Title: Water Pollution
1Water Pollution
2John Todds Living Machine
- Sewage flows into passive solar greenhouse or
outdoor sites containing rows of large open tanks - 1st tanks- algae microorganisms decompose
organic wastes - Water hyacinths, cattails, bulrushes, other
aquatic plants use remaining nutrients
3- Water runs through artificial marsh (sand,
gravel, bulrush plants) that filters out algae
remaining organic wastes - Aquarium tasks- snails zooplankton consume
microorganisms in turn are consumed by
crayfish, tilapia, other fish can be eaten or
sold as bait
4- 10 days later- 2nd artificial marsh
- Purified for drinking by exposing to UV light or
passing through ozone generator
5Water Pollution
- Any chemical, biological, or physical change in
water quality that has a harmful effect on living
organisms or makes water unsuitable for desired
uses
6Table 22-1Page 492
Table 22-1 Major Categories of Water Pollutants
INFECTIOUS AGENTS Examples Bacteria, viruses,
protozoa, and parasitic worms Major Human
Sources Human and animal wastes Harmful
Effects Disease
7Table 22-1Page 492
Table 22-1 Major Categories of Water Pollutants
OXYGEN-DEMANDING WASTES Examples Organic waste
such as animal manure and plant debris that can
be decomposed by aerobic (oxygen-requiring)
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.
8Table 22-1Page 492
Table 22-1 Major Categories of Water Pollutants
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.
9Table 22-1Page 492
Table 22-1 Major Categories of Water Pollutants
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.
10Table 22-1Page 492
Table 22-1 Major Categories of Water Pollutants
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).
11Table 22-1Page 492
Table 22-1 Major Categories of Water Pollutants
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.
12Table 22-1Page 492
Table 22-1 Major Categories of Water Pollutants
RADIOACTIVE MATERIALS Examples Radioactive
isotopes of iodine, radon, uranium, cesium, and
thorium Major Human Sources Nuclear and
coal-burning 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
13Table 22-1Page 492
Table 22-1 Major Categories of Water Pollutants
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
temperatureknown as thermal shock.
14Coliform Bacteria Count
- Presence indicates that water has been exposed to
human or animal waste (contains disease causing
agents)
15Dissolved Oxygen
- Related to the amount of oxygen-demanding wastes
(broken down by oxygen-requiring bacteria plant
nutrients)
16Biological Indicators
- Analyze aquatic plants (cattails) or
bottom-dwellers (mussels) or filter feeders
17Point Source Pollution
- Discharge of pollutants at specific locations
through drain pipes, ditches, or sewer lines into
surface water - Factories
- Underground mines
- Sewage treatment plants
- Oil tankers
18- Easy to identify, monitor, regulate due to
specific location
19Nonpoint Source Pollution
- Large or dispersed land areas that discharge
pollutants into environment over a large area - Acid deposition
- Runoff from croplands, feedlots for livestock,
logged forests, urban streets, lawns, golf
courses, parking lots
20Safe Drinking Water
- 74-95 of people have access to clean drinking
water - - 1.4 billion people do NOT
- - 9,300 die daily due to infectious diseases
spread by contaminated water or lack of water for
adequate hygiene
21Developing Countries
- 26 of people do not have access to clean
drinking water
22Decreased Quality of Surface Water
- Intense downpours more chemicals, plant
nutrients, microorganisms - Massive flooding spread of disease carrying
pathogens into water treatment facilities wells - Overflow of lagoons sewer lines raw sewage
into rivers streams
23- Drought reduced river water to dilute waste
- Spread of disease due to lack of water to keep
clean - Warm temperatures lower dissolved oxygen levels
higher growth rates of bateria
24Pollution of Streams
- Overloaded with pollutants
- Drought
- Damming or water diversion
- Oxygen sag curve depletion of DO by bacteria
reduced populations of organisms with high oxygen
requirements
25Normal clean water organisms (trout, perch,
bass, mayfly, stonefly)
Trash fish (carp, gar, leeches)
Fish absent, fungi, sludge worms, bacteria (anaero
bic)
Trash fish (carp, gar, leeches)
Normal clean water organisms (trout, perch,
bass, mayfly, stonefly)
8 ppm
Types of organisms
8 ppm
Dissolved oxygen (ppm)
Biological oxygen demand
Clean Zone
Recovery Zone
Septic Zone
Decomposition Zone
Clean Zone
Figure 22-5Page 496
26Limiting Factors
- Volume of degradable waste
- Stream volume
- Flow rate
- Temperature
- pH level
27Controlling Stream Pollution in Developed
Countries
- Increased number quality of water-water
treatment plants - Industries are required to reduce or eliminate
point-source pollution - - Accidental or deliberate release of toxic,
inorganic, organic chemicals causes fish kills
contaminates drinking water
28- - Sewage treatment plants malfunction
- - Nonpoint runoff of pesticides excess plant
nutrients from cropland animal feedlots
29Controlling Stream Pollution in Developing
Countries
- - Discharge of untreated sewage industrial
waste - - Only 10 of Chinese city sewage is treated
30Ganges River
- Cremated bodies are returned to river (to
increase chances for heaven) - Bodies are burned in open air wood fires
- Some bodies are dumped into river only partially
burned (decreases DO adds bacteria viruses) - Government adding sewage treatment plants
electric crematoriums
31Diluting Lake Pollution
- Less effective
- Stratified layers with little vertical mixing
- Little flow water is replaced every 1-100 years
(unlike days to weeks for streams)
32Eutrophication
- Physical, chemical, biological changes that
take place after receiving inputs of plant
nutrients (nitrates phosphates) from natural
erosion runoff
33Cultural Eutrophication
- Over nourishment of aquatic ecosystems with plant
nutrients due to human activities (agriculture,
urbanization, discharge from industrial plants
sewage treatment plants
34Eutrophication Prevention
- Use advances ( expensive) waste treatment
systems to remove nitrates phosphates from
waste water - Ban (or limit) use of phosphate in household
detergents other cleaning agents - Soil conservation land-use control to reduce
nutrient runoff
35Eutrophication Cleanup
- Mechanically remove excess weeds
- Control plant growth with herbicides algaecides
- Pump air through lakes reservoirs to avoid
oxygen depletion
36Lake Washington
- Water was diverted into Puget Sound
- Puget sound has rapid exchange rate with Pacific
Ocean - Lake was NOT filled with weeds sediment
- Preventative action
37The Great Lakes
- Decreased algal blooms
- Increased DO levels
- Increased commercial fishing catches
- New or upgraded sewage treatment plants
- Better treatment of industrial wastes
- Ban of phosphate containing cleansers
38- - August- low DO levels kills fish
microorganisms - - ¾ of shoreline is NOT clean enough for swimming
- - Nonpoint pollution is still high
- - Highly polluted sediments in hot spots
- - 80 drop in EPA funded cleanup
39Groundwater Contamination
- Leaking from industrial waste ponds (no liners)
- Leaking of underground tanks (gasoline, diesel
fuel, home heating oil, toxic solvents) - Leaching of nitrate fertilizers
- Soils rock may contain arsenic
- High levels of naturally occurring fluoride
40Serious Problems because
- Removal can be difficult costly
- Slow water movement
- Pollutants can get easily into drinking water
irrigation water
41As a Result
- High fluoride levels crippling spine neck
damage variety of dental problems - High nitrate levels cancers blue baby
syndrome (blood lacks the ability to carry
sufficient oxygen) - High arsenic level cancer (skin, bladder, lung)
42Solutions
Figure 22-10Page 503
Groundwater Pollution
Prevention
Cleanup
Find substitutes for toxic chemicals
Pump to surface, clean, and return to aquifer
(very expensive)
Keep toxic chemicals out of the environment
Install monitoring wells near landfills and
underground tanks
Inject microorganisms to clean up contamination
(less expensive but still costly)
Require leak detectors on underground tanks
Ban hazardous waste disposal in landfills and
injection wells
Pump nanoparticles of inorganic compounds to
remove pollutants (may be the cheapest, easiest,
and most effective method but is still being
developed)
Store harmful liquids in aboveground tanks with
leak detection and collection systems
43Ocean Pollution
- Coastal areas- dumping of sewage industrial
waste, agricultural waste, algal blooms,
oxygen-depleted zones (excessive fertilizers
animal wastes) - 40 of world population lives with 100km (62mi)
of coast
44Ocean Pollution from Rivers
- Plant nutrients from river systems causes algal
blooms (red, brown, green) releases waterborne
airborne toxins that damage fisheries, kills
fish-eating birds, reduces tourism, poisons
seafood
45Chesapeake Bay
- Waste from point nonpoint sources
- Shallow bay
- Sewage treatment industrial plants
- Runoff from urban, suburban, agricultural land
- Deposition from atmosphere
46- Integrated Coastal Management
- Land-using regulations for agricultural urban
runoff - Ban phosphate detergents
- Upgrade sewage treatment plants
- Better monitoring of industrial discharge
47Types of Ocean Pollution
- Dredge spoils- materials (toxic metals) scraped
from bottoms of harbors rivers to clear
shipping channels - Sewage sludge- gooey mixture of toxic chemicals,
infectious agents, settled solids removed from
wastewater at sewage treatment plant
48Ocean Oil Pollution
- Waste oil dumped on ground, poured down drain,
spilled, or leaked onto land or into sewers by
cities, industries, people changing motor oil
49Oil Ocean Ecosystem
- Kills aquatic organisms (especially larval forms)
- Coats bird feather marine mammal fur (destroys
natural insulation buoyancy) - Smothers bottom-dwellers
- Kills coral reef
- Economic impact on coastal residents
50Mechanical Cleanup
- Floating booms contain oil spills from reaching
sensitive areas - Skimmer boats vacuum up oil into collections
barges - Absorbent devices large mesh pillow filled with
feathers or hair to soak up oil on beaches
51Chemical Methods
- Coagulating agents cause floating oil to clump
together - Dispersing agents break up oil slicks
- Fire can burn off floating oil, but crude oil
is hard to ignite produces air pollution
52Cleanup Limitations
- Can only recover 15 of oil
53Reduced Tanker Oil Spills
- Double hulls (by 2015)
- Trust fund for cleanups
- Banning of single hull tankersh
54Solutions
Coastal Water Pollution
Figure 22-14Page 508
Prevention
Cleanup
Reduce input of toxic pollutants
Improve oil-spill cleanup capabilities
Separate sewage and storm lines
Ban dumping of wastes and sewage by maritime and
cruise ships in coastal waters
Sprinkle nanoparticles over an oil or sewage
spill to dissolve the oil or sewage without
creating harmful byproducts (still under
development)
Ban ocean dumping of sludge and hazardous dredged
material
Protect sensitive areas from development, oil
drilling, and oil shipping
Require at least secondary treatment of coastal
sewage
Regulate coastal development
Use wetlands, solar-aquatic, or other methods to
treat sewage
Recycle used oil
Require double hulls for oil tankers
55Reducing Nonpoint Source Pollution
- Prevent soil erosion by keeping cropland covered
with vegetation - Use slow-release fertilizer
- Apply pesticides only when needed
- Use buffer zone around animal feedlots, animal
waste sites, cultivated fields - Use biological controls
56Clean Water Act
- Standards for allowed levels of key water
pollutants required polluters to get permits
for discharge
57Water Quality Act
- Control pollution of surface water
58EPA Discharge Trading Policy
- Uses market forces to reduce water pollution
59Septic Tanks
- Underground tank for treating wastewater from a
home in rural suburban areas - Bacteria decomposes organic waste
- Sludge settles to bottom
- Effluent flows out of tank into ground
60Primary Sewage Treatment
- Mechanical sewage treatment where large solids
are filtered out by screens suspended solids
settle out as sludge in sedimentation tank
61Secondary Sewage Treatment
- 2nd step- aerobic bacteria decomposes 90 of
degradable, oxygen-demanding organic wastes - Sewage bacteria is brought together in
trickling filters or in activated sludge process
62Septic tank with manhole (for cleanout)
Household wastewater
Nonperforated pipe
Distribution box (optional)
Figure 22-15Page 510
Gravel or crushed stone
Drain field
Vent pipe
Perforated pipe
63Figure 22-16 Page 511
Secondary
Primary
Grit chamber
Chlorine disinfection tank
Bar screen
Settling tank
Aeration tank
Settling tank
To river, lake, or ocean
Raw sewage from sewers
(kills bacteria)
Sludge
Activated sludge
Air pump
Sludge digester
Sludge drying bed
Disposed of in landfill or ocean or applied to
cropland, pasture, or rangeland
64Sludge
- Slimy mixture of bacteria-laden solids toxic
chemicals metals from industrial household
waste - Used to make compost for soil conditioning
- Biosolids- used to fertilize farmlands, forests,
golf courses, cemeteries, parkland, highway
medians, degraded land
65Sludge as Fertilizer
- Must remove harmful bacteria, other pathogens,
toxic chemicals - Removal is expensive rarely done
66Toxic / Hazardous Waste
- Preventing it from reaching sewage treatment
plant - Require industries businesses to remove toxic
hazardous wastes from waste water - Switch to waterless composting toilet systems
67Wetlands
- Sewage goes into sedimentation tanks (solids
settle out as sludge) - Liquid is pumped into oxidation ponds where
bacteria breaks down remaining wastes - Water released 1 month later into artificial
marsh (plants bacteria carry out further
filtration cleansing)
68Wastewater Garden
- Small, low-tech inexpensive artificial wetland
- Removes 99.9 of fecal coliform bacteria
- Removes 80 of nitrates phosphates from
incoming sewage
69Figure 22-18 Page 513
(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.
Sewage
Treated water
Wetland type plants
Wetland type plants
45 centimeter layer of limestone gravel coated
with decomposing bacteria
First concrete pool
Second concrete pool
(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.
70U.S. Reduction of Water Pollution
- Increased to 94 of community water systems met
federal health standards - Fishable/swimmable areas increased to 60
- Topsoil loss cut by 1 billion tons
- Sewage treatment plants increased service to
74 - Annual wetland loss decreased to 80
71- - 45 of lakes 40 of streams were too polluted
for fishing or swimming - - Only 19 of streams, 43 of lakes, 36 of
estuaries have been tested for water quality - - 70 of rivers are polluted by animal waste from
hog, poultry, cattle feedlots meat processing
facilities
72- - Fish caught in 25 of lakes are unsafe to eat
due to pesticides, mercury, or other toxic
substances
73Strengthening CWA
- Increased funding authority to control nonpoint
sources of pollution - Upgrade computer system for monitoring compliance
with the law - Strengthening programs to prevent control toxic
water pollution - More integrated watershed air shed planning to
protect groundwater surface water from
contamination
74Opposition
- CWA is too restrictive costly
- Curb on right of landowner to fill in wetlands
- Landowners want compensation for property value
losses
75Water Purification
- Stored in reservoir for several days (increases
DO level suspended matter settles) - Water is pumped to purification plant for
filtration chlorination
76Vulnerability to Terrorist Attacks
- Fear of added chemicals or biological agents
- Hard to protect due to large numbers of
reservoirs, vast network of purification plants
distribution systems, accessibility of water
systems through fire hydrants service
connections
77Purification in Developing Countries
- Exposing water in clear plastic bottle to intense
sunlight (heat UV will kill infectious microbes
in 3 hrs) - Strips of cloth for filtering cholera-producing
bacteria - Add small amount of chlorine-disinfectant
solution to plastic or clay storage containers
with narrow mouth, cap, spigot
78Protecting Drinking Water
- 54 countries have standards for safe drinking
water - Safe Water Drinking Act- requires EPA to
establish national drinking water standards
(maximum contaminant levels) for pollutants with
adverse effects on human health - Private wells are exempt
79Success of Efforts
- Most of the 54 countries are in North America
Europe - CWA laws do not exist or are not enforces in
developing countries
80Strengthening U.S. SDWA
- Combine water treatment systems that serve fewer
than 3,300 people - Strengthen enforce public notification
requirements about violations of standards - Banning all toxic lead in pipes, faucets,
fixtures
81Weakening SWDA
- Eliminate national tests of drinking water
public notification requirements about violations
of standards - Give water systems permanent right to violate
standards if it cannot afford to comply
82- Eliminate requirement that water systems remove
cancer-causing contaminants - Reduce EPA budget for enforcing CWA
83Bottled Water
- 240-10,000X more expensive than tap water
- ¼ of bottled water is tap water
- Bacteria contaminates 1/3
- Various potentially harmful organic chemicals
contaminate 1/5 - 1.5 million tons (bottles) trashed globally
84- Manufacturing plastic water bottles releases
toxic gases liquids (greenhouse gases) - Some tap water is too polluted to drink
85Solutions
Water Pollution
- Prevent groundwater contamination
- Greatly reduce nonpoint runoff
- Reuse treated wastewater for irrigation
- Find substitutes for toxic pollutants
- Work with nature to treat sewage
- Practice four R's of resource use (refuse,
reduce, recycle, reuse) - Reduce resource waste
- Reduce air pollution
- Reduce poverty
- Reduce birth rates
Figure 22-19Page 516
86What Can You Do?
Water Pollution
- Fertilize your garden and yard plants with manure
or compost instead of commercial inorganic
fertilizer. - Minimize your use of pesticides.
- Never apply fertilizer or pesticides near a body
of water. - Grow or buy organic foods.
- Compost your food wastes.
- Do not use water fresheners in toilets.
- Do not flush unwanted medicines down the toilet.
- Do not pour pesticides, paints, solvents, oil,
antifreeze, or other products containing harmful
chemicals down the drain or onto the ground.
Figure 22-20Page 516