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APES - Chaper 19 1
Chapter 19 – Water
Pollution
Miller – Living in the Env. 13th
Edition
Water Pollution – Index Slide
Water
Pollution
Defined
Categories of
Water
Pollution
Sag Curve Groundwater
Pollution
Ocean
Pollution
Waste Water
Treatment
Drinking
Water
Treatment
Water
Pollution
Poster
Children
Images of
water
Pollution
Eutrophication
Other Facts
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Basics
Water Pollution – Any physical, biological,
or chemical change in water quality that
adversely affects living organisms or
makes water unsuitable for desired uses
Point Source – single, identifiable source
of pollutants
Non-point Source – scattered or diffuse
sources – includes atmospheric deposition
APES - Chaper 19 4
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More Numbers
Developed countries
95% of populations have clean water
90% populations have sewage treatment
Less Developed Countries
2.5 to 3.0 billion people lack adequate
sanitation
1.5 billion lack clean water
80% of illness related to water/sewage
2 million childhood deaths due to poor
sanitation
APES - Chaper 19 6
Categories of Water Pollutants
Oxygen Demanding Wastes
Inorganic Chemical
Organic Chemicals
Plant Nutrients
Sediment
Radioactive materials
Heat (thermal pollution)
APES - Chaper 19 7
Focus-Stream Pollution Impacts on streams
Point and non-point pollutants
Sediment, industrial, agricultural wastes most
common
Remediation
Recovery rate and success usually dependent on
oxygen content of water (BOD)
Riparian and wetland areas critical to stream health
through entrapment of pollutants
Dilution is not always the solution to pollution
APES - Chaper 19 8
Oxygen Demand
BOD – biological oxygen demand
Measure of how much dissolved O2 in water is
consumed by aquatic and micro organisms
over a 5 day period
High BOD indicates poor stream health (need
for additional oxygen to meet demands)
DO dissolved oxygen due to plant
contributions and turbulance
Oxygen Sag – decrease in DO downstream
from a pollution source
APES - Chaper 19 9
Clean Zone
Normal O2
Trout, perch,
macro invert
Decompositio
n Zone
Pollutant
enters
Trash fish
Septic Zone
Fish absent,
sludge, worms,
Recovery
Zone
Trash Fish,
leeches,
isopods
Clean Zone
Normal O2
Trout, perch,
macro invert
DO
BOD
Oxygen Sag Curve
Upstream Downstream
APES - Chaper 19 10
Focus-Freshwater Lakes Impacts to Lakes
Water often stratified, slow to exchange
Contaminants remain trapped in sediments
Small bodies have limited water volumes
More vulnerable than streams to: • Plant nutrients
• Oil
• Pesticides/herbicides
• Toxic metals/inorganic substances
Biomagnification impact greater on freshwater fish species
APES - Chaper 19 11
Great Lakes-some numbers
95% of U.S. fresh surface water
20% of World fresh surface water
Impacted by population of 38+ million
people, major industrial centers
Very low/slow water exchange rates (1%)
1960’s – Lake Erie declared dead
Situation has improved, but still much work
to return waters to healthy condition
APES - Chaper 19 12
Groundwater Pollution
Out of site, out of mind
Serious contamination due to:
Surface infiltration
Landfill leaching
Agricultural contaminants
Lowered water tables and flow rates
Difficulty in detecting toxins
Difficulty in cleaning up toxins
APES - Chaper 19 13
Groundwater Pollution
Prevention – much easier than cleanup!
Monitoring programs
Leak detection and remediation of
underground storage tanks
Restrictions on landfill wastes
Restrictions on hazardous waste storage sites
Use good livestock waste management
techniques
APES - Chaper 19 14
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Ocean Pollution
No, it’s not too big to pollute! Man has
proven that!!!!
Pollutants come from:
On-shore refuse and toxin disposal
Marine dumping and disposal
Untreated waste disposal into marine bodies
Major impact on coastal areas
Estuaries, coastal swamps, shorelines
APES - Chaper 19 16
Ocean Pollution
Most polluted marine areas are:
Area around India, SE Asia
Pacific Gyre (Trash Island)
Mediterranean Sea
Large estuaries (Chesapeake Bay, others)
Gulf Coast (agricultural runoff, oil production)
APES - Chaper 19 17
Water Treatment
Developed countries treat sewage to eliminate:
Particulate and biological activity
Rarely treat inorganic toxins like lead, mercury, steroids, pesticides, etc.
U.S. Drinking water treated to achieve
Clarity
0% bacterial contaminants
Other contaminants per U.S. EPA standards
APES - Chaper 19 19
Coarse Screen trash
separation
The following
pictures are from
the Statesville
Waster Water
Treatment Facility
Individual pictures
are referenced to
the Oxygen Sag
Curve Zones
APES - Chaper 19 20
Aeration (Decomposition Zone-
High BOD met by mechanical
aeration)
APES - Chaper 19 21
Skimmer and Grit Removal
(Recovery Zone – bio solids removed, high bacterial count)
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Dewatered Bio solids –
used as fertilizer
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Final Discharged Water
heading for Third Creek
(Clean Zone)
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Laws to Know
Safe Drinking Water Act of 1974
Established maximum levels for many toxins
Clean Water Act
Focus on water quality of U.S. lakes and
streams
Standards for “body contact” and water quality
APES - Chaper 19 27
Water Pollution “Poster Children”
Yellow River, China – sediments, very low flow volumes, high level of organic, inorganic chemical contaminants
Colorado River, U.S. – low flow volumes, salt buildup, dams
Lake Chad, Africa – diversion of water for irrigation, salt buildup
Aral Sea, Kazakhastan – diversion of water for irrigation, salt buildup
APES - Chaper 19 28
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Ganges River,
India
APES - Chaper 19 31
NPR – Oil Rig and slick in
Gulf of Mexico
APES - Chaper 19 32
Changes and
loss of the
Aral Sea
APES - Chaper 19 33
Japanese Nuclear Power Plant
APES - Chaper 19 34
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Plant Nutrients
Cultural Eutrophication
Increased nutrient load in water systems due to human activity
• Nitrogen, phosphate, ammonium as runoff from agriculture, feed lots
• Over-fertilizes algae, water plants
• Increases reproduction rate of plants
• Plants then die and decay which uses dissolved oxygen (DO)
• Aquatic life dependent on O2 content of water dies of suffocation!
APES - Chaper 19 36
Cultural Eutrophication cont.
Examples
Mediterranean Coast – +85% of sewage from
cities enters ocean untreated!
Farm Runoff – over fertilization or runoff of
nutrients to waterways
Mississippi River – concentrated municipal
and farm waste, higher water temperatures
cause hypoxia in Gulf most summers. Area
affected growing annually!.
Some Extras
The following slides simply list
some types of water pollutants
that you should know
APES - Chaper 19 37
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Oxygen Demanding Waste
Any waste that increases the demand for
oxygen to decompose or “clear” a body of
water. Typically plant nutrients from
animal, human waste or agricultural runoff.
Numbers:
DO of > 6ppm supports desirable aquatic life
DO of < 2ppm supports worms, detritus
feeders
APES - Chaper 19 39
Inorganic Chemicals
Acids, caustics, salts, metals • Industrial and household wastes
• Lead, mercury, tin, cadmium
• Selenium, arsenic (often from natural sources)
• Many are neurotoxins that accumulate in tissue to
reach toxic levels
• Chronic health impacts
Salts – in irrigation water of Colorado
River, Asia, Middle East
APES - Chaper 19 40
Organic Chemicals
Organic Chemicals
Pesticides, detergents, gasoline
Industrial and household wastes which end up
in landfills and may leak into water supplies
Agricultural runoff
• 500,000 tons of pesticides used in U.S. annually!
• Golf courses largest users of herbicides and
pesticides; followed by U.S. household use.
Bioaccumulation
APES - Chaper 19 41
Sediments
Sedimentation
Excessive sediment in water
Leads to “smothering”, reduction of sunlight to
plants, animals
Caused by logging, farming, surface
disturbance. Common after forest fires and
hurricanes which cause surface disturbance.
APES - Chaper 19 42
Other Pollutants
Radioactive materials
Typically the result of mine outflow or industrial waste; some natural occurrence in areas of high concentration
Examples: Rocky Flats, Colorado; Uranium mining areas of Colorado, Utah; Fuel disposal (WIIP, Eastern Idaho)
Heat or Thermal Pollution
Outflow from industrial plants (power plant cooling water)
