Transcript Major Human Sources

Water Pollution
Key Concepts
 Types, sources, and effects of water pollutants
 Major pollution problems of surface water
 Major pollution problems of groundwater
 Reduction and prevention of water pollution
 Drinking water quality
Refer to Tables 22-1
and 22-2 p. 492 and
493
Types of Water Pollution
INFECTIOUS AGENTS
Examples: Bacteria, viruses, protozoa, and parasitic
worms
Major Human Sources: Human and animal wastes
Harmful Effects: Disease
Water Contamination - Milwaukee
OXYGEN-DEMANDING WASTES
Examples: Organic waste such as animal
manure and plant debris that can be
decomposed by aerobic (oxygenrequiring) bacteria
Major Human Sources: Sewage, animal
feedlots, paper mills, and food processing
facilities
Harmful Effects: Large populations of
bacteria decomposing these wastes can
degrade water quality by depleting water
of dissolved oxygen. This causes fish and
other forms of oxygen-consuming aquatic
life to die.
INORGANIC CHEMICALS
Examples: Water-soluble 1) acids, (2) compounds of toxic
metals such as lead (Pb), arsenic (As), and selenium Se),
and (3) salts such as sodium chloride (NaCl) in ocean water
and fluorides (F–) found in some soils
Major Human Sources: Surface runoff, industrial effluents, and
household cleansers
Harmful Effects: Can (1) make fresh water unusable for
drinking or irrigation, (2) cause skin cancers and crippling
spinal and neck damage (F–), (3) damage the nervous
system, liver, and kidneys (Pb and As), (4) harm fish and
other aquatic life, (5) lower crop yields, and (6) accelerate
corrosion of metals exposed to such water.
Minamata Bay
Types of Water Pollution
ORGANIC CHEMICALS
Examples: Oil, gasoline, plastics, pesticides,
cleaning solvents, detergents
Major Human Sources: Industrial effluents,
household cleansers, surface runoff from
farms and yards
Harmful Effects: Can (1) threaten human
health by causing nervous system
damage (some pesticides), reproductive
disorders (some solvents), and some
cancers (gasoline, oil, and some solvents)
and (2) harm fish and wildlife.
RADIOACTIVE MATERIALS
Examples: Radioactive isotopes of iodine,
radon, uranium, cesium, and thorium
Major Human Sources: Nuclear and coalburning power plants, mining and
processing of uranium and other ores,
nuclear weapons production, natural
sources
Harmful Effects: Genetic mutations,
miscarriages, birth defects, and certain
cancers
PLANT NUTRIENTS
Examples: Water-soluble compounds
containing nitrate (NO3 –), phosphate
(PO43–), and ammonium (NH4+) ions
Major Human Sources: Sewage, manure, and
runoff of agricultural and urban fertilizers
Harmful Effects: Can cause excessive growth
of algae and other aquatic plants, which die,
decay, deplete water of dissolved oxygen,
and kill fish. Drinking water with excessive
levels of nitrates lowers the oxygen-carrying
capacity of the blood and can kill unborn
children and infants (“bluebaby syndrome”).
HEAT (THERMAL POLLUTION)
Examples: Excessive heat
Major Human Sources: Water cooling of electric power
plants and some types of industrial plants. Almost
half of all water withdrawn in the United States each
year is for cooling electric power plants.
Harmful Effects: Lowers dissolved oxygen levels and
makes aquatic organisms more vulnerable to
disease, parasites, and toxic chemicals. When a
power plant first opens or shuts down for repair, fish
and other organisms adapted to a particular
temperature range can be killed by the abrupt
change in water temperature—known as thermal
shock.
Types of Pollution
SEDIMENT
Examples: Soil, silt
Major Human Sources: Land erosion
Harmful Effects: Can (1) cloud water and reduce
photosynthesis, (2) disrupt aquatic food webs, (3)
carry pesticides, bacteria, and other harmful
substances, (4) settle out and destroy feeding
and spawning grounds of fish, and (5) clog and fill
lakes, artificial reservoirs, stream channels, and
harbors.
Water Pollution
and Solubility
Hypoxia and Anoxia
Area Most
Effected:
Gulf of Mexico
Long Island
Sound
WHY?
Eutrophication –
Nutrient pollution
Chesapeake Bay
Largest US estuary
Relatively shallow
Slow “flushing” action to
Atlantic Major problems
with dissolved O2
Biomagnification
Water
0.000002 ppm
Phytoplankton
0.0025 ppm
Herring gull
124 ppm
Herring gull eggs
124 ppm
Zooplankton
0.123 ppm
Lake trout
4.83 ppm
Rainbow smelt
1.04 ppm
Figure 22-6
Page 498
Silent Spring
Pollution Sources and Effects
Nonpoint Sources
Point Sources
Rhine River
Minamata Bay
Oxygen Sag Curve
Factors that influence
dissolved oxygen in the water
Biological Oxygen demand
Recovery
Case Study: The Great Lakes
An Industrial Legacy
Great Lakes
Fig. 22-8 p. 500
Groundwater Pollution
Gasland
Causes:
Love Canal
Low flow rates
Spills
Low oxygen
Landfill leachate
Few bacteria
pesticides /fertilizers
Cold temperatures
waste lagoons
Times Beach
Aquifer cleanup
Ocean Pollution
Message from
the waves
Fig. 22-11 p. 504
Troubled Waters
Oil Spills

Sources: offshore
wells, tankers,
pipelines and storage
tanks

Effects: death of
organisms, loss of
animal insulation and
buoyancy,
smothering

Significant economic
impacts

Mechanical cleanup
methods: skimmers and
blotters

Chemical cleanup
methods: coagulants and
dispersing agents
1. Name 3 types of water pollution. Identify the
sources, and effects of each.
2. What is bioaccumulation?
3. What is biomagnification?
4. Give an example of a pollutant that exhibits
biomagnification.
Solutions: Preventing and Reducing Surface Water
Pollution
Nonpoint Sources

Reduce runoff


Buffer zone vegetation
Reduce soil erosion
Point Sources

Clean Water Act (1972)

Water Quality Act (1965):
Established water purity
standards with states
retaining initial responsibility
for water purity.
Water Laws:
• Clean Water Act (1972): Established the basic structure for regulating discharges of
pollutants into the waters of the United States. It gave the EPA the authority to
implement pollution control programs such as setting waste-water standards for
industry.
•
Federal Water Pollution Control Act (1948): Created comprehensive programs for
eliminating or reducing the pollution of interstate water and improving the sanitary
condition of surface and underground water supplies.
•
Safe Drinking Water Act (1974): Established standards for safe drinking water in
the United States.
•
Ocean Dumping Ban Act (1988): Made it unlawful for any person to dump or
transport for the purpose of dumping sewage, sludge, or industrial wastes into the
ocean.
•
Oil Spill Prevention and Liability Act (1990): Strengthened the EPA's ability to
prevent and respond to catastrophic oil spills.
•
Source Water Assessment Program—SWAP (1996): Required states to identify
sources of public drinking water supplies and assess susceptibility to
contamination.
•
Source Water Protection Program—SWPP (1996): Encouraged states to adopt a
community-based approach to preventing water pollution.
•
Surface Water Treatment Rule—SWTR (1996): Addressed control of microbial
pathogens, including cryptosporidium.
Water Treatment
Municipal
Waste Water
Treatment
Wastewater treatment High-Tech v. Low-Tech
Hyperion Wastewater Treatment
Plant – Los Angeles
Solar Aquatic
Waste Treatment
Treating mining
wastewater
Z-weed
Desalinization
Wetlands treating sewage
Technological Approach: Septic
Systems

Require suitable soils and
maintenance
Technological Approach: Sewage
Treatment

Physical and biological treatment
Fig. 22-15 p. 510
•Advanced Tertiary Treatment
•Uses physical and chemical processes
•Removes nitrate and phosphate
•Expensive
•Not widely used
“Municipal” Water Treatment Process"
Coagulation: Alum and other chemicals are added to water to form tiny sticky particles,
called floc, that attract dirt particles.
Flocculation: The water is stirred slowly with paddles to mix the alum with the dirty
water.
Sedimentation: The water is no longer stirred and is allowed to settle. The heavy
particles (floc) settle to the bottom and clear water moves off the top to the filtration
chamber.
Filtration: Water passes through filters that help remove even smaller particles. Our
filters consist of gravel, sand, garnet and charcoal. Each layer filters out a smaller and
smaller particle. The charcoal not only acts as a filter but neutralizes taste and odor.
Disinfection: After filtration, the water moves into a disinfection chamber where it is
mixed with chlorine. A small amount of chlorine is added to kill any bacteria or
microorganisms that may be in the water. It is at this step that we also add a small
amount of fluoride for dental health.
Storage: Water is placed in a closed tank or reservoir where it flows through pipes to
homes and businesses in the community
Drinking Water Quality

Purification of urban drinking water

Protection from terrorism

Purification of rural drinking water

Safe Drinking Water Act

Maximum contaminant levels (MCLs)

Bottled water
Water Video Clips
•
•
•
•
Composting Toilets & Z-weed
Drinking Water from a Contaminated Aquifer
Desalinization
Drugs in water
Persistent Organic pollutants (POPs)
The “Dirty Dozen” or “Terrible Twelve”
aldrin1
hexachlorobenzene1,2,3
chlordane1
mirex1
DDT1
toxaphene1
dieldrin1
polychlorinated biphenyls (PCBs)2,3
endrin1
polychlorinated dibenzo-p-dioxins (dioxins)3
heptachlor1
polychlorinated dibenzo-p-furans (furans)3
1Pesticide
2Industrial
3Byproduct
Chemical
PCBs
Unknown Pollution Threats
PAHs
Pharmaceuticals in the water
supply