1. Tapping groundwater – problems Saltwater Intrusion –Normal interface between freshwater and saltwater moves inland –Figure 15-17

3. Subsidence: –Land sinks

4. Sinkholes –Roof of cavern collapses

7. Reducing Water Waste

9. Why do we really waste so much? Underpricing! We don’t really pay for it!!!!

10. Conventional Irrigation “About 60% of the irrigation water applied throughout the world does not reach targeted crops.” –Most lost to evaporation and run-off

11. Examples: Flood irrigation:

12. Conventional spray irrigation:

13. More efficient irrigation technologies include:

14. Center Pivot

16. LEPA: Low Energy Precision Application

17. Drip Irrigation, Microirrigation

19. Other ways to reduce water waste:

20. Xeriscaping Replace green lawns with vegetation adapted to the climate! (natural)

23. Gray Water System

25. Using storm run-off

28. This storm water system will reduce the building’s water bill by 90% and save water resources

29. In the U.S.: Flushing toilets with water clean enough to drink is the single largest use of domestic water.

31. Solution: Desalinization?? – Reverse osmosis or Distillation –Disadvantages: Expensive Energy Intensive Produces Briny Water

33. Water Pollution

36. Major Categories: Table 22-1

42. Point Source: discharge pollutants at specific locations

43. Non-Point Source: scattered and diffuse; can not be traced to any single point.

45. –The leading Non-Point Source of water pollution:

46. Eutrophication: Natural nutrient enrichment

47. Cultural Eutrophication: excessive inputs of nutrients due to human activities. What are NUTRIENTS????

48. –Produce “blooms” of algae, cyanobacteria, or aquatic plants –Initially, produce Oxygen; however, massive die-offs and decomposition via bacteria sucks OUT all Oxygen –Ecosystem suffocates !!

50. Animal wastes Fertilizer run-off (agricultural and domestic) Sewage –80-90% of raw sewage in developing countries dumped directly into lakes/streams –Approx. 85% of raw sewage from people around Mediterranean Sea dumped along the coast

51. 1.3 billion tons of animal waste produced in the U.S. Pollution strength up to 160 times greater than raw municipal waste. Animal wastes contribute to large oceanic “dead zones,” which extended to nearly 7,903 sq. miles in the Gulf of Mexico during Summer of 2007.

53. Dead Zones Oxygen Depleted Zones Also known as Hypoxic or Anoxic conditions HAB’s: harmful aglal blooms –Red, green, or brown TOXIC tides

56. A few of the world’s dead zones…

58. Water Quality Parameters

59. Fecal Coliform Colonies

60. Measuring Turbidity using a Secchi Disc