GOALS FOR THE DAY
• Importance of water
• Will we have enough usable water
• Facts about water
• How can we increase water supply
• How Can We Use Water More Sustainably?
• Causes of water pollution
• Effects of water pollution
• Sources of water pollution
• Characteristic of water
• Laws about water pollution
Importance of water
• Water is needed in all aspects of life.
• Water is an essential pre-requisite for
social well-being and economic
productivity.
• Therefore, adequate supplies of GOOD,
QUALITY water should be maintained
for the entire population while
preserving the hydrological, biological
and chemical functions of the
ecosystem.
Importance of water
Will We Have Enough Usable Water?
• We are using available freshwater
unsustainably by wasting it,
polluting it, and charging too little
for this irreplaceable natural
resource.
• One of every six people does not
have sufficient access to clean
water, and this situation will
almost certainly get worse.
FACTS about water
• Around 1.1 billion people globally do
not have access to improved water
supply sources
• 2.4 billion people do not have access
to any type of improved sanitation
facility.
• About 2 million people die every year
due to diarrheal diseases, most of
them are children less than 5 years of
age. (Source: WHO)
• Worldwide, 1 out of every 5 deaths
of children under 5 is due to a water-
related disease.
Water Distribution
on Earth
Source: MITI Environmental Bureau, 1997
Freshwater Shortages
• Causes of water scarcity
• Dry climate
• Drought
• Too many people
• Wasting water
• 2050: 60 countries will face
water stress
• 1 of 7 people – no regular
access to clean water
• Potential international
conflicts over water
How Can We Increase Water Supplies?
• Groundwater used to supply cities and grow food is being
pumped from aquifers in some areas faster than it is
renewed by precipitation.
• Using dams, reservoirs, and transport systems to provide
water to arid regions has increased water supplies in some
areas, but has disrupted ecosystems and displaced people.
• We can convert salty ocean water to freshwater, but the cost
is high, and the resulting salty brine must be disposed of
without harming aquatic or terrestrial ecosystems.
.
WATER SUPPLY
Rainwater Ground water Surface water
Types of Water Supply
• Level 1 – point source
- a protected well or a
developed spring with an
outlet but without
distribution system
Types of Water Supply
• Level 2 - communal faucet
system
- a system composed
of a source, a reservoir, a
piped distribution network
and communal faucets; 1:4
(faucet : HH)
Types of Water Supply
• Level 3 - waterworks system
- a system with a source, a
reservoir, a piped distribution
network and household taps; for
densely populated urban areas
TYPES OF WATER
Mineral Water
• Distinguished from other types of bottled water by
its constant level and relative proportions of mineral
and trace elements at the point of emergence from
the source
Purified Water
• Bottled water produced by distillation, deionization,
reverse osmosis or another suitable process
Distilled Water
• Undergoes the same process as that of purified
water, but is vaporized and condensed after
Increasing Freshwater
Supplies
• Withdrawing groundwater
• Dams and reservoirs
• Transporting surface water
• Desalination
• Water conservation
Fig. 11-9, p. 245
Removing Salt from
Seawater
Major Problems with Desalination
Death of
High cost marine
organisms
Large quantity
of brine
wastes
How Can We Use Water More Sustainably?
• We can use water more
sustainably by cutting water
waste, raising water prices,
slowing population growth,
and protecting aquifers,
forests, and other ecosystems
that store and release water.
Reducing Water Waste
• Increase the cost of water use
• End subsidies for wasteful water use
• Provide subsidies for efficient water use
• Improve irrigation efficiency
• Center pivot
• Low-pressure sprinkler
• Precision sprinklers
• Drip irrigation
• Use less in homes and businesse
Fig. 11-15, p. 251
Fig. 11-18, p. 253
Floods
• Deadly and destructive
• Human activities worsen
floods
• Failing dams and water
diversion
• Climate change will
increase coastal flooding
How Can We Reduce the Threat of Flooding?
• We can lessen the threat of
flooding by protecting more
wetlands and natural
vegetation in watersheds and by
not building in areas subject to
frequent flooding.
Benefits of Floodplains
• 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
Fig. 11-20, p. 256
How Can We Deal with Water Pollution?
• Streams can cleanse themselves of many pollutants if we do
not overload them or reduce their flows.
• Reducing water pollution requires preventing it, working with
nature in treating sewage, cutting resource use and waste,
reducing poverty, and slowing population growth.
WATER POLLUTION
• The introduction into fresh or ocean
waters of chemical, physical, or
biological material that degrades the
quality of the water and affects the
organisms living in it.
• This process ranges from simple
addition of dissolved or suspended
solids to discharge of the most
insidious and persistent toxic
pollutants (such as pesticides, heavy
metals, and nondegradable,
bioaccumulative, chemical
compounds)
Table 11-1, p. 257
SOURCES OF WATER POLLUTION
• Direct (Point source) – occur when
the polluting substance is emitted
directly into the waterway;
• ex. Pipe spewing toxic chemicals
directly into a river
• Indirect (Non-point source) –
occurs when there is runoff of
pollutants into a waterway, for
instance when fertilizer from a field
is carried into a stream by surface
runoff; is often the cumulative
effect of small amounts of
contaminants gathered from a
large area
SPECIFIC SOURCES OF WATER POLLUTION
• Domestic Sewage • Agricultural Run off • Industrial Effluents
EFFECTS OF WATER POLLUTION
• • Unsuitable for drinking,
recreation, agriculture, and
• industry
• • Diminishes the aesthetic
quality of lakes and rivers
• • Contaminated water destroys
aquatic life and reduces
• its reproductive ability
• • Eventually, it is a hazard to
human health
Water–Borne Diseases
• caused by pathogenic
microorganisms that most
commonly are transmitted in
contaminated fresh water
• Causes:
• Lack of proper sanitation (sewage
treatment is inadequate thus, human
wastes disposed in open canals)
• Infection with pathogenic
microorganism
• Chemical poisoning
• Cholera, Typhoid, Amoebic or
bacillary dysentery
Water-Washed diseases -
• caused by poor personal hygiene
and skin or eye contact with
contaminated water; thrive in
conditions where freshwater is
scarce, and sanitation is poor
• Scabies, trachoma and flea, lice
and tick-borne diseases,
conjunctivitis, leptospirosis
Water-Related Diseases
• caused by insect vectors which
breed in water
• Causes:
• Lack of appropriate water
management.
• Construction projects often
increase the mosquito population
due to pools of stagnant water.
• Dengue, filariasis, Malaria,
Onchoceriasis, Trypanosomiasis
Water - Based diseases
• caused by parasites found in
intermediate organisms living in
water
• Causes:
• Stagnant water behind dams and
water channels is ideal for snails.
• Lack of proper sanitation and
clean water supply.
• Schistosomiasis, Dracunculiasis
Ocean Pollution
• Coastal areas – highly
productive ecosystems
• Occupied by 40% of population
• Coastal populations will double
by 2050
• About 80% marine pollution
originates on land
• Ocean dumping controversies
• Algal blooms
• Oxygen-depleted zones
Fig. 11-26, p. 263
Effects of Oil Pollution on Ocean Ecosystems
• Volatile organic
hydrocarbons
• Kill larvae
• Destroy natural insulation
and buoyancy of birds and
mammals
• Heavy oil
• Sinks and kills bottom
organisms
• Coral reefs die
Oil Cleanup Methods
• Current methods
recover no more than
15%
• Prevention is most
effective method
• Control runoff
• Double-hull tankers
Fig. 11-27, p. 264
Characteristics of Water
physical chemical
Biological radiological
PHYSICAL CHARACTERISTICS
OF WATER
• inert suspensions of floating
substances that are carried by water in
its passage through the hydrologic
cycle (rainfall, percolation, runoff,
evaporation)
• Turbidity – a measure of the light-
transmitting properties of water
and is comprised of suspended and
colloidal material
• Color – caused by substances in
solution
• Taste and odor are due to
biological components
CHEMICAL CHARACTERISTICS OF WATER
• Can be organic, inorganic and includes chemicals
that affect water’s aesthetics.
• Affect the behavior and characteristics of the water
in its use for domestic or commercial and industrial
purposes
• pH or alkalinity - due to presence of ions; the capacity
of natural water to neutralize acid added to it (ph = 6.5-
8.5)
• Hardness - due to Calcium and Magnesium; an
indicator to industry of potential precipitation of
calcium carbonates in cooling towers and boilers,
interference with soaps and dyes in cleaning and textile
industries and with emulsifiers in photographic
development.
• Hard water is less corrosive than soft.
• Treatment usually left to consumer (domestic, industrial,
etc) depending on needs.
• Salinity - indicates possible sewage pollution
BIOLOGICAL
CHARACTERISTICS OF WATER
• Refers to the presence of microorganisms,
parasites, microscopic plants and animals
• Bacteria responsible for the breakdown of
complex substances, or are parasitic or
pathogenic or both
• Include microscopic and macroscopic plant
and animal life
• Include plankton, insect and crustacean
larvae and algae responsible for the taste and
odor that water acquires
• Biological Index of Pollution:
• 0-8 = clean water
• 8-20 = slightly polluted
• 20-60 = polluted water
• 60-100 = grossly polluted water
RADIOLOGICAL
CHARACTERISTICS OF
WATER
• Result of nuclear weapons
testing
• Some man-made substances
may also enter drinking water
supplies from processing
facilities, mining areas, and
nuclear power plants
Biochemical Oxygen Demand (BOD)
Chemical oxygen demand
Total solids
PARAMETERS Coliforms
OF WATER Nitrogen and phosphorus compounds
QUALITY
Heavy metals
Oil and grease
pH
Temperature
A. BIOLOGICAL OXYGEN DEMAND (BOD)
• Indicates amount of biodegradable
organic waste in untreated and
treated municipal and industrial
wastewater
• Measures the amount of oxygen
consumed by microorganisms in the
process of decomposing organic
matter
• The harder the microorganisms work,
the more oxygen they use, and the
higher the measure of BOD, leaving
less oxygen for other life in the water.
• Used as a gauge of the effectiveness
of wastewater treatment plants
CHEMICAL OXYGEN DEMAND (COD)
• Used to test wastewater that
contains non-biodegradable
compounds or compounds that
inhibit microbial activities
• High values indicate high levels
of organic pollutants
• Commonly used to indirectly
measure the amount of organic
compounds in water
C. TOTAL SOLIDS
• Refers to matter suspended or
dissolved in water or wastewater
• Includes total suspended solids
(TSS) and total dissolved solids
(TDS)
• TSS – total solids retained by filter
• TDS – total solids that pass
through filter
• High levels can cause health
problems for aquatic life
D. CHOLIFORMS
• Used as an indicator organism
• Indicates fecal contamination
• Causes of contamination: septic
tank failure, poor pasture,
animal keeping practices, break
in the integrity of the
distribution system
NITROGEN AND PHOSPHORUS COMPOUNDS
• Essential for the growth of
microorganisms and plants
• Excessive amounts can lead to
eutrophication –heavy input of
inorganic nutrients to surface
waters that promote the growth
of weeds and algae in slow
moving surface waters
• Arsenic, total mercury, cadmium, organophosphate,
chromium cyanide, lead.
F. HEAVY METALS • Cause damage or death to plant and animal life
• Present with toxins that are harmful to aquatic life
and humans
OIL AND GREASE
• Arise from the use or
manufacture of fats and oils
or from activities that
involve these substances
pH
• Measure of the
concentration of
hydronium ions
(H+) in water
• Pure water: ph7
• Should be
between 6.5-8.5
TEMPEATURE
• Affects biological activity, the
action of toxins and oxygen
concentration
• Solubility of oxygen decreases
with increasing temperature
• Rate of biological activity
doubles for every 10 to 15oC rise
or decrease within the range of
5 to 35oC
PREVENTION
• Water Quality Control
• Inspection and survey of water
supply sources
• Water sample collection and
bacteriological examination
• Chlorination of water supply
sources
• Improvement/upgrading of
provincial water laboratories
• Proper Excreta Disposal
Purifying Drinking Water
• Developed countries
• Reservoir storage
• Purification plant
• Developing countries without
purification plants
• Clear plastic bottle in sun,
with black side
• LifeStraw
WHAT CAN BE DONE?
Water Purification – production of hygienically safe and
aesthetically pleasing water from a polluted
orcontaminated source
• Purification by nature:
• 1. Evaporation and Condensation
• 2. Aeration – exchange of gases between atmosphere and
water
• 3. Gravity
• 4. Biologic forces
Water can be Purified by:
• Distillation -- The water is vaporized (heated into steam)
then condensed (cooled back to liquid form). This
process removes dissolved materials originally present
in the water.
• Reverse Osmosis -- The water is forced through
membranes that remove 90 percent of the dissolved
minerals.
Sewage Treatment Systems • Rural and suburban
areas – septic tanks
• Urban areas –
wastewater treatment
plants
• Primary sewage
treatment –
physical process
• Secondary sewage
treatment –
biological process
• Chlorination –
bleaching and
disinfection
Improving Sewage Treatment
Systems that exclude hazardous and toxic chemicals
Require businesses to remove harmful chemicals before sewage sent to treatment plant
Reduce or eliminate use of toxic chemicals
Composting toilet systems
Wetland-based sewage treatment
PURIFICATION BY MAN (HOUSEHOLD METHODS
OF
WATER TREATMENT)
• Sedimentation- allowing impurities to settle at the
bottom
• Aeration - transferring the water from one
container to another
• Flocculation & Sedimentation - use of aluminum
sulfate crystals
• Filtration - use of cloth and sand
• Chemical Disinfection – chlorination
• Coagulation – process of collecting the finely
suspended material to form aggregates then
removed by a filter; use of aluminum crystals
• Boiling
• Kills all vegetative organisms
• Kills all pathogens, including viruses
• No special equipment required
• Requires fuel (electricity assumed not available)
• Time consuming
Real cost of bottled water
• https://www.youtube.com/watch?v=m1uDvzytyEA
Preventing Nonpoint Source Pollution
Use plant buffer
Mostly agricultural Use vegetation to Reduce fertilizer zones around
waste reduce soil erosion use fields and animal
feedlots
Keep feedlots
away from slopes, Integrated pest Organic farming
surface water, and management methods
flood zones
Fig. 11-29, p. 269
Fig. 11-30, p. 269
o Standards for drinking water; bacteriological and chemical
PROTECTIVE examinations; evaluation of results – conform to the National
Drinking Water Standards
MEASURES-
Presidential o Treatment of water; disinfection of contaminated water sources;
distribution systems – conform with procedures of DOH
Decree No.
856 – Code of o Sites of water sources; delivery of water to consumers; operation,
plans and specifications of water system; and certification of
Sanitation potability of drinking water - should be approved by the Secretary of
Health.
ofthe o Initial and Periodic examination are required for drinking water. o
Philippines Examination should be performed only in private and government
laboratories accredited by DOH
To Protect drinking water form contamination, the following
measures shall be observed:
A. Washing clothes or bathing within a radius of 25 meters from any well or other source of
drinking water is prohibited.
B. No artesian, deep or shallow well shall be constructed within 25 meters from any source of
pollution.
C. No radioactive sources or materials shall be stored within a radius of 25 meters from any
well or source is adequately and safely enclosed by proper shielding
D. No person charged with the management of a public water supply system shall permit any physical
connection between its distribution system and that any other water supply, unless the latter is regularly
examined as to its quality by those in charge is made and found to be safe and potable .
E. The installation of booster pump to boost water direct from the water distribution line of a
water supply system where low-water pressure prevails is prohibited.
Activity for the week
• Watch this clip:
• https://www.youtube.com/watch?v=YSkNprbnDz0
Guide questions:
• 1.What are the effects of water pollution on the environment and the people of Rosario?
• 2.What measures have been taken to address the issue of water pollution in Rosario?
• 3.Have the measures taken been effective in reducing water pollution, and if so, how?
• 4.Are there any ongoing efforts to prevent water pollution in Rosario, and if so, what are
they?
• 5.What can individuals and communities do to help reduce water pollution
