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COMMUNITY WATER and WATER SANITATION
Three Broad Headings of Community and Population Health Strategies:
1
...
Health Protection
3
...

Water supply Sanitation is one of the top priority activities in the field of
environmental sanitation
...

Providing safe water in rural areas, the incidence of cholera can be
reduced to almost 70%
...

Hydrologic Cycle – refers to the recycling and purification of water through the
air and soil
...

Two main determinants of Public Concerns:
1
...
environment
We do not manage environment, we manage our interaction with the
environment
...

Growing population and the run off conditions of some regions place an
increasing burden on communities
...

 Acute effects - from infection and poisoning or teratogenesis
 Chronic effects – developmental abnormalities, mutagenesis,
oncogenesis, neurological and behavioural impairment
...

Distribution and trends
Infectious and toxic agents affect people differently, depending on
their sex, age, history of pat exposure
...

Control measures
Current evidence build a convincing case for the carcinogenicity in
humans of twenty chemicals and compounds; over 2,300 specific chemicals
are suspected carcinogens
...

Health and Education
Access to information and education about hazardous exposures is an
essential goal
Water Uses
Population need water for recreation, irrigation, industry, aesthetics and
domestic use
...
Microbic diseases are those caused by specific organism
...
Bacterial
b
...
Protozoan
d
...
Non microbic are those that arise from the presence, or an excess, of
certain chemical substances in the water
...

Heavy Metal Poisoning
a
...
Mercury poisoning from drinking water
contaminated with mercury waste
...

Nitrate Poisoning caused by the presence of excessive nitrates
in water
III
...
Water – washed diseases are diseases transmitted from person to
person as a result of an inadequate supply of water for personal
hygiene and / or domestic cleaning
...


Substances found naturally occurring in water as industrial pollutants can be
harmful when they reach concentrations above levels established by
regulatory bodies
...

Maximum levels permitted are usually stated in milligrams per liter of water
(mg/)
Pesticides – present in water primarily as a result of vector control, crop
spraying, and agricultural runoff and spills
...
Water based diseases are those caused by agents spread by contact
with or ingestion of water
...
: Schistosomiasis
5
...
Examples of these are Dengue, Filariasis and
Malaria
...

Produced by chemical reactions
Trihalomethanes
in water that has been
Liver, kidney
disinfected by chlorine
damage, cancer
Old piping and solder in public
Nerve problems,
Lead
water distribution systems,
learning disabilities
homes and other buildings
in children, birth
defects, possibly
cancer
Waste from many outmoded
PCB’s
manufacturing operations
Liver damage, cancer
Pathogenic
Leaking septic tanks, overflowing AGI, meningitis
bacteria and
lines
viruses
Endrin and Lindane – pesticides commonly used on field crops
- Most toxic and must be limited in their concentration in water
supply
Herbicides – used in weed control
- Muscular tenses, paralysis, coma
- May trigger mutations and teratogenic effects
Radionucleotides
 Uranium
 Radon
carcinogenic
 Radium
Occur naturally in groundwater and to lesser degree in surface water,
as leaching from rock deposits
...
01 mg/L standard
CHARACTERISTICS OF WATER
Water possesses certain characteristics which directly or indirectly affects its
quality
...

1
...
Turbidity is
caused by impurities in suspension while color is imparted by the
substances present in solution
...

Turbidity – refers to the cloudiness of water caused by variety of
suspended materials, sometimes organic but usually inorganic
- Makes disinfection and bacteriological analysis difficult
...

2
...

Corrositivity– the tendency of water to corrode metals
...

Page 3

3
...

Presence of these impurities also serves as an index of the
pollution degree of the water source
4
...
Manmade radionuclides arising from power generated by
nuclear energy are also radioactive contaminants
...

Other sources of contaminants are:
1
...

2
...
Medical use of radioactive substances

COMMON WATER QUALITY PROBLEMS ASSOCIATED WITH CERTAIN
CHARACTERISTICS AND THEIR POTENTIAL SOURCES/CAUSES
CHARACTERISTIC
a
...
Chemical
- Hardness

-

chloride

-

iron

SOURCES
Suspended particle
Substances in
solution, eg
...
Hydrogen
sulfide

Cloudy water

Dissolved Calcium
and Magnesium

Increased soap
consumption ;
formation of scales
in boiled water
Salty taste of water

Dissolved salts
sewage
Dissolved iron

Waterborne infectious disease
Pathogens of humans do not normally multiply in water, yet they can survive
in water and remain virulent enough to set up an infection in a new host
...
Biological
- Bacteria, viruses,
parasites
- Microscopic plants

Typhoid
Paratyphoid
Giardiasis
Cholera
Bacillary dysentery

COMMUNITY and POPULATION HEALTH

PROBLEM

sewage
Organic content of
water

Colored water

Disagreeable odor

Staining fixtures
yellow colored
water, metallic taste
of water
Water and food
related disease
Color, odor, taste

five infectious disease
transmittedb y water

Page 4

WATER SUPPLY SOURCES

-

For community and population health purposes, water must be sufficient in
supply and free from contamination and pollution
...


-

The challenge for a community and population health, usually managed by
public health agencies is to ensure the minimal; concentration of
contaminants and to monitor outbreaks with specific intervention on the
sources of any outbreaks
...

A
...
appears small holes or wet
spots
...
Underground Source – safe
- low capital funds and operating cost
- first requirement is to find an adequate supply
by locating gravel bed that sereves as a
natural reservoir
- test wells are drilled to outline the reservoir
...

2
...


C
...
Groundwater supply
- from shallow wells and deep well, and spring
- part of the atmospheric water or rain that percolates through the
ground and recharges the aquifers or water bearing formations
...
It combines with
solids to form a flaky hydrate or floc
...

-

Water is retained in the tank for 2 hours to allow floc to settle to the
bottom of the tank where it will be scraped into troughs
...
25
and 0
...
FLASH MIX
2
...
SEDIMENTATION
4
...
CHLORINATION

COMMUNITY and POPULATION HEALTH

Page 6

TESTING OF WATER
Coliform Test – standard test of drinking water
- coliform organisms are not pathogenic but because they are always
present in the intestinal tract, their presenc e of water is a sure
indicator of fecal contamination
Chlorine Test
- chlorine residual determination is a simple test to ensure that a
sufficient level of chlorine is being maintained
...

- designed to deliver 40-80 liters of water per capita/ day for 100
households
- suitable for rural and urban areas where houses are clustered densely
LEVEL 3- WATERWORKS SYSTEM
- with source, transmission pipes, reservoir, piped distribution network
for household taps

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