Warm-upWhat do you know about water?

Lesson Essential QuestionWhy is water important?

InteractionGW and SW, not isolated components of hydrologic system

Interact in variety of physiographic and climatic landscapes

InteractionDevelopment or contamination of one directly affects the other

Why??

ScarcityWater essential for all socio-economic development & for maintaining healthy ecosystems

As population , need for waterMay lead to conflict, tensions, etc

Scarcity•Water scarcity- point at which the aggregate impact of all users impinges on the supply or quality of water under prevailing institutional arrangements to the extent that the demand by all sectors…cannot be satisfied.

ScarcitySymptoms- severe environmental degradation

EX??Declining groundwater levels

Problems of water allocation

Scarcity1.2 billion people, live in areas of physical scarcity

500 million approaching situation

1.6 billion face water shortage

ReadingsEach student reads an article, pick out important information, tell the class what your article was about and why this is important.

Warm-upWhy is water important?

Lesson Essential QuestionWhat is the relationship between bodies of water and civilization?

Water and CivilizationEX: Mesopotamian-> Tigris and Euphrates River

Egypt-> Dessert but Nile flood

Minoan-> Island of CreteWhy?

Water and CivilizationWater needed for fertile soil

Farm and CropsAll living things need water to survive

Catalyst for growth

Water CycleImportance- pollution of one source affects whole cycle

Draw water cycle and explain importance of each part as it relates to the environment – 20 minutes

Water PropertiesGas becomes solid through frost formation

Solid melts to become liquid

Liquid evaporates into gases

Water PropertiesAffect on ecosystem: Liquid- allows organic compounds to react, needed for all life, if floods, could destroy ecosystems, cause contamination

Water PropertiesAffect on ecosystem: Solid-freezing kills pests, affects vitality of fine tree roots, slows decomposition, accelerates movement of Nitrogen from fresh litter

Water PropertiesAffect on ecosystem: Gas- humidity, good for plant life

Water TestingStudents take samples from stream

Test in classroomContaminated or not?

Warm-upWhy is periodically testing your water important?

Lesson Essential QuestionHow does water use get divided up?

Water Use Planning•Dams, Reservoirs and ponds•2 uses– reduce flooding hazard, water collected and stored •Other uses- recreation, supply water to town/city, water to industry, irrigation to farms, power

Water Use PlanningDams, reservoirs and pondsDisadvantages- expense, flood control- levels need to be lowered before rainy season so no flooding occurs

Water Use Planning•Waterway use•Power required to move goods on water is less than that required to move on land•Maintenance costs on ships are less than on rail, truck or air equipment

Water Use PlanningWaterway useMost common water-transported items- petroleum and coal products

Water Use PlanningWaterway useWWII, merchant ships used intracoastal waterway to avoid German submarines

Desalination70% of earths surface- oceans

Can we use it if freshwater supplies lessen?

Desalination•Yes, after following steps•1st- must remove salt•Desalination- the process of salt extraction•Not new, been around for centuries

Desalination•2 techniques •1.Membrane process- the filtering of salt from water through a series of filters–Used on brackish water where the salt content is lower–2 types

DesalinationA. Reverse Osmosis- uses natural principles of liquids flowing through a semipermeable membrane

Video

Desalination•B. Electrodialysis- uses fact that ocean water contains sodium and chlorine•Two elements separate when electric current used, they separate & pass through different filters

DesalinationElectrodialysis- freshwater is left over and pumped away

Uses a lot of electric power and expensive filters

Desalination•2. Distillation process of desalination•Nature uses in hydrologic cycle•When water heater, it evaporates & leaves solid impurities. You collect & condense vapor= fresh water!

2. Distillation process of desalination1. long-tube distillation- saltwater sent through tubes, heated with stem.

Vapor travels through tubes where it is cooled and collected

2. Distillation process of desalination1. long-tube distillation- conserves energy and lowers cost of distillation

2. Distillation process of desalination•2. Vapor compression distillation- place water under pressure when turned into steam, steam heats other waters, steam condenses and falls to a bottom tank, then collected

2. Distillation process of desalination2. Vapor compression distillation- energy used to start process and run compressor motor

2. Distillation process of desalination3. Flash distillation- heating water and allowing it to flow into a chamber. Partial vacuum produced, water immediately boil or “flash” into steam. Steam cooled and collected

2. Distillation process of desalination3. Flash distillation- steam cooled by incoming saltwater, requires less heat energy to cause it to flash

2. Distillation process of desalination44% of worlds desalinization capacity through flash distillation in 1999

40% from reverse osmosis

2. Distillation process of desalination1945- 1 plant producing 326 cubic meters per day

2004- 10,000 plants capable of producing 35 million cubic meters per day

ActivityWho owns water? Lab.

Warm-upWhat type of desalination is this?

Lesson Essential QuestionWho is the most intensive user of water? Why?

Use of water

•Typical person:–50-75 gallons a day–40% flushing toilets–30% bathing–20% laundry and dishes–5% drinking–5% other

Use of waterMost intensive users are agriculture and industry

Weather Control Water UseSkiing? No snow? No BIG DEAL!

Why?!?!

Weather Control to provide water

Making rain- seed clouds with silver iodide crystals (sometimes dry ice). Crystals give water droplets something to cling to.

As droplets form, become heavy & fall to earth as rain

Weather Control to provide water

Problems? Only increases rainfall by 20%!

May not fall where neededTakes rain from other places

Weather ControlOther uses?Modification of tornados & hurricanes- silver iodide to lower winds

Transporting Water for useReal problem w/water? NOT ENOUGH! Water not where people are.

Transporting WaterAncient Romans engineers created aqueducts to transport water through Empire.

Rome- 11 aqueducts- 260 miles constructed over 5 centuries

29 miles above ground, rest underground tunnels

Transporting WaterMid 1800s- The Salt River Project provided water for Greater Phoenix, Arizona for over century

Los Angeles Aqueduct- 1913, $23 million, 223 miles, 98 miles concrete conduit & 52 miles in tunnels, 37 miles lined canals

Transporting Water2nd LAA- 1970, $89 million, 137 miles, 64 miles concrete & 69 miles steel pipeline

1st- move 485 cubic feet per second

2nd- move 290 cubic feet per second

Water Runoff control in Urban Areas1 inch rain dumps 43,560 gallons water per acre

Most water runs off, gutters & sewers transport to streams or rivers, sometimes causes flooding

Cities should collect water runoff for when water will be short

Water ConservationQuality of water? Should reserve top quality water for drinking or cooking

One proposal- re use all water, even sewage water

How does that make you feel? Why?

Water ConservationFederal government placing tighter pollution standards on industrial water supplies.

Water ConservationWater: An Amazing and Precious Resource Activity

Review for test