This document discusses water quality parameters and pollution. It covers topics like point and nonpoint pollution sources, inorganic chemicals like arsenic and nutrients like phosphorus that can cause algal blooms. Water quality is managed through programs that monitor parameters and pollutants in surface and groundwater to protect ecosystems and human health.

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 man’s activities
 US waters have improved significantly since the Clean
Water Act Amendments were passed in 1972
 But many waters still don’t meet standards

5. 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

6. Point Sources
 Factories and sewage treatment plants
 Landfills
 Abandoned mines
 Underground and above-ground storage tanks

7. 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

8. Nonpoint Sources
 Lawns, gardens, and golf courses
 Agricultural and forestry practices
 Street refuse
 Construction activities
 Stormwater runoff

9. Chapter Headings
 Water Pollution
 Basic Parameters of Water
 Inorganic Chemicals
 Organic Chemicals
 Waterborne Diseases
 Water Quality Management

10. Basic Parameters of Water
 Temperature
 Dissolved oxygen (DO)
 pH
 Turbidity

11. 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

12. Dissolved Oxygen Atmosphere consists of 21% O2
 Water consists of <1% O2
 When water and atmosphere come into intimate
contact, O2 tends to diffuse into water
 Occurs as water passes over riffles, rapids, and falls and
to a lesser extent in still water
 Aquatic plants also pump O2 into water
 During daytime when they are undergoing
photosynthesis

13. Dissolved Oxygen
 Fish depend on DO in
water
 O2 diffuses from water
to blood in gills
 When DO
concentrations in water
drop below 5 milligrams
per liter (mg/L) most
fish have trouble
www.fishdoc.co.uk

14. pH

15. pH
 pH = power of 10 for the H ion concentration (drop the
minus sign)
 Pure distilled water has a pH of 7 (neutral)
 1 x 10-7 = 0.0000001 moles H+ per liter
 Most rivers and lakes have a pH of 4 to 9
 Fish have a narrow range that varies by species
 pH outside the range can cause damage to gills, eyes,
skin, etc.

16. Turbidity
 Clarity of water
 Measured as light
penetration in
nephelometric turbidity
units (NTU)
 Also measured with a
Secchi disk
 Record the depth at
which you can no longer
see the banded colors
on the disk

17. Secchi disk depth comparison from clear (left) to murky (right)
http://earthobservatory.nasa.gov/Study/WaterQuality/water_quality2.html

18. Chapter Headings
 Water Pollution
 Basic Parameters of Water
 Inorganic Chemicals
 Organic Chemicals
 Waterborne Diseases
 Water Quality Management

19. Inorganic Chemicals
 Compounds that do not contain carbon (C)
 Originally defined as compounds that do not originate
in plants or animals
 Metals, minerals, and nutrients1
1book lists nutrients under organic compounds but most
nutrients are in the inorganic form

20. Metals Lead
 Used in electrical conductors, pipes (soldering), paints,
and a by-product of mining
 Lead poisoning causes toxic reactions, brain damage,
death
 Especially harmful to brain development in children
 Arsenic
 Found naturally in some rocks, in banned pesticides,
wood preservatives, and as an industrial by-product
 Causes neurological damage and cancers
 Drinking water standard used to be < 50 ppb
 Starting Jan 2006 it is < 10 ppb

21. Notice in Shanghai store says Barbie dolls are out of stock
Financial Post Canada.com

22. Arsenic in Bangladesh Wells
 For past 30 years, Bangladesh had a program to drill
wells for cleaner drinking water
 Traditional drinking water source was surface waters
contaminated with cholera, fecal bacteria, etc.
 5 million wells drilled
 83% of wells have toxic levels
 Arsenic occurs naturally in rock
www.uswaternews.com/archives/arcglobal/tarspoi4.html

23. Minerals
 All surface and groundwaters contain minerals
 At high concentrations they can cause adverse
effects
 Salt: sodium chloride (NaCl)
 Salinity: the presence of excess salts in water or in soil
 Saline water is undrinkable
 Saline soils make water uptake difficult for plants and
microbes
 Aquatic plants and animals sensitive to salinity (oysters
in Apalachicola Bay)

25. Colorado River and Salt
 U.S. irrigation and water withdrawals cause Colorado
River salinity to be very high by the time it reaches
Mexico
 1974 law requires average annual salt concentration be
<115 ppm at border
 Battery of wells at border
 13-mile long 5-mile wide area
 Pump low salinity groundwater into river to dilute salt
concentrations

26. Nutrients
 Major minerals important in animal and plant
nutrition:
 Nitrogen, phosphorus, potassium, calcium
 Trace elements also required in
 Iron, zinc, manganese, etc.
 At high concentrations in streams and lakes they can
cause problems

27. Nutrients: Nitrogen
 Nitrogen (N) an important plant nutrient
 Takes several forms in nature
 Nitrogen gas (N2)
 Nitrate (NO3
-)
 Ammonia gas (NH3)
 Ammonium (NH4
+)
 Organic forms

29. Nutrients: Nitrogen
 Nitrate in drinking water is a pollutant
 When ingested by babies in milk formula
 Causes methemoglobinemia or blue baby syndrome
 Converts to nitrite (NO2
-) which interferes with oxygen
transport in the blood
 Baby suffocates
 Drinking water standard is <10 ppm nitrate
 Very mobile in soil and leaches easily to
groundwater
 Sources: manures, fertilizers, sewage

30. Nutrients: Phosphorus Phosphorus (P) an important plant and animal
nutrient
 Can cause excessive algal growth in lakes
 A little bit of algal growth is good
 Source of food for fish
 Too much is bad
 Microbes that decompose dead algae use oxygen and lower
DO
 Low DO stresses fish, forcing them to the surface, selecting
against species such as trout, and even causing fish kills

31. Nutrients: Phosphorus Over time, lakes lose depth and naturally evolve
from low nutrient to high nutrient status
 Oligotrophic => mesoptrophic => eutrophic =>
hypereutrophic
 Happens over 100’s of years
 Excessive inputs of P speed up the process
 Call this accelerated eutrophication
 Happens over 10’s of years
 Concentrations as low as 0.01 ppm stimulate algae

32. Lake Aging
Natural Process Accelerated by land use

33. 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

34. 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

35. Nutrients: Phosphorus
Atlanta Journal
Constitution
17 Sep 2007

36. Nutrients: Phosphorus
 Sources: manures, fertilizers, sewage, detergents
 Not very mobile in soils
 Usually doesn’t 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 1990’s

37. Phosphorus concentrations in the Chattahoochee below Atlanta

38. 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

39. 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

40. Chapter Headings
 Water Pollution
 Basic Parameters of Water
 Inorganic Chemicals
 Organic Chemicals
 Waterborne Diseases
 Water Quality Management

41. 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

42. 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

43. Chapter Headings
 Water Pollution
 Basic Parameters of Water
 Inorganic Chemicals
 Organic Chemicals
 Waterborne Diseases
 Water Quality Management

44. 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

45. 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

46. Replica of Broad Street
pump with handle
removed outside the
John Snow pub
www.ph.ucla.edu/epi/snow

47. 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

48. 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

49. Spinach E. Coli Outbreak 2006
205 illnesses
3 deaths

50. 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

51. Indicator Organisms
 Standard for drinking water in Georgia is <1 fecal
coliform per 100 mL
 Standard for streams and lakes is <200 fecal coliforms
per 100 mL

52. Fecal coliforms in the Chattahoochee below Atlanta

53. Chapter Headings
 Water Pollution
 Basic Parameters of Water
 Inorganic Chemicals
 Organic Chemicals
 Waterborne Diseases
 Water Quality Management

54. Water Quality Management We try to manage water quality so that waters don’t
become contaminated (pollution prevention)
 Costly and risky to rely only on treatment of drinking
water (cryptosporidum oocysts unaffected)
 Reduce impact on wildlife
 Book calls this Fate and Transport
 The movement and ultimate disposition of pollutants
 Water quality management programs focus on
ground water and surface water

55. Groundwater Management Pollutants usually move horizontally in a plume away
from the source in groundwater
 Concentration decreases as pollutant gets farther away
from source
 Pollutant may break down with time
 Mixing with uncontaminated groundwater causes
dilution
 Pollutants may be more or less mobile
 Depends on adsorption to soil and rock

57. Groundwater Management
 U.S. EPA Superfund Program established in 1980
 Purpose to clean up highly contaminated point-
sources of pollution
 Currently there are more than 1,200 sites in the U.S.
 80% involve groundwater contamination

58. Groundwater Management
 Example site is Nebraska Ordnance Plant near
Mead, OK
 During WWII and Korean War, bombs were made
at the plant
 Solvent (TCE) and explosive compound (RDX)
were washed from the assembly buildings into
ditches and ponds
 Estimated that 22.5 billion gals of groundwater is
contaminated
 Extraction wells are being used to treat water and
restrict plume migration

60. Surface Water Management
 Water sampling is important part of surface water
quality management
 Only way to know if a river or lake meets the water
quality standard
 Also used to determine if clean up plan is working
 Federal and state agencies take samples
 Also volunteer groups (Adopt-a-Stream)

61. Surface Water Management
 Example of local volunteer group is Upper Oconee
Watershed Network (UOWN)
 http://www.uown.org/
 Quarterly monitoring of Upper Oconee River
 Annual River Rendezvous
 Maintain a database

62. Chapter Summary
 Pollutants come in many forms (inorganic, organic,
nutrients, microorganisms)
 Point and nonpoint sources of pollution
 Pollutants usually come from human activity
 Water quality management programs focus on
preventing pollution before it happens

63. Quiz
 Indicate whether the sources of pollution below are point
or nonpoint sources:
 golf course
 waste water treatment plant
 farm field
 Landfill
 underground storage tank
 construction activity
 Why is dissolved oxygen a water quality issue?
 Who was Dr. John Snow?
 What is an example of an inorganic water quality
pollutant?