Question 4

Water sources

Answer 4

• Surface water
  
  • All naturally open to atmosphere (rivers, lakes, and reserviors
• Ground water
  
  • fresh water under the ground
• Aquifer
  
  • need recharging
  • gradually being depleted

Question 5

How we use water

Answer 5

• 50% landscaping
• 14% toilets
• 12% laundry
• 9% showers
• 8% faucets
• 5% leaks
• 1% baths and dishwashing

Question 6

Water Scacity

Answer 6

• Water scarcity: when water renewal is <1,000 M3/per person
• Water stress: when renwal of water is between 1,000 to 1,700 M3/person

Question 7

Water Conservation

Answer 7

• Technical changes
  
  • Micro-irrigation
    
    • Transports via pipes istead of ditches
  • Xeriscaping- use native plants i.e., desert plants
• Social changes
  
  • Water use and conversation

Question 8

Water Conservation

Answer 8

• Desalination: separation of water and salt
  
  • Too Expensive
  • Nowhere to put salt disposal
• Dams and reserviors
  
  • Benefits and costs
• Canals or aqueducts

Question 9

Water Conservation

Answer 9

• Farmers use 85% of available water
• Solution
  
  • Grow high price non water intensive crops
    
    • Nuts and vegetable vs. rice
  • Water intensive crops can be grown elsewhere

Question 10

Water Treatment

Answer 10

• Screen:
• Coagulation: removes dirt and other particles suspended in water. Chemicals are added to water to form sticky particles called “floc” which attracts dirt particles.
• Sedimentation: Combined weight causes floc to sink to the bottom.
• Filtration: Water passes through filters, made of layers of sand, gravel, and charcoal that help remove smaller particles.
• Disinfection: Small amount of chlorine is added to kill any bacteria or microorganisms that may be in the water.

Question 11

Water Contamination

Answer 11

• Chemical
  
  • Naturally occuring- Nitrate, flouride, arsenic
  • Manmade- oil spills
• Microbiological
  
  • Cyano bacteria, blue green (algae bloom)
  • releases neurotoxins, hepatotoxins
• Vector
• Bottled water

Question 12

Diseases

Answer 12

• Water borne disease and fecal contamination
  
  • E. Coli used as a marker
• Chlorination drastically reduced waterborne infections in the U.S
  
  • Cholera and typhoid
• Contaminants
  
  • Protozoa- cryptosporidium
  • Bacteria- E. Coli
  • Viral- Norovirus