1. Water Resources

3. Where is our water?
* Water makes up 71% of our planet and 2/3 of our body
* One in every eight people lack access to clean fresh water
* Water is abundant globally, but water we can actually use is rare

4. Where is our water?

5. Water * Water is both a renewable and a limited resource
Renewable: The Water Cycle
Limited: Salt Water and Ice Caps

6. Water
The Hydrologic (Water) Cycle

7. Water
Per capita water resources

9. Water
* Many areas with a high population density do not live near water
* Some areas only receive rainwater during a certain season
Why do people chose to live there?

10. Surface Water
Surface water: easily accessible freshwater on the Earth's surface (~1% of all water)
i.e. ice caps, glaciers, rainfall, snow melt, lakes, ponds, rivers, streams
Runoff: water that flows over land and has not been absorbed into the ground

11. Surface Water
River system: a network of connected rivers and streams carrying water that flows downhill according to gravity
* Streams can flow into small rivers (tributaries) then into larger rivers, then eventually into a large body of water (lake or ocean)

12. Surface Water

13. Surface Water
Watershed: includes all of the land area that supplies water to a particular river system (a.k.a. drainage basin)

14. Surface Water

15. Surface Water
NY Watersheds

16. Ground Water groundwater: water found below the Earth's surface
zone of aeration: layer containing empty spaces (pores)
* water can pass through the zone of aeration making it a permeable layer
zone of saturation: layer in which pores are filled with water (saturated)
water table: boundary between the zone of aeration and the zone of saturation

17. Ground Water

18. Ground Water
* layers with few or no pores are called impermeable (water cannot flow through)
aquifer: sponge-like formations of rock, sand, or gravel that hold water
recharge zone: any area where surface water soaks into the ground and reaches an aquifer

19. Ground Water

20. Ground Water well: a hole dug into an aquifer to reach groundwater
artesian well: a hole dug to reach groundwater confined in an aquifer between two impermeable layers

21. Ground Water

22. Ground Water

23. Ground Water
Hydraulic Fracturing (Hydrofracking): a method used to harvest natural gas from shale (Marcellus and Utica shale)

24. Ground Water

26. Water Uses The three main ways humans use freshwater are:
* Agriculture (~70% globally)
* Industrial (~22% globally)
* Personal Use (~8% globally)
How much water does it take to......
fill the average swimming pool
19,000 gallons
water the average suburban lawn
750 gallons
take a 10 minute shower
40 gallons
flush the toilet
6 gallons
run a load of dishes in the dishwasher

27. Water Uses

28. Water Uses
77% of freshwater used in agriculture, industry and personal use comes from surface water (lakes, ponds, rivers, streams)
* Water has to be pulled from it's source then moved to where it will be used

29. Surface Water Uses
water diversion: moving water from it's source to where humans use it
* if agricultural, then it's called irrigation

30. Surface Water Uses
Dam: any obstruction placed in a river or stream to block its flow
* Dams create artificial reservoirs
Reservoir: large lakes that store water for human use

31. Water Uses

32. Water Uses

33. Water Uses

34. Water Uses

35. Water Uses

36. Water Uses

37. Water Uses

38. Surface Water Depletion
Drought and overuse leads to dried up rivers and lakes
The Aral Sea

39. Using Groundwater
In the US, 26% of all fresh water used is groundwater
* 68% of the groundwater is used for irrigation and is increasing
* most irrigation is inefficient, why?

40. Using Groundwater
waterlogging: saturating soil in a dry area with water to promote plant growth
salinization: the buildup of salts in the surface layers of soil

41. Using Groundwater
groundwater mining: withdrawing groundwater faster than it can be replaced
i.e.
Las Vegas and the
Great Basin

42. Using Groundwater
In Asia and in the Middle East, ground water is falling 3-10 ft. per year
* can cause salt water to move into aquifers
* surface above aquifers can subside

44. Solutions to Freshwater Depletion
Desalination: removal of salt from seawater, creating fresh water
Two ways:
* reverse osmosis (artificial membrane)
* evaporation (distillation)

45. Desalination

46. Desalination

47. Ways to reduce water use
Other ways to reduce demand:
Agriculture: drip irrigation
Industry: recycling water within the plant
Personal: water gardens/lawns at night, turn faucets off, switch to low-flow, fix leaky pipes
xeriscaping: use drought tolerant plants

48. Water Pollution
Point source pollution: comes from distinct locations, such as a factory or sewer pipe (you can see it enter the water)

49. Water Pollution
Nonpoint-source pollution: comes from any places spread over a large area (i.e. runoff collecting pollutants)

50. Water Pollution

51. Water Pollution

52. Water Pollution Nutrient Pollution
eutrophic: body of water that is high in nutrient content but low in oxygen
* Eutrophication can be a natural process (plants decaying in water) or a cultural process (humans polluting water)

53. Water Pollution
cultural eutrophication: nutrient pollution caused by humans
wastewater: water that has been used by humans in some way
* excess phosphorus (in detergents and fertilizers) from nonpoint-source pollution is a major cause of eutrophication

54. Eutrophication

55. Water Pollution

56. Water Pollution
algal blooms: sudden explosions of algal growth caused by excess nutrients

57. Water Pollution
red tide: algal bloom of red algae (phytoplankton and dinoflagellates)
* can be caused naturally and culturally

58. Water Pollution

59. Water Pollution Toxic-chemical pollution (organic or inorganic)
* Petroleum and petroleum products
* plastics (Bisphenol-A aka BPA)
* Pesticides
* Detergents
* Heavy metals (usually point source)
* arsenic
* mercury
* lead

60. Water Pollution

61. Water Pollution Sediment Pollution: caused by erosion
Sediment can cause:
* cloudy water
* decreased photosynthesis
* food web collapse
* degraded water quality

62. Water Pollution
Thermal pollution: putting warm water into surface water
* warm water cannot hold as much oxygen as cold water
* plants and fish cannot tolerate drastic temperature changes or decreased oxygen

63. Water Pollution
Thermal Pollution

64. Water Pollution Biological Pollution
pathogens: disease-causing organisms (bacteria, protozoa, fungi, viruses)
* when pathogens enter our air, soil or water, it is called biological pollution
* may also include intestinal worms

65. Water Pollution

66. Shanghai River
Hengliaojing Creek in Shanghai

67. Water Pollution Groundwater Pollution
* usually not discovered until it is found in drinking water
* human activity is the main cause
* fertilizers, pesticides, leaky underground storage tanks leach below the water table

68. Water Pollution

69. Water Pollution Ocean Water Pollution * Oil Spills * Mercury Pollution
* Nutrient Pollution (Red Tide)

70. Water Pollution

71. Water Pollution

72. Controlling Water Pollution
The Clean Water Act in 1977
* no point source pollution without a permit
* set standards for pollution levels

73. Controlling Water Pollution
Drinking Water Treatment
1. Filtration
2. Coagulation
3. Settling
4. Second Filtration
5. Chlorination
6. Aeration
7. Additional Treatment

76. Controlling Water Pollution
Wastewater treatment
1. Raw Sewage enters
2. Screens and grit tank (solid filtration)
3. Primary clarifier (oils, greases, and solids removed
4. Aeration basin (oxygen added for bacteria)
5. Secondary clarifier
6. Filtering and disinfection
7. Effluent discharged into waterways

77. Controlling Water Pollution

80. Wastewater Treatment
Septic System