1. Chapter 5 Water Quality Prof. Dr. Ali El-Naqa Hashemite University June 2013

2. Chapter Headings Water Pollution Basic Parameters of Water Inorganic Chemicals Organic Chemicals Waterborne Diseases Water Quality Management 3. Water Pollution Water pollution can affect Surface waters Ground waters Can occur naturally but is usually due to mans activities US waters have improved significantly since the Clean Water Act Amendments were passed in 1972 But many waters still dont meet standards 4. Point Source Pollution Contamination discharged through a pipe or other discrete, identifiable location Relatively easy to quantify and evaluate impact Historically, the focus of regulation Water. 1993. National Geographic Special Edition 5. Point Sources Factories and sewage treatment plants Landfills Abandoned mines Underground and above-ground storage tanks 6. Nonpoint Source Pollution Contamination from a diffuse source Difficult to measure Focus of recent regulatory efforts Soil erosion from a farm field Gary Hawkins, UGA 7. Nonpoint Sources Lawns, gardens, and golf courses Agricultural and forestry practices Street refuse Construction activities Stormwater runoff 8. Chapter Headings Water Pollution Basic Parameters of Water Inorganic Chemicals Organic Chemicals Waterborne Diseases Water Quality Management 9. Basic Parameters of Water Temperature Dissolved oxygen (DO) pH Turbidity 10. Temperature Temperature affects physical, chemical, and biological processes in water Chemical example: DO decreases as temperature increases Biological example: fish seek thermal refuges Temperature affected by depth Causes lake turnover Loss of streamside shade trees causes temperature to increase 11. Dissolved Oxygen Atmosphere consists of 21% O2 Water consists of hypereutrophic Happens over 100s of years Excessive inputs of P speed up the process Call this accelerated eutrophication Happens over 10s of years Concentrations as low as 0.01 ppm stimulate algae 29. Lake Aging Natural Process Accelerated by land use 30. Nutrients: Phosphorus Lake in Manitoba Province of Canada Divided by plastic curtain For 8 years N and C added each year to one side N, C, and P added to other side Every year there was an algal bloom in response to adding P www.umanitoba.ca/institu tes/fisheries/eutro.html 31. Nutrients: Phosphorus Disinfection byproducts Occur when lake with algal bloom is a source of public drinking water Chlorine used to disinfect water Chlorine combines with organic carbon to produce carcinogens Taste and odor events Certain types of algae produce organic compounds that give drinking water a dirty taste and foul odor 32. Nutrients: Phosphorus Atlanta Journal Constitution 17 Sep 2007 33. Nutrients: Phosphorus Sources: manures, fertilizers, sewage, detergents Not very mobile in soils Usually doesnt leach to groundwater Instead it runs off into streams Dissolved in runoff or Attached to eroded sediment particles Not harmful to humans directly P was banned from detergents in 1990s 34. Phosphorus concentrations in the Chattahoochee below Atlanta 35. Nutrients and Marine Waters Algal growth in marine waters is controlled primarily by N P can be important at certain times of the year Estuaries (which are intermediate between fresh and marine waters in terms of salinity) are affected by both N and P 36. Gulf of Mexico Hypoxia Nitrogen from the Mississippi River watershed is causing algal blooms and low DO (hypoxia) in the Gulf of Mexico each summer Dead zone at lower depths kills aquatic species including shrimp 37. Chapter Headings Water Pollution Basic Parameters of Water Inorganic Chemicals Organic Chemicals Waterborne Diseases Water Quality Management 38. Organic Chemicals Compounds that do contain carbon (C) Often large complex molecules May be natural or man-made (synthetic) Synthetic compounds may last for a long time in the environment Natural decomposing processes are unable to break down these complex molecules 39. Organic Chemicals Many synthetic organic chemicals are carcinogens: Benzene (C6H6), commercial solvent Carbon tetrachloride (CCl4), in fire extinguishers, solvents, and cleaning agents Polychorinated Biphenyls (PCBs), used as a coolant in electrical transformers Pesticides are synthetic organic chemicals used to kill unwanted pests Can be harmful to humans and wildlife 40. Chapter Headings Water Pollution Basic Parameters of Water Inorganic Chemicals Organic Chemicals Waterborne Diseases Water Quality Management 41. Waterborne Diseases Early concerns regarding water quality caused by waterborne diseases Plagues in the Middle Ages Cholera epidemic in 1848-1849 caused 53,000 deaths in London Connection between disease and water was unknown until shown by Dr. John Snow 1854 Broad Street Pump study 42. Dr. John Snow Found that cholera causes were clustered around a community water pump at Broad Street in London Water company that supplied pump took it from Thames River downstream of London Advised that the pump handle be removed 43. Replica of Broad Street pump with handle removed outside the John Snow pub www.ph.ucla.edu/epi/snow 44. Waterborne Diseases Microorganisms include Viruses bits of DNA or RNA Bacteria single cell organisms Other protozoa, worms, blue-green algae Examples of microorganisms that are pathogens (disease-causing organisms) Escherichia coli (E. coli) bacterium Giardia protozoa Cryptosporidium protozoa 45. E. Coli E. coli are a common bacteria in the human intestines Aid digestion, harmless Used as an indicator organism One strain of E. coli (0157:H7) is lethal, however In a town in Ontario in 2000, 2,300 people became ill and 7 died when the water supply became contaminated with 0157:H7 Attributed to contamination from cattle manure 46. Spinach E. Coli Outbreak 2006 205 illnesses 3 deaths 47. Indicator Organisms Too costly and dangerous to test water for individual pathogens Instead we test for indicator organisms Harmless but indicate fecal origin Common indicator organism Total coliform bacteria seldom used today Fecal coliform bacteria most common today 48. Indicator Organisms Standard for drinking water in Georgia is