Chapter 151. Summarize the water problems throughout the world: Water distribution is

low and requires a combination of regional cooperation of allocating water supplies, slowed population growth, efficiency in water usage, higher water prices, improved irrigation, and increased grain imports

2. Explain why there is a danger of water wars: Some countries or cities will build dams that block water paths for other people (Ethiopia, Sudan, Egypt – Ethiopia and Sudan block water ways to Egypt. Egypt can start war)

3. How much of the earth’s surface is covered by water? 71%4. What percent of the earth’s water is saltwater? 97.4% Freshwater? 2.6%

readily accessible fresh water? 0.014%5. Where is the freshwater? Glaciers, ice caps, groundwaters, lakes, biota, rivers,

atmospheric water vapor, soil moisture6. Say something intelligent about the properties of water [hydrogen bonds,

heat capacity, UV, freezing]: a. There are strong forces of attraction (Hydrogen bonds) between

molecules of waterb. Water exists as a liquid over a wide temperature range because of the

strong forces of attraction between water molecules [high boiling point]

c. Liquid water changes temperature slowly because it can store a large amount of heat without a large change in temperature and moderates the earth’s climate [large heat capacity]

d. Evaporating liquid water takes large amounts of energy because of the strong forces of attraction [heat distribution and determine climate]

e. Liquid water can dissolve into a variety of compound [carry dissolved nutrients, flush waste, all purpose cleaner, rove and dilute water-soluble wastes]

f. Water filters out wavelengths of the sun’s UV radiation that would harm aquatic organisms

g. Cohesive force capillary actionh. Water expands [ice has low density]

7. Water – saturated layers of porous underground rock are known as groundwater.

8. What is the water table? The water table is located at the top of the zone of saturation.

9. What happens to the water table during dry weather? Water table falls, and rises in wet weather

10. Distinguish the following:a. Surface runoff: the precipitation that does not infiltrate the ground, or

evaporateb. Reliable runoff: Remaining 1/3 run off that we can use as stable

source of waterc. Watershed/Drainage Basin: The region from which surface water

drains into a river, lake, wetland, or other body of waterd. Groundwater: The water stuck under porous soil and rock

i. Ground water normally moves from points of high elevation and pressure to points of lower elevation and pressure: slow movement

ii. Groundwater recharges slowlye. Zone of aeration/Zone of saturation/Water Table: Close to the surface

is the zone of aeration, the pores of soil contain a mixture of air and some water. Lower layers of soil where the spaces are completely filled with water make up the zone of saturation. We drill shallow wells to tape into groundwater in this zone. The water table is located at the top of the zone of saturation.

f. Aquifer: Deep down, porous, water-saturated layers of sand, gravel, bedrock through which groundwater flows

g. Natural recharge: Replenished by precipitation that percolates downward (gravity) through soil and rock

i. Lateral recharge: streams11. Explain how the water in some aquifers can be depleted: Use faster than

recharge, used up fossil aquifers that are nonrenewable, water mining12. Distinguish between water withdrawal and consumptive water use:

a. Water withdrawal: The total amount of water we remove from a river, lake, or aquifer for any purpose

i. May be put back but causes thermal pollutionb. Consumptive water use: Water withdrawn is not available for reuse in

the basin from which it was removed – due to evaporation, seepage underground, transported to another area, contamination

13. Throughout the world, the most water is used for agriculture. The greatest household use is for flushing toilets.

14. Irrigation is the biggest user of water (70%) followed by industries (20%) and cities and residences (10%)

15. Major water problems of the eastern United States include flooding, occasional urban shortages, and pollution.

16. Major water problems of the western United States include shortage of runoff, caused by low precipitation, high evaporation, and recurring prolonged drought.

17. Water scarcity during a period when precipitation is lower than normal and evaporation is higher than normal is called a drought.

18. We currently withdraw34% of the reliable surface runoff and in 2025 we will withdraw more than 70%.

19. List four causes of water scarcity:a. Dry climate, drought, desiccation (drying of exposed soil because of

deforestation and overgrazing), and water stress (low per capita availability of water)

b. A country is water stressed when the volume of reliable runoff per person drops below 1,700 cubic meters per year (water withdrawal 20% higher). A country suffers from water scarcity when per capita water availability falls below 1,000 cubic meters per year.

c. 41% of the world’s population lives in river basins located in 20 countries that suffer from water stress or water scarcity. 40 countries by 2020, 60 countries in 2050.

20. Identify ways that water supply can be increased (six ways):a. Build dams and reservoirsb. Bring in surface water from another areac. Withdraw groundwaterd. Convert salt water to freshwater (desalination)e. Reduce water wastef. Import food to reduce water useg. Raising livestock

21. Discuss the controversy over whether freshwater resources should be owned and managed by governments or by private corporations:

a. Private companies have the money and expertise to manage these resources better than government bureaucracies

b. Governments hiring private companies to manage water resources must set standards and maintain strict oversight of such contracts

c. Water is a public resourced. Once water is owned by foreign-based corporation, efforts to return

the systems to public control can lead to severe economic penalties under World Trade Organization

e. Private companies make money by delivering water, and have more incentive to sell as much water than conserve

f. Lack of money to pay water bills, the poor will be left out22. Dams

a. Pros:i. Reservoir is useful for recreation and fishing

ii. Can produce cheap electricityiii. Downstream flooding is reducediv. Provides water for year-round irrigation

b. Cons:i. Large losses of water through evaporation

ii. Flooded land destroys forests or cropland and displaces peopleiii. Migration and spawning of some fish are disruptediv. Downstream cropland and estuaries are deprived of nutrient-

rich siltc. The more large dams built, the more annual reliable runoff increased

for humans. However it can reduce downstream flow to a trickle and prevent it from reaching the sea as a part of the hydrologic cycle.

d. Colorado River Basin – Las Vegas (Nevada), San Diego (California), Imperial Valley (California), Mexico

i. Pros:1. Provides hydroelectricity plants2. Water for more than 25 million people in 7 states3. Water used to grow about 15% of the nation’s produce

and livestock

4. Supports a multibillion-dollar recreation industryii. Cons:

1. Includes driest lands in the United States and Mexico2. Legal pacts in 1922 and 1944 allocated more water for

human use than the river can supply3. Pact also allocated no water for environmental

purposes4. Withdrawals of water prevented river to go to Gulf of

California which threatens the survival of species that spawn in the river

e. China’s Three Gorges Dami. Pros:

1. Will generate about 10% of electricity2. Reduce dependence on coal3. Reduces air pollution4. Reduces CO2 emissions5. Reduces chances of downstream flooding for 15 million

people6. Reduces river silting below dam by eroded soil7. Increases irrigation water for croplands

ii. Cons:1. Floods large areas of croplands2. Displaces 1.9 million people3. Increases water pollution because of reduced water

flow4. Reduces deposits of nutrient-rich sediments below the

dam5. Increases saltwater introduced into drinking water near

mouth of river because of decreased water flow6. Disrupts spawning and migration of fish 7. High cost

23. How do dams relate to…a. Soil Fertility: Downstream croplands are deprived of siltb. Air Pollution: Generates electricity, reduces need for energy by coal,

reduces air pollutionc. Flooding: Downstream flooding is reduced, but will flood lands and

displace people upstreamd. Farming: Regulates irrigation for cropland, but prevents silt to run

downstream24. Describe the cause and effects of the Aral Sea water transfer project in

central Asia: It is a result of a large-scale water transfer project in an area of the former Soviet Union with the driest climate in central Asia. The water transfer was used to create irrigated areas for cotton and rice. This projected, coupled with droughts and high evaporation rates has caused a regional ecological, economic, and health disaster. The sea’s salinity has tripled.

25. Describe the controversy over:

a. California Water Transfer Projecti. Sending more water south would degrade the Sacramento

River, threaten fisheries, and reduce the flushing action that helps clean San Francisco Bay of pollutants.

b. James Bay Water Transfer Projecti. Flood an area of boreal forests and tundra. It will displace

thousands of indigenous Cree and Inuit, who have lived off of James Bay by subsistence hunting, fishing, and trapping.

26. List the advantages and disadvantages of supplying more water by withdrawing groundwater. Explain why excessive groundwater withdrawal can be viewed as an example of the tragedy of the commons. What is saltwater intrusion, where does it occur, and what harm does it cause?

a. Pros:i. Aquifers are widely available and are renewable sources of

water as long as the water is not withdrawn faster than it is replaced and as long as the aquifers aren’t contaminated

b. Cons:i. Water tables are falling in many areas, groundwater is being

drawn more than its replacement rate, and urban development cover aquifer recharge areas

1. Withdrawing lots of water sometimes allow the sand and rock in aquifers to collapse, causing the land above the aquifer to subside or sink. Once an aquifer becomes compressed, recharge is impossible. Excessive withdrawal of groundwater can cause the roof of a cavern or underground conduit to collapse and create a large crater (sinkholes). Finally, groundwater overdrafts near coastal areas can contaminate groundwater supplies by causing intrusion of salt water into freshwater aquifers used to supply water for irrigation and domestic purposes.

27. Summarize the advantage and disadvantage of withdrawing groundwater from the Ogallala Aquifer (largest aquifer, overdraft) in the United States:

a. Pros:i. Pumping large amounts of water from this fossil aquifer has

helped to transform vast areas of arid high plains into a highly productive agricultural region.

b. Cons:i. This aquifer is over pumped and it is gradually depleting. It has

a slow recharge rate, and people are pumping faster than it recharges.

28. List nine ways to prevent or slow groundwater depletiona. Prevent

i. Waste less waterii. Subsidize water conservation

iii. Ban new wells in aquifers near surface waters

iv. Buy and retire groundwater withdrawal rights in critical areasv. Do not grow water-intensive crops in dry areas

vi. Reduce birth ratesb. Control/Slow

i. Raise price of water to discourage wasteii. Tax water pumped from wells near surface waters

iii. Set and enforce minimum stream flow levels29. What are two concerns about withdrawing water from huge, very deep

aquifers?a. One is that we know little about the geological and ecological impacts

of pumping from deep aquifers. The other is that no international water treaties govern the rights to and ownership of water that underlies several countries.

30. What are the problems associated with desalinization. List the advantages and disadvantages of increasing supplies of fresh water by desalinization of salt water.

a. Two methods in desalinating water: Distillation (heating salt water until it evaporates), Reverse osmosis (pumping salt water at high pressure through a thin membrane with pores that allow water molecules, but not dissolved salts, to pass through)

b. Pros:i. Provides more water to water short areas

c. Cons:i. High cost because it takes a lot of energy to desalinate water

ii. Desalination produces large quantities of briny waste water that contains lots of salt and other minerals

31. How useful are cloud seeding and iceberg towing to increase water supplies?a. Cloud seeding

i. Does not work well in dry areas where rain is needed most because there are few clouds to seed

ii. Technology may not workiii. Introduces large amounts of cloud-seeding chemicalsiv. Seeding has led to legal disputes

b. Iceberg Towingi. Cost too much

32. We waste about 2/3 of the water we use but using water more efficiently could reduce wastage to about 15%

a. Why we waste wateri. We charge little for water subsidies keep price so low that

users have no incentive to save waterii. Lack of government subsidies for improving the efficiency of

water use33. Describe three major irrigation systems and liste them in order of their

efficiency of water usea. Drip irrigation/microirrigation system plastic tubing installed at or

below ground level

b. Center pivot low-pressure sprinkler uses pumps to spray water on crops

c. Low energy precision application sprinkler center pivot irrigationd. Surge valves time controlled, gravity flow irrigation ditches in

pulsese. DriWater 1-liter gel-encased water that releases slowly

34. How can irrigation systems lose watera. Water is delivered far more than the crops need and lose water

through evaporation, seepage, runoff35. List nine ways to reduce water waste in irrigation and eleven ways to reduce

water waste in industry, homes, and businessesa. Nine ways

i. Lining canals bring water to irrigation ditchesii. Leveling fields with lasers

iii. Irrigating at night to reduce evaporationiv. Using soil and satellite sensors and computer systems to

monitor soil moisture and add water only when necessaryv. Polyculture

vi. Organic farmingvii. Growing water-efficient crops using drought-resistant and salt-

tolerant crop varietiesviii. Irrigating with treated urban waste water

ix. Imported water-intensive crops and meatb. Eleven ways

i. Redesign manufacturing processesii. Landscape yards with plants that require little water

(xeriscaping)iii. Use drip irrigationiv. Fix water leaksv. Use water meters and charge for all municipal water use

vi. Raise water pricesvii. Use waterless composting toilets

viii. Require water conservation in water-short citiesix. Use water-saving toilets, showerheads, and frontloading

clothes washersx. Collect and reuse household water to irrigate lawns and

nonedible plants (gray water)xi. Purify and reuse water for houses, apartments, and office

buildings36. List five principles for reducing the use of water to remove industrial and

household wastesa. Use pollution prevention and waste reduction to sharply decrease the

amount of industrial wastes we produceb. Ban discharge of industrial toxic wastes into municipal sewer systems

c. Rely more on waterless composting toilets that convert human fecal matter to a small amount of dry and odorless soil-like humus material that can be removed from composting chamber every year.

d. Returns the nutrient-rich sludge produced by conventional waste treatment plants to the soil as fertilizer

e. Shift to new ways to treat sewage that mimics the way nature breaks down and recycles nutrients

37. Floodplainsa. Fertile soil, ample water for irrigation, availability of nearby rivers for

transportation and recreation, flat land for suitable cropping, buildings, high ways, and railroads

b. People deliberately settle on floodplains then expect dams, levees, and other devices to protect them from floodwaters.

38. List the major benefits and disadvantages of floods. List four ways in which humans increase the damages from floods.

a. Pros:i. Provide productive farmland, regularly covered with silt after

floodwater recedeii. Recharge groundwater

iii. Refill wetlandsb. Cons:

i. Kills people and cause tens of billions of dollars in property damage

c. Four waysi. Removal of water-absorbing vegetation

ii. Draining wetlands that absorb flood watersiii. Living on floodplainsiv. Pave or build and replace water-absorbing vegetation with

highways, parking lots, buildings39. Bangladesh’s Floodplain problem

a. Increased flood problems begin the Himalayan watershed, where several factors – rapid population growth, deforestation, overgrazing, and unsustainable farming on steep and easily erodible mountain slopes- have greatly diminished the ability of its mountain soils to absorb water.

b. Cut down forests that absorb and slowly release water increases the runoff of soil, heaver monosoon rains.

40. Reduce risk of flooda. Think carefully were to liveb. Identify and mange flood-prone areasc. Prevention

41. Sustainable water usagea. Not depleting aquifersb. Preserving water qualityc. Raising water pricesd. Wasting less water

e. Slowing population growthf. Decrease government subsidiesg. Marketing of water rights

42. Deforestation decreases evaporation. Increases flooding. Decreases diversity. Decreases nutrients in soil. Increases spawning areas.

43. Mulch is helpful waste or fertilizer and helps for agriculture.

Chapter 221. Describe John Todd’s living machines used to purify sewage. What are the

steps? How is the water made pure enough to drink?a. Sewage flows into a passive solar greenhouse First tank: algae and

microorganisms decompose organic wastes, with sunlight speeding up the process. Water hyacinths, cattails, bulrushes, and other aquatic plants growing in the tanks take up resulting nutrients Second tank: Artificial marsh of sand, gravel, and bulrush plants to filter out algae and remaining organic wastes. Some of these plants absorb sequester toxic metals such as lead and mercury and secrete natural antibiotic compounds that kill pathogens Third step: water flows into aquarium tanks. Snails and zooplankton in these tanks consume microorganisms and are in turn consumed by crayfish, tilapia, and other fish that can be eaten or sold as bait. After 10 days, the clear water flows into a second artificial marsh for final filtering and cleansing Lastly, the water is made pure by exposing it to UV light or passing it through an ozone generator.

2. What is water pollution? What are eight types of water pollutants, and what are the major sources and effects of each type?

a. Infections Agents1. Examples: Bacteria, viruses, protozoa, parasitic worms

ii. Major Human Sources:1. Human and animal waste

iii. Effects1. Diseases

b. Oxygen – Demanding Wastes1. Organic wastes

ii. Sewage, feedlots, paper millsiii. Large populations of bacteria

c. Inorganic Chemicals1. Water soluble acids, compounds of toxic metals such as

lead, arsenic, and selenium, salts such as sodium chloride in ocean water and fluoride

ii. Surface Runoff, industrial effluents, household cleanersiii. Can make freshwater unusable, skin cancers, damage to neck

and liver system, harm fish, lower crop yieldd. Organic Chemicals

1. Oil, gasoline, plastics, pesticides, cleaning, solvents, detergents

ii. Industrial effluents, household cleaners, surface runoff from farms and yards

iii. Threaten human health, threaten fishe. Plant nutrients

1. Water soluble compounds containing nitrate and phosphate and ammonia

ii. Sewage, manure, and urban fertilizeriii. Can cause excessive algae growth, eutrophication

f. Sediment1. Soil, silt

ii. Land Erosioniii. Can cloud water and reduce photosynthesis, disrupt aquatic

food webs, carry pesticides, destroy feeding spawning grounds, clog and fill lakes, eutrophication

g. Radioactive materials1. Radioactive isotopes of iodine, radon, uranium, cesium,

thoriumii. Nuclear and coal burning, mining

iii. Genetic mutations, miscarriagesh. Heat pollution (electric powerplants)

1. Excessive heatii. Water cooling of power plants

iii. Lowers dissolved oxygen levels and makes aquatic organisms vulnerable to diseases, lowers dissolved oxygen levels

3. Describe how a coliform bacteria count, measurement of dissolved oxygen, and biological indicators can be used to determine control? Why?

a. Fecal coliform bacteria: measure the colonies and can measure water quality

i. 100 milliliters for drinking and no colonies. 200 colonies, 100 milliliters for swimming.

b. Dissolved oxygen: measure by oxygen – demanding waste amountc. Indicator species: measure by removing aquatic plants such as cattails

to analyze the surrounding pollution. Mussels that feed by filtering water can analyze their body and determine water quality

4. The most commonly used herbicide can lead to developmental problems is Atrazine.

5. Associated with Minamata Bay, dancing cat syndrome, and coal burning power plants: Methyl mercury.

6. Water soluble gasoline additive that is a carcinogen: MTBE7. Point sources:

a. Drain pipes, ditches, sewer lines, factories, treatment plants, underground mines, oil tankers

8. Non point sources:a. Acid deposition, runoff, feedlots, logged forests, urban streets, lawns,

golf courses

9. Agricultural activities are by far the leading cause of water pollution, along with industrial facilities. Mining is the third source.

10. In a flowing stream, the breakdown of degradable wastes by bacteria depletes dissolved oxygen and creates an oxygen sag curve. This reduces organisms.

a. Depends on volume, flow rate, temperature, ph level11. Eutrophication:

a. Cultural eutrophication: urban or agricultural areas, human activities can greatly accelerate it (nitrate and phosphate containing effluents)

i. During a drought, nutrient overload produces “blooms: of organisms such as algae. This dense colony can reduce lake productivity and fish growth by decreasing solar energy for photosynthesis. When algae die their decomposition by swelling population of aerobic bacteria depletes dissolved oxygen in the surface layer. This oxygen depletion leads to fish kill.

12. Prevent, Reduce, Clean upa. Waste treatment systems, limiting the use of phosphates, reduce

nutrient run off, mechanically remove excess weeds, controlling undesirable plant growth, avoid oxygen depletion by pumping air

13. Preventing contamination is the most effective and cheapest way to protect groundwater sources

14. Parts of the world’s oceans are dump sites for a variety of toxic materials and sewage and garbage from ships

a. Dredge spoils – materials often laden with toxic metals scraped from the bottoms of harbors)

b. Sewage sludge – toxic chemicalsc. Most oil pollution is from land

15. Crude petroleum (oil from ground) v Refined petroleum (fuel oil)a. More damaging is refined, taking 10-15 yearsb. Crude is 3 years

16. Nonpolar molecules are more likely biomagnified. These molecules are fat soluble.

17. Organisms at higher tropic levels are most vulnerable to biomagnifications.18. Oxygen depleted zones (dead zones) are caused by excessive nonpoint inputs

of fertilizers and animal wastes from run offs and deposition of nitrogen compounds from the atmosphere

19. Treatment planta. Primary Sewage Treatment

i. Physical process: uses screens, grit tank (A) to remove large floating objects. Removes about 60% of the suspended solids and 30-40% of the oxygen demanding organic wastes. (B, settling tank, sludge)

b. Secondary Sewage Treatmenti. Biological process: aerobic bacteria remove 90% of dissolved

and bio-degradable, oxygen demanding organic wastes. This is

done by trickling waste water through beds of gravel covered with films of aerobic bacteria or by passing it through an aeration tank (C) where air is pumped through a slurry of aerobic bacteria (D, settling tank, sludge) (F, sludge digester) (G, sludge drying bed)

ii. Undergoes bleaching to remove water coloration, disinfection to kill disease-carrying bacteria chlorination (E, chlorine disinfection tank)

c. Advanced/Tertiary Sewage Treatmenti. Specialized chemical/physical process: Removes specific

pollutants left in the waterii. Ozone and UV light is used

d. Sludge is settled at the bottom, can be used as fertilizer or composte. Clean Water Actf.

20. Wastewater garden: removes most of fecal coliform bacteria and nitrates and phosphates. Water can be used to irrigate gardens, flush toilets