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Clean Water Life Depends on It!
"Pure water is the best of gifts that man to
man can bring"
- Spectator, July 30, 1920
What's in a glass, a sink, a river full of water?... A refreshing
drink... a cleansing wash... an invigorating swim... a home for plants,
insects, fish, birds and mammals. It all depends on the water
quality.
We tend to think of water in terms of a particular purpose: is the
quality of the water good enough for the use we want to make of it? Water
fit for own use may be unfit for another. We may, for instance, trust the
quality of lake water enough to swim in it, but not enough to drink it.
Along the same lines, drinking water can be used for irrigation, but water
used for irrigation may not meet drinking water standards. It is the
quality of the water which determines its uses.
Scientists, on the other hand, are interested in other aspects of water
quality. To them quality is determined by the kinds and amounts of
substances dissolved and suspended in the water and what those substances
do to inhabitants of the ecosystem. It is the concentrations of these
substances that determine the water quality and its suitability for
particular purposes.
Drinking water, for example, is regulated by guidelines stringent
enough to protect human health. Lack of such guidelines can lead to a
variety of health problems. It has been estimated, for example, that
contaminated water and poor sanitation cause 30 000 deaths
around the world daily the equivalent of 100 jumbo jets
crashing every day!
Water is the lifeblood of the environment, essential to the survival of
all living things plant, animal and human and we must do
everything possible to maintain its quality for today and the future.
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The Great Lakes: chemical hot spot
Over 360 chemical compounds have been
identified in the Great lakes. Many are persistent toxic
chemicals alkylated lead, benzo(a)pyrene, DDT, mercury and
mirex potentially dangerous to humans and already destructive
to the aquatic ecosystems.
For example, various species of fish now suffer
from tumours and lesions, and their reproductive capacities are
decreasing. Populations of fish-consuming birds and mammals also
seem to be on the decline. Of the ten most highly valued species of
fish in Lake Ontario, seven have now almost totally
vanished. |
Canada: a water paradise?
Here in Canada we are fortunate. We have extensive supplies of water.
Our pristine rivers and lakes filled explorers and settlers with a sense
of majesty and awe. Today, they continue to impress Canadians and visitors
alike. Yet under the pressures of human development, many of these waters
are losing their un-spoiled quality.
It is no wonder. We dispose of human wastes, animal wastes and chemical
substances into the environment at such a rate that even some of the
largest lakes and river systems the Great Lakes and the St.
Lawrence River, for example are having serious difficulty cleansing
themselves and sustaining life.
What determines water quality?
The water of even the healthiest rivers and lakes is not absolutely
pure. All water (even if it is distilled) contains many naturally
occurring substances mainly bicarbonates, sulphates, sodium,
chlorides, calcium, magnesium, and potassium (total dissolved solids).
They reach the surface and groundwater from:
- soil, geologic formations and terrain in the catchment area (river
basin);
- surrounding vegetation and wildlife;
- precipitation and runoff from adjacent land;
- biological, physical and chemical processes in the water;
- human activities in the region.
Total dissolved solids in selected Canadian rivers: 
Aquatic ecosystems
In nature nothing exists alone. Living things relate to each other as
well as to their non-living, but supporting, environments. These complex
relationships are called ecosystems. Each body of water is a
delicately balanced ecosystem in continuous interaction with the
surrounding air and land.
Whatever occurs on the land and in the air also affects the water. If a
substance enters a river or lake, the water can purify itself
biologically but only to a degree. Whether it is in the smallest
stream or lake or even in the mighty oceans the water can
absorb only so much. It reaches a point where the natural cleaning
processes can no longer cope.
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How does water clean itself?
Water is purified in large part by the routine
actions of living organisms. Energy from sunlight drives the process
of photosynthesis in aquatic plants, which produces oxygen to break
down some of the organic material such as plant and animal waste.
This decomposition produces the carbon dioxide, nutrients and other
substances needed by plants and animals living in the water. The
purification cycle continues when these plants and animals die and
the bacteria decompose them, providing new generations of organisms
with nourishment.
Unfortunately, there are many toxic substances
which are affected only slowly, or not at all, by this and other
processes. These are called persistent (see Water
quality pollutants) and are of great environmental
concern. |
How do we measure water quality?
To identify the substances present in a stream or lake, scientists
collect samples of the water, of living organisms, and of suspended and
bottom sediments. Technicians then analyze these samples in a laboratory
with specialized instruments and procedures. Certain measurements such as
temperature, dissolved oxygen, turbidity and conductivity can be taken in
the field with portable equipment.
Today's analytical laboratory instruments with such high-tech
names as "plasma emission spectrometer" (for analysing metals) and "gas
chromatograph-mass spectrometer" (for analysing pesticides, PCBs dioxins,
and other organic compounds) bear little resemblance to the
test-tube and gas burner laboratories of the 1950s.
Nowadays the analysis of water and sediment samples detects more
substances than a decade ago, partly because there are more substances
present in water, but also because of improved analytical instruments and
consequently lower detection limits. State-of-the-art analytical
instruments can detect down to one part per trillion of some
substances comparable to tracing one thousandth of a teaspoon of
salt dissolved in an olympic-size swimming pool.
The pH scale:
Human health and water quality
In Canada we are lucky to have plentiful supplies of good drinking
water sources. Water-related illnesses typhoid fever, cholera,
dysentery are almost unknown in this country today. Waste and
wastewater treatment, the development and enforcement of drinking water
guidelines, public health practices and education all have resulted
in a decrease in water related illnesses in Canada. Developing nations are
less fortunate: 80% of their diseases are water-related.
The price Canadians must pay to prevent water-borne disease is constant
vigilance against bacterial contamination. Periodic beach closures and
local epidemics are evidence that the battle is never won. These problems
underscore the need for maintaining strict control over water quality and
for improving water and wastewater treatment.
Of serious concern today are the toxic chemicals that enter our waters
from many different sources, including industry, agriculture and the home.
Little is known about the effects of these toxic substances on human
health; often the effects do not become noticeable for long periods of
time, and it is difficult to distinguish them from the effects of other
factors that impact on our day-to-day life (e.g., nutrition, stress, air
quality). Much more remains to be done to control toxic chemical
pollution. Meanwhile, we can all contribute to the prevention of water
pollution by not abusing the water or the land. (See What
can I do to improve water quality?)
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A sampling of water quality facts
- Approximately 57% of Canadians are served by wastewater
treatment plants, compared with 74% of Americans, 86.5% of
Germans, and 99% of Swedes.
- In developing nations, 80% of diseases are water-related.
- Of all Canadians, 26% rely on groundwater for domestic use.
- One drop of oil can render up to 25 litres of water unfit
for drinking.
- One gram of 2,4-D (a common household herbicide) can
contaminate ten million litres of drinking water.
- One gram of PCBs can make up to one billion litres of water
unsuitable for freshwater aquatic life.
- One gram of lead in 20 000 litres of water makes it
unfit for drinking. Older homes often contain plumbing made of
lead or soldered in lead, which can then leach into water.
- The nitrates in fertilizers promote excessive growth of algae
and larger aquatic plants, causing offensive algal blooms and
driving out sport fish.
- Methane gas can often be seen bubbling up from the bottom of
ponds; it is produced by the decomposition of dead plants and
animals in the mud.
- Calcium and magnesium both essential elements for
man account for most water hardness. Death rates for
certain types of cardiovascular disease have been found to be
higher in soft water areas than in hard water areas in many parts
of the world.
- Copper is another essential element for optimal
absorption and metabolism of iron and for bone formation
and fairly common in natural water. More than one milligram per
litre may make water unpalatable.
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The pollution problem
It is easy to dispose of waste by dumping it into a river or lake. In
large or small amounts, dumped intentionally or accidentally, it may be
carried away by the current, but will never disappear. It will reappear
downstream, sometimes in changed form, or just diluted. Freshwater bodies
have a great ability to break down some waste materials, but not in the
quantities discarded by today's society. This overload that results,
called pollution, eventually puts the ecosystem out of balance.
Sometimes nature itself can produce these imbalances. In some cases,
the natural composition of the water makes it unfit for certain uses:
e.g., water flowing in the highly saline terrain of the prairies or
gushing from highly mineralized springs in some parts of the country
cannot sustain fish populations.
But most often our waterways are being polluted by municipal,
agricultural and industrial wastes, including many toxic synthetic
chemicals which cannot be broken down at all by natural processes. Even in
tiny amounts, some of these substances can cause serious harm.
The Great Lakes, the Fraser River, and the St. Lawrence River are
and continue to be seriously contaminated by such toxic chemicals.
We have polluted our way to wealth... at the
expense of the environment.
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Toxic chemicals: the
legacy of a chemical society
We are a "chemical" society, using hundreds of
chemicals in our normal daily activities: washing, eating,
house-cleaning, tending the lawn and garden, and driving. Of the
almost 10 million chemicals known today, approximately
100 000 chemicals are used commercially. Over
10 000 new chemicals are created each week.
Most toxic chemicals are discharged directly into
our waterways as waste, but many also enter the water after everyday
use in the home, agriculture and industry. They constantly change
the chemical composition of our waters. One way is seepage: the
chemicals soak through the earth into the groundwater from waste
disposal sites and agricultural lands, for example. Another way is
runoff: the chemicals are washed into bodies of water from the land
where they were used or spilled, or from the air into which they
were emitted.
The chemicals can cause problems with the taste,
odour and colour in water. Fish and wildlife can experience reduced
fertility, generic deformities immune system damage, increased
incidence of tumours, and death.
Many of the chemicals that enter the water are,
even in minute amounts, toxic to human, plant and animal life.
Pesticides, PCBs, and PCPs (polychlorinated phenols) are typical
examples. Pesticides are used in agriculture, forestry and homes.
PCBs although no longer used in new installations, are still found
as insulators in older electrical transformers, and PCPs can be
found in wood preservatives. The very qualities which make them
desirable for use toxicity and persistence, for
instance make them so harmful to the environment.
Toxic substances in the aquatic
environment: |
The effects of pollution
Pollution is not always visible. A river or lake may seem clean, but
still be polluted. In groundwater, on which over one quarter of all
Canadians rely for their water supply, pollution is especially difficult
to discern. Nor are the effects of pollution necessarily immediate; they
may take years to appear.
When pollution makes water unsuitable for drinking, recreation,
agriculture and industry, it eventually also diminishes the aesthetic
quality of lakes and rivers. Even more seriously, when contaminated water
destroys aquatic life and reduces its reproductive abilities, it
eventually menaces human health. Nobody escapes the effects of water
pollution.
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Water quality
pollutants
Non-persistent (degradable)
- domestic sewage
- fertilizers
- some industrial wastes
These compounds can be broken down by chemical
reactions or by natural bacteria into simple, non-polluting
substances such as carbon dioxide and nitrogen. The process can lead
to low oxygen levels and eutrophication if the pollution load is
high. But this damage is reversible.
Persistent (degrade slowly)
- some pesticides (e.g. DDT, dieldrin)
- some leachate components from landfill sites (municipal,
industrial)
- petroleum and petroleum products
- PCBs, dioxins, polyaromatic hydrocarbons (PAHs)
- radioactive materials such as strontium-90, cesium-137,
radium-226, and uranium
- metals such as lead, mercury, cadmium
This is the most rapidly growing type of pollution
and includes substances that degrade very slowly or cannot be broken
down at all; they may remain in the aquatic environment for years or
longer periods of time. The damage they cause is either irreversible
or reparable only over decades or centuries.
Other
- warm water from cooling towers (thermal pollution)
- floating debris
- garbage
- foam
These are examples not of chemical pollution, but
of physical pollution which interferes mainly with the usability
and/or aesthetic appeal of the water. In certain cases, thermal
pollution can kill fish. |
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The long-range transport of airborne
pollutants: what goes up must come down
On a daily basis, human activities
industrial, agricultural and residential cause vast
quantities of natural and synthetic chemicals to be emitted into the
atmosphere. Once released, the substances are dispersed throughout
the globe by air currents that know no boundaries provincial
or international. This phenomenon is known as long-range
transboundary air pollution (LRTAP).
Over time, these emissions expose human beings,
wildlife and resources to diverse quantities and mixtures of air
pollutants. The resulting harm is difficult to evaluate, since it
occurs over varying time frames and over vast areas having differing
degrees of sensitivity. The reversibility of the damage is not yet
well understood.
Some of the chemicals in the atmosphere are
rendered harmless through exposure to sunlight, but others are
extremely persistent, surviving and circulating around the earth for
as long as months or years. They reach our water systems through dry
or wet deposition.
Acid rain, one of the most publicized LRTAP
phenomena, originated with emissions from coal-fired generators,
non-ferrous metal smelters, petroleum refineries, iron and steel
mills, pulp and paper mills, and from motor vehicle exhaust. The
released sulphur dioxide and nitrogen oxides are converted to
sulphuric and nitric acids in the atmosphere. These acids return to
earth through wet sulphate and/or nitrate deposition (including
rain, snow and fog).
In Canada, the major sources of sulphur dioxide
emissions are non-ferrous metal smelters, followed by coal-fired
generators. Motor vehicles and, to a lesser extent, coal-fired
generators, are the major sources of nitrogen oxides. About half the
wet sulphate deposition in eastern Canada is estimated to come from
the United States, while about ten percent of the deposition in the
northeastern United States comes from Canada.
The damage caused by acid rain deposition occurs in
environments that cannot tolerate acidification. Many species of
fish, insects, aquatic plants and bacteria develop reproduction
difficulties. Some even die. The decline in the population of any of
these aquatic organisms affects the food chain. Dwindling
populations of insects and small aquatic plants and animals are
especially serious because the entire food chain is
affected. |
Controlling water pollution
Since water plays such a vital role in life on earth, good quality
water is a precious resource. Often water quality is more important than
water quantity. The quality of a the water affects the use we make of it,
but the reverse is also true. Once we have used the water, we affect its
quality.
This circular process indicates that the traditional habit of
discharging untreated sewage and chemical wastes directly into rivers,
lakes, estuaries or oceans for eventual "assimilation" into the
environment is no longer acceptable, either technically or morally.
The explosion in human population and industrial activities, and the
rate at which new chemicals and products are being developed and
used pose a global environmental threat. The natural decay
processes in water bodies can no longer cope with these loads.
The approach to controlling pollution depends on:
- the type of pollutant
is it degradable? persistent?
is
it a metal? pesticide? dioxin? PCB?
- the source
does it come from an industrial pipe?
a
farmer's field? the atmosphere?
- the effects
is it harming fish? birds? plants? humans?
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Accelerated aquatic plant
growth: too much too fast
The growth and reproduction of aquatic plants is
stimulated by eutrophication, a natural process which, over
geological time, turns a lake into a bog and eventually into land.
But today, in many places, this process is tremendously accelerated
by high concentrations of phosphorus and nitrogen (from fertilizer,
for example) which enrich the water with nutrients, causing the
aquatic plants to bloom. As the plant growth explodes, it chokes off
the oxygen supply normally shared with other organisms living in the
water. When the plants die, their decomposition uses up even more
oxygen. As a result, fish suffocate and die, and bacterial activity
decreases.
Yet if phosphorus and nitrogen inputs are reduced
or stopped, the system can recover by itself. In the late 1960s,
Lake Erie experienced such an extreme case of eutrophication that
fish were dying and the decomposing algae, washed up on bathing
beaches, had to be removed with bulldozers.
The phosphorus (phosphate) in laundry detergents
washed into the lake was the main culprit. A law was passed to
reduce the substance, and in 1972 laundry detergent phosphate
contents were cut by approximately 90%. Lake Erie has since made a
remarkable recovery. |
Water quality objectives and guidelines
In Canada, governments use various measures to protect water quality,
among them guidelines and objectives. The two measures
are similar in that both describe how much of a substance we, as a
society, will tolerate in water. But guidelines and objectives are arrived
at and applied differently.
Water quality guidelines are scientifically determined and indicate the
maximum allowable concentration of substances for a particular water
use such as livestock watering or swimming. These national guidelines
serve as the targets for environmental protection.
Water quality objectives, on the other hand, specify the concentrations
of substances permissable for all intended water uses at a specific
location on a lake, river, or estuary. The objectives are based on
the water quality guidelines for the uses at that location, as well as on
public input and socio-economic considerations.
Water quality guidelines and objectives not only protect water users
and the environment, they also promote sustainable water management
strategies.
Regulations
Ideally, polluting contaminants should be prevented from entering the
water. At the most, in some circumstances, they can be allowed only in low
concentrations. All provinces and territories in Canada have pollution
control regulations. In deciding which substances to control, and to
determine their concentrations and how they may enter the environment, a
number of questions have to be asked, including:
- what are the sources, amounts and effects of various substances?
- what happens to them and what do they do after they have entered the
water? do they change? to what?
- where do the substances end up?
- can they be prevented from reaching the water body or removed by
treatment?
An example of a substance successfully regulated to reduce pollution is
the phosphate found in laundry detergents (see Accelerated
aquatic plant growth). The Canadian Environmental Protection Act
(CEPA) will regulates many more substances that have a deleterious effect
on the environment.
Technology
Technology can be used in many cases to reduce or eliminate substances
that may be harmful to the environment. Sewage treatment plants, properly
operated and maintained, are a means of removing many toxic substances
from wastewater and returning the treated water to a river or lake without
causing harm downstream. Water treatment plants can take river or lake
water and make it fit for drinking.
But what happens when contaminants are not removed, even by the most
modern water treatment methods? They may be present only in minuscule
quantities, but because they are persistent, they can build up to very
harmful levels. In such cases, we can protect future generations and the
ecosystem as a whole in only one way: preventing the chemicals from
entering the water system.
Be a responsible consumer it makes sense
Something all of us, as individuals, can do to protect water quality
and the environment is to recycle products that are not degradable such as
glass, cans and motor oil. Many municipalities in Canada have recycling
programs.
Choose non-hazardous products. Most household chemical products and
pesticides sold in Canada have warning labels. These labels tell whether
the product is flammable, poisonous, corrosive or explosive. Proper
disposal of these products is important to ensure water quality is not
affected.
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What can I do to
improve water quality
In the face of this planet's overwhelming
environmental problems, each individual effort to protect water
quality is vital. Together, individual actions can and do make a
difference to water quality and the environment as a whole. You can
start by taking the following actions:
Avoid hazardous household products
Most proprietary household chemicals are safe to
use and are environmentally friendly, when used according to the
directions on the package. However, some have a harmful cumulative
effect on the environment when they are over-used or incorrectly
disposed of.
- Check the label for hazard warnings. The symbols used on
hazardous household chemical products are shown below:
The warning symbols are based on shape: the more
corners a symbol has, the greater the risk. Read the label to find
out how to use the product safely and what precautions to take.
- Buy only those environmentally hazardous products you really
need, and buy them in quantities you will be able to completely
use up, so that you will not have to worry about disposing of the
leftovers later.
- Use "environmentally friendly" products now available in your
supermarket and drugstore.
- The federal government endorses products that are
environmentally friendly. Look for the Environmental Choice
EcoLogo. Products bearing this label have been tested and
certified by the Canadian Standards Association. Each dove
represents a sector of society consumers, industry, and
government linked together to improve and protect the
environment. The logo identifies the products that maximize energy
efficiency and the use of recycled or recyclable materials and
minimize the use of environmentally hazardous substances.
Consumers can make informed choices.
For more information, contact:
Environmental Choice
Program 
Terra-Choice
Environmental Services Inc.
2781 Lancaster Road, Suite
400
Ottawa, Ontario K1B 1A7
Tel.:
(613) 247-1900
Toll free: 1-800-478-0399
Fax:
(613) 247-2228
E-mail: ecoinfo@terrachoice.ca
Additional information on environmentally
friendly household products and their uses can be obtained from
the following and similar organizations:
Canadian
Manufacturers of Chemical Specialties Association
56 Sparks Street, Suite 500
Ottawa,
Ontario K1P 5A9
Tel.: (613) 232-6616
Fax:
(613) 233-6350
E-mail: morinm@cmcs.org
Consumers
Association of Canada
267 O'Connor
Street, Suite 307
Ottawa, Ontario K2P 1V3
Tel.:
(613) 238-2533
Fax: (613) 563-2254
E-mail: info@consumer.ca
Don't misuse the sewage system
Don't throw waste down the drain just because it's
convenient. Toxic household products can damage the environment and
return to us through water and food.
- toss items such as dental floss, hair, disposable diapers and
plastic tampon holders into the wastebasket, not the toilet
these items create many problems at the sewage treatment plant
- always use up completely (or pass on for other people to use)
the unused contents of oven, toilet bowl and sink drain cleaners;
carpet and furniture cleaners and polishes; bleaches, rust
removers and solvents; paints and glue; and most other acid and
alkali products
- save food scraps (except dairy and meat) and compost them;
don't dump them down the drain
- choose latex (water-based) paint instead of oil-based and use
it up instead of storing or dumping it
Don't use pesticides or other hazardous
materials in your garden
Adopt alternative pest control methods, such
as:
- hand pulling weeds
- snipping and discarding infested leaves
- dislodging insects with insecticidal soap or a water hose
- practising companion planting for more information,
send a self-addressed, stamped envelope to:
Ecological Agriculture Project
Box 191,
Macdonald College
Ste-Anne de Bellevue, Quebec
H9C 1C0
- setting ant and roach traps instead of using chemical sprays
- applying a natural insecticide such as diatomaceous earth,
available in garden centres
- fertilize with natural materials such as bone meal or peat
Don't dump hazardous products into storm
drains
Storm drains empty directly into nearby streams in
many areas. The contents of storm sewers are generally not processed
at sewage treatment facilities and can therefore do immediate harm
to fish and wildlife. Beach closures are a typical example of storm
water pollution in many communities.
- DON'T pour oils, paint compounds, solvents and other
products into storm sewers, onto the street, or into your driveway
- DO take them to local recycling or disposal facilities.
Some communities even organize hazardous waste disposal days;
contact local health and environment officers or waste disposal
companies for details. If nothing comparable exists in your
community, introduce and promote the idea
- DO contact your local Fire Department, which will
normally accept unwanted remainders of barbecue starter fluids,
lighter fluids, gasoline and furnace oils.
Don't forget about water quality even
when you're having fun
- power boats can pollute the water through gasoline leaks and
spills. Consider using a sailboat, rowboat, canoe or kayak. If you
use a powerboat, keep the engine in good repair to avoid leaking
oil, gasoline and solvents
- if you are a cottage owner, make sure you have a proper sewage
disposal system
- while camping, always bury biodegradable waste at least
60 meters (200 feet) from any water source. Use only
biodegradable soaps, and take your non-biodegradable garbage with
you for proper disposal
Take further action
There is more you can do!
- read up on environmental issues
- be willing to change your attitudes, behaviour and
expectations
- write away for more information on environmentally-friendly
products and methods
- urge and support federal, provincial and municipal action on
environmental issues
- join and support local and national environmental groups that
work to solve environmental problems; they are always in need of
more volunteers and different talents
- boycott environmentally harmful products and let the stores
know why
- attend public hearings, participate in advisory boards,
address review committees, request information as a
citizen, you have these rights and should seize these
opportunities
- inform your friends and educate your children
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The choice we make now
Sustainable development
As we enter the 21st century, we find
ourselves at a critical point and with very little time years, not
generations in which to undo environmental damage and bring water
resources to the point at which they can maintain themselves naturally. We
must now think in terms of sustainable development: using and
managing resources and the environment in such a way that they both
maintain a strong economy and preserve a healthy environment today and in
the years to come.
All of us must do our part government, industry, public interest
groups, individuals at home, at school, at the workplace, while
working, while playing, while travelling. It is time to re-examine our
values, make thoughtful choices, and adjust our lifestyles to give more
consideration to the environment. This includes changing our water use
habits in ways that will help the resource sustain itself and maintain its
quality.
It is important for each one of us to act not only for ourselves
and our children, but for future generations and for the other living
things sharing the earth with us.
Freshwater Series A-3
Published by authority of the Minister of the
Environment
©Minister of Supply and Services Canada, 1992
Cat. No.
En 37-81/3-1992E
ISBN
0-662-18069-0 |
