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Water and Water Pollution

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Title: Water and Water Pollution


1
Water and Water Pollution
  • Chapter 11
  • Brian W, Kate H, Amanda K

2
Key Concepts
  • Why is water so important?
  • How much water is available?
  • How much water are we using?
  • What causes water shortages and what can be done?
  • What causes floods and how can they be avoided?
  • Sources, types, and risks of water pollution
  • Preventing and reducing water pollution
  • Sustainable use of water resources

3
Water Conflicts in the Middle East
  • Water shortages
  • Nile River
  • Jordan Basin- water short
  • Tigris and Euphrates rivers
  • Jordan, Syria, Palestine, and Israel competing
    for the water
  • Peacefully solving the problems

Fig. 11-1, p. 236
4
Earths Water Budget
All water
Fresh water
Readily accessible fresh water
Groundwater 0.592
Biota 0.0001
Rivers 0.0001
Lakes 0.007
0.014
Fresh water 2.6
Atmospheric water vapor 0.001
Oceans and saline lakes 97.4
Ice caps and glaciers 1.984
Soil moisture 0.005
Fig. 11-2, p. 238
5
Groundwater
  • Zone of saturation- under the ground, spaces
    between rocks and soil that fill with water
  • Water table- top of zone of saturation, falls in
    dry weather, rises in wet weather
  • Aquifers- porous, saturated layers of sand,
    gravel, or bedrock through which groundwater
    flows
  • Natural recharge- precipitation percolates
    downward through soil and rock which replenishes
    aquifers naturally

6
Groundwater Systems
Unconfined Aquifer Recharge Area
Evaporation and transpiration
Evaporation
Precipitation
Confined Recharge Area
Runoff
Flowing artesian well
Recharge Unconfined Aquifer
Stream
Well requiring a pump
Water table
Lake
Infiltration
Infiltration
Unconfined aquifer
Less permeable material such as clay
Confined aquifer
Confining impermeable rock layer
Fig. 11-3, p. 239
7
Use of Water Resources
  • Runoff use about 54
  • Freshwater use-
  • 20 - industry
  • 10 - cities and residents
  • 70 - irrigation of 1/5 of the worlds cropland
    (40 of world food)
  • Domestic, agricultural, and industrial use
  • US freshwater resources- more than enough
    freshwater resources. East- energy, cooling and
    manufacturing. West- irrigation

8
Annual Precipitation and Water-deficit Regions of
the Continental US
Fig. 11-4a, p. 240
9
Water Hot Spots in Western States
Wash.
N.D.
Montana
Oregon
S.D.
Idaho
Wyoming
Neb.
Nevada
Colo.
Utah
Kansas
California
Oak.
N.M.
Texas
Highly likely conflict potential
Substantial conflict potential
Moderate conflict potential
Unmet rural water needs
Fig. 11-5, p. 240
10
Freshwater Shortages
  • Causes of water scarcity dry climate and too
    many people
  • Stresses on worlds major river systems
  • 1 of 6 people have no regular access to clean
    water
  • Poverty hinders access to water
  • Hydrological poverty

11
Stress on Worlds River Basins
Europe
North America
Asia
Africa
South America
Australia
Stress
High
None
Fig. 11-6, p. 241
12
Hydrological Poverty
  • An increasing number of governments are gaining
    ownership of public water by hiring private
    companies to manage them.
  • In Cochabamba, Bolivia, 60 of the water is
    being lost through leaking pipes.
  • Two potential problems of privatized water
    systems
  • Since they have an incentive to sell as much
    water as they can, they dont conserve well.
  • Because of lack of money to pay water bills, poor
    will continue to be left out

Fig. 11-7, p. 241
13
Increasing Freshwater Supplies
  • Building damns
  • Bringing in water from somewhere else
  • Withdrawing groundwater
  • Converting salt water to freshwater
    (desalinization)
  • Wasting less water
  • Importing food

14
Tradeoffs of Large Dams and Reservoirs
Large losses of water through evaporation
Flooded land destroys forests or cropland
and displaces people
Downstream cropland and estuaries are deprived of
nutrient-rich silt
Migration and spawning of some fish are disrupted
Provides water for year-round irrigation
of cropland
Reservoir is useful for recreation and fishing
Can produce cheap electricity (hydropower)
Downstream flooding is reduced
Fig. 11-8, p. 243
15
Ecological Services of Rivers
N a t u r a l C a p i t a l
Ecological Services of Rivers
Deliver nutrients to sea to help
sustain coastal fisheries Deposit silt that
maintains deltas Purify water Renew and
renourish wetlands Provide habitats for
wildlife
Fig. 11-9, p. 243
16
California Water Project and Central Arizona
Project
CALIFORNIA
NEVADA
Shasta Lake
UTAH
Oroville Dam and Reservoir
Sacramento River
Lake Tahoe
Feather River
North Bay Aqueduct
Sacramento
San Francisco
Hoover Dam and Reservoir (Lake Mead)
South Bay Aqueduct
Fresno
San Joaquin Valley
Colorado River
San Luis Dam and Reservoir
Los Angeles Aqueduct
California Aqueduct
ARIZONA
Colorado River Aqueduct
Santa Barbara
Central Arizona Project
Los Angeles
Phoenix
Salton Sea
San Diego
Tucson
Fig. 11-10, p. 244
MEXICO
17
Aral Sea Disaster
  • Large-scale water transfers in dry central Asia
  • Salinity
  • Wetland destruction and wildlife
  • Fish extinctions and fishing
  • Wind-blown salt
  • Water pollution
  • Climatic changes
  • Restoration efforts

18
Shrinking Aral Sea
Fig. 11-11, p. 245
19
Stranded Ship at the Aral Sea
Fig. 11-12, p. 245
20
Tradeoffs of Withdrawing Groundwater
Trade-Offs
Withdrawing Groundwater
Advantages
Disadvantages
Good source of water for drinking and
irrigation Available year-round Exists almost
everywhere Renewable if not over- pumped or
contaminated No evaporation losses Cheaper to
extract than most surface waters
Aquifier depletion from over- pumping Sinking of
land (subsidence) when water removed Polluted
aquifiers unusable for decades or
centuries Saltwater intrusion into drinking
water supplies near coastal areas Reduced water
flows into streams, lakes, estuaries, and
wetlands Increased cost, energy use, and
contamination from deeper wells
Fig. 11-13, p. 246
21
Aquifer Depletion
Groundwater Overdrafts
High
Moderate
Minor or none
Fig. 11-14, p. 246
22
Groundwater Depletion
Solutions
Groundwater Depletion
Prevention
Control
Waste less water Subsidize water conservation Ba
n new wells in aquifiers near surface
waters Buy and retire ground- water withdrawal
rights in critical areas Do not grow
water- intensive crops in dry areas Reduce
birth rates
Raise price of water to discourage
waste Tax water pumped from Wells near
surface water Set and enforce minimum
stream flow levels
Fig. 11-16, p. 247
23
Saltwater Intrusion into Coastal Water Wells-
groundwater depletion
Well contaminated with saltwater
Major irrigation well
Water table
Sea Level
Saltwater
Fresh groundwater aquifer
Seafloor
Interface
Saltwater Intrusion
Interface
Normal Interface
Fig. 11-15, p. 247
24
Desalination
  • Removal of salts from ocean or brackish waters to
    produce useable water
  • Distillation method-heating salt water until it
    evaporates, leaves behind salts in solid form,
    and condenses as fresh water
  • Reverse osmosis method- pumping salt water at
    high pressure through a thin membrane with pores
    that allow water molecules, but not most
    dissolved salts, to pass through. High pressure
    is used to push fresh water out of salt water
  • Used in 120 countries
  • Major problems high cost and a lot of brine
    wastes (contains salt and other minerals)
  • Research is needed
  • Significant desalination is practical only for
    wealthy and water-short countries and cities that
    can afford its high costs

25
Reducing Water Waste
  • Benefits of water conservation- Reduce leakage
    and save water, Improve irrigation
  • Increase water prices (we charge too little), no
    government subsidies (provide irrigation water,
    electricity, and diesel fuel for farmers at below
    market prices), and water waste
  • Using less water in homes and businesses

26
Major Types of Irrigation Systems
Drip Irrigation (efficiency 90-95) Above- or
below-ground pipes or tubes deliver water to
individual plant roots.
Gravity Flow (efficiency 60 and 80 with surge
valves) Water usually comes from an aqueduct
system or a nearby river.
Center Pivot (efficiency 80 with low-pressure
sprinkler and 9095 with LEPA sprinkler) Water
usually pumped from underground and sprayed from
mobile boom with sprinklers.
Fig. 11-17, p. 249
27
Reducing Irrigation Water Waste
Solutions
Reducing Irrigation Water Waste
  • Lining canals bring water to irrigation ditches
  • Leveling fields with lasers
  • Irrigating at night to reduce evaporation
  • Using soil and satellite sensorsand computer
    systems to monitor soil moisture and add water
    only when necessary
  • Polyculture
  • Organic Farming
  • Growing water-efficient crops using
    drought-resistant and salt tolerant crops
    varieties
  • Irrigating with treated urban waste water
  • Importing water-intensive crops and meat

Fig. 11-18, p. 250
28
Reducing Water Waste
Solutions
Reducing Water Waste
  • Redesign manufacturing processes
  • Landscape yards with plants that require little
    water
  • Use drip irrigation
  • Fix water leaks
  • Use water meters and charge for all municipal
    water use
  • Use waterless composting toilets
  • Require water conservation in water-short cities
  • Use water-saving toilets, showerheads, and
    front-loading clothes washers
  • Collect and reuse household water to irrigate
    lawns and nonedible plants
  • Purify and reuse water for houses, apartments,
    and office buildings

Fig. 11-19, p. 250
29
Using Water More Sustainably
  • Blue revolution-
  • Using technology to irrigate crops more
    efficiently and to save water in industries and
    homes
  • Economic and political policies to remove
    subsidies that cause water to be under priced and
    wasted, while guaranteeing low prices for
    low-income consumers
  • Switch to new waste-treatment systems
  • Leave enough water in nature
  • Help by using and wasting less water
  • Cut waste
  • Raise water prices
  • Drier waste treatment
  • Preserve forests
  • Slow population growth

30
Sustainable Water Use
Solutions
Sustainable Water Use
  • Not depleting aquifers
  • Preserving ecological health of aquatic systems
  • Preserving water quality
  • Integrated watershed management
  • Agreements among regions and countries sharing
    surface water resources
  • Outside party mediation of water disputes between
    nations
  • Marketing of water rights
  • Raising water prices
  • Wasting less water
  • Decreasing government subsides for supplying
    water
  • Increasing government subsides for reducing water
    waste
  • Slowing population growth

Fig. 11-20, p. 251
31
What Can We Do?
What Can You Do?
Water Use and Waste
  • Use water-saving toilets, showerheads, and faucet
    aerators
  • Shower instead of taking baths, and take short
    showers.
  • Repair water leaks.
  • Turn off sink faucets while brushing teeth,
    shaving, or washing.
  • Wash only full loads of clothes or use the lowest
    possible water-level setting for smaller loads.
  • Wash a car from a bucket of soapy water, and use
    the hose for rinsing only.
  • If you use a commercial car wash, try to find one
    that recycles its water.
  • Replace your lawn with native plants that need
    little if any watering.
  • Water lawns and garden in the early morning or
    evening.
  • Use drip irrigation and mulch for gardens and
    flowerbeds.
  • Use recycled (gray) water for watering lawns and
    houseplants and for washing cars.

Fig. 11-21, p. 251
32
Benefits of Floodplains
  • Floodplain- a flood happens when water in a
    stream overflows its normal channel and spills
    into the adjacent area
  • Highly productive wetlands
  • Provide natural flood and erosion control
  • Maintain high water quality
  • Recharge groundwater
  • Fertile soils
  • Nearby rivers for use and recreation
  • Flatlands for urbanization and farming

33
Dangers of Floodplains and Floods
  • Deadly and destructive (considered natural
    disaster)
  • Human activities worsen floods
  • Failing dams and water diversion
  • Bangladesh- One of the worlds most densely
    populated countries. Due to overpopulation in
    the Himalayan watershed, great floods are now
    occurring every 4 years instead of every 50 years
    because of deforestation, overgrazing, and
    unsustainable farming.

34
Before and During a Flood in St. Louis, Missouri
This image shows the negative effects of living
on a flood plain.
Fig. 11-22, p. 252
35
Flooding After Deforestation of a Hillside
Fig. 11-23, p. 253
36
Reducing Flood Risks
  • Channelization- straighten and deepen streams
  • Levees (floodwalls)- contain and speed up stream
    flow
  • Dams- storing water
  • Protect and restore wetlands- natural flood
    control
  • Identify and manage flood-prone areas
  • Precautionary approach- to think carefully about
    where we live

37
Water Pollution
  • What is water pollution? Any chemical,
    biological, or physical change in water quality
    that harms living organisms or makes water
    unsuitable for desired uses
  • Point sources- discharge pollutants at specific
    locations
  • Nonpoint sources- scattered and diffuse and cant
    be traced to any single site of discharge
  • Is the water safe to drink? 95 of people in
    developed countries have access to safe drinking
    water. According to the WHO, 1 in every 5 people
    on Earth dont have access to clean drinking
    water. Every day 9300 people die from infectious
    diseases from contaminated water.

38
Polluted Streams
  • Factors influencing stream recovery from
    pollution
  • Oxygen sag curve
  • Importance of wastewater treatment plants- so you
    dont put contaminated water back into streams,
    lakes, and bays
  • Improvements in quality of US streams- water
    pollution control laws in 1970 increased the
    amount of wastewater treatment plants in the US
  • Cuyahoga River of Ohio- Caught fire twice in a
    ten year span. Resulted in new laws prohibiting
    the discharge of industrial wastes into rivers
  • Effect of regulations in US- cleaner streams,
    loss of pollution
  • Problems with nonpoint, accidental and illegal
    releases- cant really stop it easily
  • Problems in developing countries- Half of the
    worlds 500 rivers are heavily polluted, most of
    them going through developing countries. Only
    10 of sewage from Chinese cities is treated.

39
Pollution in Streams (Oxygen sag curve)
Normal 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)
Clean Zone
Biological oxygen demand
Recovery Zone
Septic Zone
Decomposition Zone
Clean Zone
Fig. 11-24, p. 256
40
Lake Pollution
  • Dilution less effective than with streams
  • Stratification (layers in the lake) and
    relatively little flow hinder rapid dilution of
    pollutants
  • Lakes more vulnerable to pollutants than streams
  • How pollutants enter lakes- runoff from
    watersheds, farmland, animal feedlots, urban
    areas, mining sites, sewage
  • Eutrophication name given to the natural
    nutrient enrichment of lakes mostly from runoff
    of plant nutrients such as nitrates and
    phosphates from surrounding land. In hot weather
    or drought the nutrient overload produces algae,
    creating green lakes.
  • Oligotrophic lake- low in nutrients (clear)
  • Eutrophic lake- green lakes
  • Cultural eutrophication- Human activities
    accelerate the input of plant nutrients.
  • Preventing or removing eutrophication
  • Advanced waste treatment to remove nitrates and
    phosphates
  • Ban or limit the use of phosphates in household
    detergents
  • Employ soil conservation and land use control to
    reduce nutrient runoff

41
Oligotrophic and Eutrophic Lakes
Oligotrophic (clear lakes)
Eutrophic (green lakes)
Fig. 11-25, p. 257
42
Groundwater Pollution Causes and Persistence
  • Sources of groundwater pollution- oil spills,
    paint thinners, sewage, hazardous wastes
    injection wells, waste lagoons, landfills
  • Slow flowing Groundwater flows so slowly (1 foot
    per day) that contaminants are not diluted and
    dispersed effectively.
  • Consequences of lower dissolved oxygen-
    dissolved oxygen helps decompose many
    contaminants
  • Fewer bacteria to decompose wastes
  • Cooler temperatures slow down chemical reactions
  • Degradable and nondegradable wastes in
    groundwater

43
Groundwater Pollution
Polluted air
Hazardous waste injection well
Pesticides and fertilizers
De-icing road salt
Coal strip mine runoff
Buried gasoline and solvent tank
Pumping well
Gasoline station
Water pumping well
Cesspool septic tank
Waste lagoon
Sewer
Landfill
Leakage from faulty casing
Accidental spills
Discharge
Unconfined freshwater aquifer
Confined aquifer
Confined freshwater aquifer
Groundwater flow
Fig. 11-26, p. 258
44
Extent of Groundwater Pollution
  • Not much is known about groundwater pollution
  • Organic contaminants, including fuel leaks
  • Arsenic- contaminates drinking water that comes
    from underground wells
  • Protecting groundwater Prevention is best

45
Preventing and Cleaning Up Pollution in
Groundwater
Solutions
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
Fig. 11-27, p. 259
46
Ocean Pollution
  • How much pollution can oceans tolerate? Oceans
    can dilute, disperse, and degrade large amounts
    of pollutants, especially in deep ocean areas
  • Ocean dumping controversies
  • Some scientists think that it is best to dump
    pollutants in deep water instead of burying them.
  • We dont know enough about the ocean so we may
    not know the harmful effects in the long run

47
Coastal Water Pollution
Urban sprawl Bacteria and viruses from sewers and
septic tanks contaminate shellfish beds and close
beaches runoff of fertilization from lawns adds
nitrogen and phosphorus.
Cities Toxic metals and oil from streets
and parking lots pollute waters sewage adds
nitrogen and phosphorus.
Industry Nitrogen oxides from autos and
smokestacks toxic chemicals, and heavy metals in
effluents flow into bays and estuaries.
Construction sites Sediments are washed into
waterways, choking fish and plants,
clouding waters, and blocking sunlight.
Farms Run off of pesticides, manure, and
fertilizers adds toxins and excess nitrogen and
phosphorus.
Red tides Excess nitrogen causes explosive growth
of toxic microscopic algae, poisoning fish and
marine mammals.
Closed shellfish beds
Closed beach
Oxygen-depleted zone
Toxic sediments Chemicals and toxic
metals contaminate shellfish beds, kill spawning
fish, and accumulate in the tissues of bottom
feeders.
Healthy zone Clear, oxygen-rich waters promote
growth of plankton and sea grasses, and support
fish.
Oxygen-depleted zone Sedimentation and algae
overgrowth reduce sunlight, kill beneficial sea
grasses, use up oxygen, and degrade habitat.
Fig. 11-28, p. 260
48
Oxygen-depleted Water in the Gulf of Mexico
Mississippi River Basin
Ohio River
Mississippi River
Missouri River
LOUISIANA
Mississippi River
Depleted Oxygen
Gulf of Mexico
Fig. 11-29, p. 261
49
Chesapeake Bay
  • Largest US estuary
  • Pollution sink
  • Oxygen depletion
  • Chesapeake Bay Program

Fig. 11-30, p. 261
50
Effects of Oil on Ocean Life
  • Crude and refined petroleum- most oil pollution
    comes from human activities on land
  • Tanker accidents and blowouts
  • Exxon Valdez- tanker that spilled oil into
    Alaskas Prince William Sound (waterway)
  • Volatile hydrocarbons kill larvae- hydrocarbons
    immediately kill aquatic organisms
  • Tar-like globs coat birds and marine mammals
  • Oil destroys insulation and buoyancy
  • Heavy oil sinks and kills bottom organisms
  • Coral reefs die
  • Slow recovery
  • Oil slicks ruin beaches

51
Preventing and Cleaning Up Pollution in Coastal
Waters
Solutions
Coastal Water Pollution
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
Fig. 11-31, p. 263
52
Preventing Nonpoint Source Pollution
  • Mostly agricultural wastes
  • Use vegetation to reduce soil erosion
  • Reduce fertilizer use
  • Use plant buffer zones around fields
  • Integrated pest management Only use pesticides
    when necessary
  • Use plant buffers around animal feedlots
  • Keep feedlots away from slopes, surface water and
    flood zones

53
Laws for Reducing Point Source Pollution
  • Clean Water Act (1972)
  • Sets standards for allowed levels of key water
    pollutants and requires polluters to get permits
  • Water Quality Act
  • Another effort to clean water in the US
  • Discharge trading controversies
  • Allow buildup of pollutants in areas where
    credits are bought

54
Sewage Treatment Systems
  • Sewage treatment in rural and suburban areas
  • Septic tanks
  • Primary (physical) sewage treatment
  • Secondary (biological) sewage treatment
  • Urban sewage treatment (Clean Water Act)
  • Sewage treatment facilities in many cities fail
    to meet federal standards
  • Bleaching and disinfection- last step of water
    treatment
  • Disinfectants chlorine, ozone, and ultraviolet
    radiation

55
Typical Septic Tank System
Septic tank with manhole (for cleanout)
Household wastewater
Nonperforated pipe
Distribution box (optional)
Gravel or crushed stone
Drain field
Vent pipe
Perforated pipe
Fig. 11-32, p. 264
56
Primary and Secondary Sewage Treatment
Primary
Secondary
Chlorine disinfection tank
Bar screen
Grit chamber
Settling tank
Aeration tank
Settling tank
To river, lake, or ocean
Sludge
Activated sludge
(kills bacteria)
Raw sewage from sewers
Air pump
Sludge digester
Disposed of in landfill or ocean or applied to
cropland, pasture, or rangeland
Sludge drying bed
Fig. 11-33, p. 265
57
Improving Sewage Treatment
  • Systems that exclude hazardous wastes
  • Non-hazardous substitutes
  • Composting toilet systems
  • Working with nature to treat sewage
  • Using wetlands to treat sewage

58
Ecological Wastewater Treatment
Plants clean the wastewater
Fig. 11-34, p. 265
59
Reducing Water Pollution from Point Sources in
the US
  • Improvements
  • Bad news

60
Should the Clean Water Act be Strengthened?
  • Yes environmentalists
  • No farmers, libertarians, manufacturers, and
    developers
  • State and local officials want more discretion
  • How Would You Vote exercise
  • http//biology.brookscole.com/miller11

61
Drinking Water Quality
  • Purification of urban drinking water- allowing
    water to sit for several days. Increases taste
    and clarity and allows matter to settle on the
    bottom
  • Purification of drinking water in developing
    countries- households receive strips of cloth for
    filtering cholera producing bacteria. Villages
    that have done this have cut the cholera cases in
    half
  • Bottled water- studies have shown that US bottled
    water is 240 times to 10000 times more expensive
    than tap water. 25 of bottled water is tap
    water.

62
Reducing Water Pollution
Solutions
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

Fig. 11-35, p. 267
63
What Can We Do?
What 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.

Fig. 11-36, p. 268
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