1. Miller Chapter 19
Water Pollution

2. Pollution Defined
Any chemical , biological, or physical change in water quality that has a harmful effect on living organisms or makes water unsuitable for desired uses.

3. Types and Sources of Water Pollution
Infectious Agents
Oxygen-Demanding
Inorganic Chemicals
Organic Chemicals
Plant Nutrients
Sediment
Radioactive
Thermal

4. CATAGORIES OF POLLUTANTS

5. I. Methods of Determining Water Quality
A. Coliform Bacteria
0 colonies per 100ml for drinking water
200 colonies per 100ml for swimming

6. B. Biological Oxygen Demand (BOD)
The amount of oxygen needed by decomposers to break down organic material over a 5-day period at 680F

7. Dissolved Oxygen (DO)
Only a few species of fish can survive when the D.O. level drops below 4 ppm
Water
Quality
Good
8-9
Do (ppm) at 20˚C
Slightly
polluted
Moderately
Heavily
Gravely
6.7-8
Below 4.5
Below 4

8. C. Chemical Analysis
Determine the levels of organic and inorganic pollution

9. D. Indicator Species
Indicator species can be used to monitor water quality
Ex: Mussels, Cattails, Insect larva
Analyzed to measure the levels of various chemicals

10. II. Sources of Pollution
A. Point Sources
-Discharge from a specific location (pipe, ditch or sewer)
-Easier to identify and regulate
Ex: Factories, Sewage Treatment Plants, Mines, Thermal Outlets and Oil Tankers.

11. B. Non-Point Sources
-Cannot be traced to a specific discharge
-Difficult to identify and control
Ex: Golf Courses, Agriculture, Homes

12. III.Water Pollution A. Rivers and Streams:
-Most pollution in the form of:
chemicals from industry or mines,
malfunctioning sewage plants,
Non-point runoff
Naturally, streams and rivers can rebound:
As long they are not overloaded with pollutants &
Flow is not reduced

13. -The breakdown of degradable wastes by bacteria depletes dissolved oxygen -Reduces the population of oxygen requiring organisms. -Shown as an OXYGEN SAG CURVE

14. Time of distance downstream
Clean Zone
Decomposition
Zone
Septic Zone
Recovery Zone
(Trout, perch, bass,
mayfly, stonefly)
(carp, gar,
Leeches)
Fish absent, fungi,
Sludge worms,
bacteria
(anaerobic)
Normal clean
water organisms
8 ppm
Dissolved oxygen
Biological oxygen
demand
Oxygen sag
2 ppm
Concentration
Types of
organisms
Time of distance downstream
Direction of flow
Point of waste or
heat discharge
Trash fish

15. -Recovery from oxygen depletion is based on the volume of the pollutant and …
Stream Volume
Flow Rate
Temperature
pH level

16. Stream and River Success Stories:
-Water Pollution Control Laws of the 1970’s:
Downstream withdraw of drinking water
Reduce point-source pollution
Increase # of treatment plants
-Ohio’s Cuyahoga River (caught on fire in 1959 and 1969)
Now used for boating and fishing

18. CLEAN WATER ACT and NON-POINT POLLUTION

19. Stream Pollution: The Bad News
Accidental release of organic and inorganic chemicals
Malfunctioning sewage treatment plants
Non-point run-off of pesticides
WORLD WIDE:
2/3 of streams monitored in China and India are severely polluted

20. B. Lakes -More vulnerable than streams due to… Stratified layers,
Little flow,
Low water volumes.
Vulnerable to Biological Magnification &
Cultural Eutrification:
Human activities that increase the level of plant nutrients in lakes

21. Water 0.000002 ppm Herring gull 124 ppm Phytoplankton 0.0025 ppm
Rainbow smelt
1.04 ppm
Zooplankton
0.123 ppm
Phytoplankton
ppm
Water
ppm
Herring gull
124 ppm
Lake trout
4.83 ppm
Herring gull eggs

22. The Terrible Twelve

24. Biological Magnification

25. Cultural Eutrophication
Discharge of untreated
municipal sewage
(nitrates and phosphates)
Nitrogen compounds
produced by cars
and factories
Discharge of
detergents
( phosphates)
Natural runoff
(nitrates and
phosphates
Manure runoff
From feedlots
(nitrates and
Phosphates,
ammonia)
Discharge of treated
municipal sewage
(primary and secondary
treatment:
nitrates and phosphates)
Runoff from streets,
lawns, and construction
lots (nitrates and
phosphates)
Lake ecosystem
nutrient overload
and breakdown of
chemical cycling
Dissolving of
nitrogen oxides
(from internal combustion
engines and furnaces)
Runoff and erosion
(from from cultivation,
mining, construction,
and poor land use)

26. GREAT LAKES READ PAGES 483-484

27. C. Groundwater - Easily contaminated by everyday activities
- Flows slowly so it cannot dilute/disperse contaminants
- Small population of decomposers
- Cold temps. Slow Rx that remove wastes

28. Contaminated Probability
10 to 20 percent
Greater than 20 percent
Not tested

29. - Up to 25% of usable, U.S. groundwater
Extent of Contamination:
- Up to 25% of usable, U.S. groundwater
- 60% of liquid waste injected into deep underground wells
- Pumping of water at coastlines causes contamination of drinking water by saltwater intrusion.

30. Unconfined freshwater aquifer Confined freshwater aquifer
Waste lagoon,
pond, or basin
Mining
site
Pumping
well
Water
pumping
Sewer
Cesspool,
septic
tank
Hazardous
waste
injection
Buried gasoline
and solvent
tanks
Landfill
Road
salt
Unconfined freshwater aquifer
Confined freshwater aquifer
Confined aquifer
Discharge
Leakage
from faulty
casing
Groundwater
Groundwater flow

32. IV. Preventing/Reducing Water Pollution
Prevention:
-Wiser use of fertilizer and pesticides
-Plant buffer zones to control runoff
-Banning Deep Injection Wells
-Monitoring of waterways and aquifers
-Clean Water Act (1977)
-Water Quality Act (1987)

33. 2. Reduction: - Septic Systems Septic tank Nonperforated Manhole (for
Household
wastewater
Perforated
pipe
Distribution
box
(optional)
Septic tank
Manhole (for
cleanout)
Drain
field
Vent pipe
Nonperforated
Gravel or
crushed
stone

34. -Sewage Treatment
3 Levels of Purification
A. Primary –
mechanical treatment
B. Secondary –
biological treatment
C. Advanced –
Specialized chemical and physical processes to remove specific contaminants

35. Disposed of in landfill or ocean or applied to cropland,
Raw sewage
from sewers
Bar screen
Grit
chamber
Settling tank
Aeration tank
Chlorine
disinfection tank
Sludge
Sludge digester
Activated sludge
Air pump
(kills bacteria)
To river, lake,
or ocean
Sludge drying bed
Disposed of in landfill or
ocean or applied to cropland,
pasture, or rangeland
Primary
Secondary
Fig , p. 494

36. reservoirs, or industries
Effluent from
Secondary
treatment
Alum
flocculation
plus sediments
Activated
carbon
Desalination
(electrodialysis
or reverse osmosis)
Nitrate
removal
Specialized
compound
(DDT, etc.)
98% of
suspended solids
90% of
phosphates
dissolved
organics
Most of
dissolved salts
Recycled to land
for irrigation
and fertilization
To rivers, lakes,
streams, oceans,
reservoirs, or industries

37. What about the Sludge?
Sewage sludge is a highly toxic mix of chemicals, infectious agents, and settle solids.
-9% converted to compost
-36% applied as fertilizer
-55% dumped in landfills or burned

38. -Wastewater Gardens Sewage Treated water Wetland type plants
(1) Raw sewage drains by
gravity into the first pool
and flows through a long
perforated PVC pipe into
a bed of limestone gravel.
(3) Wastewater flows through
another perforated pipe
into a second pool, where
the same process is repeated.
(2) Microbes in the limestone gravel
break down the sewage into
chemicals, that can be absorbed
by the plant roots, and the gravel
absorbs phosphorus.
(4) Treated water flowing from the
second pool is nearly free of
bacteria and plant nutrients.
Treated water can be recycled
for irrigation and flushing toilets.
45 centimeter
layer of limestone
gravel coated with
decomposing bacteria
First concrete pool
Second concrete pool
Sewage
Wetland type
plants
Treated
water

39. -Double Vault Systems and Dry Toilets

40. V. Drinking Water Quality
In U.S. we have safe drinking water standards set by the Safe Drinking Water Act of 1974
Establishes Maximum Contamination Levels for any pollutants.
Effects “city” water only, not wells.
Purification of water done in various ways

41. -1/3 of all bottled water is contaminated with bacteria
-International Bottled Water Association sets/maintains standards for bottled water.