Demography

&
Population Studies

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 Demography & Population Studies

▪ Demography >> derived from the Greek word demos >>

people and grapho>> writing- science of population
study especially human beings.
▪ i.e the quantitative study of the size, structure,
characteristics and territorial distribution of human
populations and the changes occurring in them over a
period of time.
▪ Demographic analysis may cover whole society or groups
defined by criteria such as education, religion, income,
religion etc.
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 Demography & Population Studies

▪ Size refers >> actual number of population,

▪ Structure refers >> age and sex structure of the
population
▪ Characteristics refers >> marital status, literacy,
language, ethnicity, religion, income etc.,
▪ Territorial distribution >> distribution pattern of the
population within a defined territory.

Demography & Population Studies 3

 Population Studies

▪ In the broader sense Demography >> population studies

+ quantitative study of the population, the study of
interrelationships between population and socio-
economic, cultural and other variables.
▪ Therefore, for planning or research >> the causative
variables (social, economic, political etc…..) for
population change >> need to be considered

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 Population Studies

▪ Determinants (key factors) of Population Change

(Demography)
➢ Population change is the change in number of people in
a specified area during a specific time period.
➢ Forms of change in territorial boundaries, ie. The changes
in size, growth & structure and distribution of a
population are determined mainly by three types/aspects
of events:
▪ Birth (fertility)
▪ Death (mortality)
▪ Migration (in-migration and out-migration) >>(
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immigration and emigration
 Determinants of Demography or causes of
Population Change (Population Dynamics)
▪ During a given span of time births will increase the
population whereas deaths will decrease the
population.
▪ Similarly, in-migration will add to the existing population
while out-migration will lead to a decrease in the
population.
▪ All three determinants of population change are affected
by various socio-economic and cultural factors.

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 Determinants for Population Change

Births/ Fertility and its measures

▪ can be affected by periods of peace or war, prosperity

or depression, marriage rates, attitude towards family
size, etc. such as past insurgency in Nepal, Muslim vs
others, etc.

▪ some of the common demographics measures used in

relation to fertility are crude birth rate, general fertility
rate, age-specific fertility, total fertility rate etc.

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Births/ Fertility and its measures
1. Crude birth rate (CBR)
Annual births divided by total mid-year population or the
no. of birth per 1000 population.
=Annual Births
Total mid-year population
Or
No. of births per 1000 population
i.e = (B/P)X 1000

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Births/ Fertility and its measures
2. General Fertility Rate (GFR)
When data are available according to age & sex-distribution
of population, some improvement over CBR can be
obtained by suing GFR. It is the no. of birth per 1000
women aged 15-49
i.e. GFR= total annual births X 1000
total mid-year population of
women aged 15-49

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Births/ Fertility and its measures
3. Age specific fertility rate (ASFR)
Live birth to women aged X in a year divided by mean
population of women aged x
i.e. ASFR= live birth to women aged X in a year
mean population of women aged X of same year

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Births/ Fertility and its measures
4. Total fertility rate (TFR)
By adding ASFR for women from 15-49 years of age one
can obtain TFR. It is the index of childbearing performance
of a woman or group of women during her//their total
childbearing period

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 Determinants for Population Change

▪ Deaths/ mortality & its measures

▪ can be similarly influenced by various factors such as
peace or war, prosperity or depression, crimes,
accidents, outbreak of epidemic, etc. such as Hirosima
& Nagasaki, Japan, Sunami/earthquake in Indonesia,
Covid 2021 etc.
▪ It’s the number of deaths in a given time or place of the
proportion of deaths in relation to a population.
▪ Demographic measures if mortality includes crude
death rate, infant mortality rate, life expectancy, etc

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Deaths/ mortality & its measures
1. CDR (Crude Death Rate)
It is the total no. of deaths of person of all ages in 1 year
divided by total population at the mid of that year.
2. ASDR (Age specific Death Rate)
Total no. of deaths to persons un X specific age group
(except for infants< 1 year) by total population in that age
group at the mid of the year. Usually 5 year age group are
taken.
ASDR= death at aged X in a year
mid year population aged X
Deaths/ mortality & its measures
3. Average life expectancy at birth
Avg. no. of year a newborn can expect to live if they are
exposed to experience the current ASDR. One can also
compute life expectancy from other ages. E.g. 20 years or
65 years, etc.
4. Infant mortality rate
It is the no. of deaths to children under 1 year of age per
1000 live births in the same year.
5. Child mortality rate
No. of deaths to children aged between age 1 yr & 5 year
per 1000 children in the same age group (mid year)
 Determinants of Population Change

▪ Migration >>
▪ Geographic or spatial mobility for permanent change in
usual residence between clearly defined political statistical
units
▪ better economic opportunities (mostly), attraction of
milder or more suitable climates, desire for better living
or housing conditions (applies particularly to short
distance migration within the same general locality), and
movements for reasons of health, education or
retirement.
▪ also influenced by peace or war, prosperity or depression
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etc. eg. US, Australia, Canada, Syria, etc.
 Determinants of Population Change
Migration >>
▪ In-migrant- person who moves in a political area within the
same country
▪ Out-migrant- person who moves out of a political area
within the same country
▪ Immigrant- International migrant who enters the area from
a place outside the country
▪ Emigrant- International migrant departing to another
country by crossing international boundary.
▪ Net migration: In-migrant-Out migrants
▪ Net immigration: Immigrants-Emigrants
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▪ Gross migration: in-migrants + out-migrants
Sources of Demographic Data
The sources of demographic data are mainly:
▪ Population census
▪ Registration of vital events, and
▪ Sample survey
 Sources of Demographic Data

A. Population Census >> it is the total process of

collecting, compiling, evaluating, analyzing and
publishing demographic, physical (buildings/
infrastructures), social, economic data within a specified
time to all persons of a country or a well-defined part of a
country.
▪ Taken every 10 years.
Census started >> very early times from the Sumerian
civilization mainly for taxation and recruitment
(compulsory enrollment for national service) purposes.
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 Sources of Demographic Data
▪ Women and children were generally unaccounted for
Modern census evolved during the 17th and 18th centuries.

▪ The process involved complete details of the entire

population and the collection of information about
important characteristics of each person at regular
intervals.

The first census was commenced in 1665 in New France

(Quebec) and Acadie (Nova Scotia).
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 Sources of Demographic Data
The first census was carried out in the U.S.A. in 1790 and in
England in 1801.
After World War II, UN assist >> Administrative and Welfare
Planning in developing countries >> setting up Census
operations

Today census of population is considered as a vital

state’s function all over the world.

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 Sources of Demographic Data
In census operation >> each individual >> important
characteristics such as sex, age, marital status, religion,
literacy, educational attainment, income, occupation,
language etc. is recorded.

Regular intervals, e.g. every 5 or 10 years. >> conducted by

the government.
In Nepal >>every 10 years >> Central Bureau of Statistics
(CBS) is conducted under the National Planning
Commission.
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 Sources of Demographic Data
Using Census Information in Planning

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 Sources of Demographic Data
Population Census
▪ National Population and Housing Census (NPHC) is
part of integrated national statistical system of Nepal
▪ It provides the benchmark for population count at national
and sub-national levels at regular intervals of ten years.
▪ In Nepal, the Central Bureau of Statistics (CBS), under
the National Planning Commission (NPC), Government
of Nepal (GoN), is responsible for planning,
implementation and management of all census activities,
including collection, processing, editing, tabulation of data
and final dissemination of results.
▪ First population census of Nepal dates back to 1911. 23
 Sources of Demographic Data
B) Vital Registration System(VRS) / Civil Registration
System
▪ It is the legal registration, statistical recording & reporting
of the various events which include collection, compiling,
analysis, presentation & distribution of statics pertaining to
vital events which in turn include:
1) birth 2) death 3)marriage 4) divorce.
A birth, death or marriage certificate >> issued as a proof
>> which assists in legal matters >> like citizenship,
properties, inheritance etc.

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 Sources of Demographic Data

Normally, during Registration, additional information is

recorded along with the record of vital events >> such as
information on date of birth, sex, age of mother, number of
previous children, order of birth, residence of mother etc.
In case of Death >> date, age and sex of the deceased,
place of occurrence, residence, cause of death, etc. is
recorded.
In developed countries the vital registration system is very
effective, and the records are up to date and reliable.
On the other hand, in the developing countries many events
are not registered so the records generally tend to be
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incomplete and unreliable.
 Sources of Demographic Data

In Nepal registration of vital events was initially conducted by

the Office of the Registrar under the Ministry of Home.
Currently, this is being done by the local authorities>> i.e
Mahanagarpalika, Upamahanagar Nagarpalika,
Nagarpalika & Gaun palika.

C. Sample Survey >>

Information is collected only from a sample of the
population which is representative of the whole and from
which conclusions can be drawn about the whole, using
scientific methods.
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 Sources of Demographic Data

It is useful in collecting information when proper registration

systems are absent and when there is a long period before
the next census is held.

Specially trained interviewers conduct the survey using

specially prepared questionnaires to obtain the
necessary information. As a result the quality of
information can sometimes be better than the other
sources.
Advantage >> can be done anytime, in less time and for a
lesser cost.
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 Population Composition (Structure) and
Distribution, Population Projection and their
Importance in Planning

▪ Population Composition is the description of the

characteristics of a group of people in terms of factors such as
age, sex, marital status education, occupation, etc.
▪ Of these, age and sex composition is widely used.
▪ For any planning analysis, it is important to study the population
size, its current composition and distribution and its effect on
social, economic and cultural environment of the nation or
region.
▪ It helps in useful management and implementation of all kinds
of public works and land development activities.
▪ Very useful >> in execution & revision of plans 28
 Population Composition and Distribution,
Population Projection and their Importance in
Planning
Population Structure
a) Sex Structure
▪ Sex Ratio >> no. of Males per 100 females or vice-versa
▪ For eg, sex-age ratio >> school age population >> future
estimates for educational institutions, playgrounds,
teachers, text books etc. can be made
▪ Open space requirements as well as the community
facilities required by the different age groups, viz. children,
teenagers, families, and old age groups will also be
determined by the population structure.
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 Population Structure
b) Age Structure
▪ Age data are usually available in single years, however, it
is customary to classify the population in five year age
groups, e.g. 0-4, 5-9, 10-14 etc (Age Cohert).
▪ Age Structure >> Age Pyramid >> also referred to as the
Age-Sex histogram>> Population Pyramid
▪ The age-sex pyramid of developing countries normally
has a broad base and tapers towards the top while that
of developed countries is comparatively more uniform.

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 Population Structure
b) Age Structure

▪ As in the case of sex structure, the age structure of the

population is also affected by fertility, mortality and
migration.
▪ In addition, war plays an important role in the age
structure as mortality is high among younger people
and fertility tends to fall.
▪ However, fertility tends to increase soon after a war as
evidenced by the baby boom in the post war period.

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 POPULATION STRUCTURE

The population pyramid displays the age and sex structure of a country or
given area

Old
Dependants

Economically
Population in Active
Five Year
Age bands
Young
Dependants

Usually, but not always, FEMALES

MALES In % to make for easier To the right
To the left comparisons
between countries
Population pyramid of Nepal

Demography & Population Studies 33

 -1.1
1.4
-1
1.1
-1.4
1.6
Population Studies -1.9
2
-2.6
2.3

-3.3 3.1

-4.2 3.9

-5.3 4.9

-6.6 6.5

-8 7.8

-9.1 9.6

-11 11.3

-11.6 11.3

-12 12

-11.6 11.5

-9.4 9.6

-15 -10 -5 0 5 10 15

Uban Female Urban Male

Back
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 Population Characteristics

▪ Population Characteristics
▪ Shows relationship between different Attributes of the
population >> marital status, literacy, income,
language, religion, occupation, household size etc.
▪ strong co-relation on population structure (Sex & Age).
▪ For eg, higher rate of marital status will result high
fertility whereas higher literacy and income results low
fertility and low mortality. Similarly, fertility can also be
influenced by religion.

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 Population Distribution
▪ Spatial distribution >> is described in terms of spatial
density, composition and dynamics and seeks to provide
explanations for the changes in the pattern of population
distribution.
▪ Influenced by different factors
▪ a) geographical factors (Climate, landforms in terms of
altitudes, quality of soil, water, availability of energy and
mineral resources etc.
▪ b) economic and social factors and
▪ c) demographic factors.
Directly affects planning >> in terms of allocation of various
land uses and where to provide infrastructure and social36
and economic facilities.
 Population Projection
▪ Essential for planning future needs of the public &
private sector at state or country level
▪ It depends on a time frame set by the plan and on the type
of the projects
For eg. water supply scheme for an urban area, 50 to 60 or perhaps
even 100 years into the future.
▪ There are various analytical, graphical and mathematical
methods of making population forecasts.
▪ The common forms of the analytical approach are the
cohort-survival method, the migration, etc.

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 Population Projection
▪ Age groups and Sex groups >> year by year / five-year
interval basis Normally its done for five years.
▪ The fertility ratio is used to fill in estimate of new persons
in the 0-4 year category.
▪ Fertility ratio is the number of children per 1000
females of child bearing age at the end of the five year
time span.

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 Population Projection
▪ Migration rates and natural increase rates are
estimated from past trends.
▪ Graphical methods plot past trends on plain coordinate
graph paper and uses the best-fit straight line projection to
estimate the future population.
▪ Mathematical models use simple linear regression (least
squares) model, multiple regression model, non-linear
models such as the Gompertz or Logistic models, etc. etc.

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 Population Projection

▪ Calculation methods:
▪ Arithmetic methods or projection>> linear change & geometric
growth method.
▪ Exponential growth model

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 Population Projection of Nepal

https://www.macrotrends.net/countries/NPL/nepal/populatio
n-growth-rate
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 Population Projection of Nepal

https://www.macrotrends.net/countries/NPL/nepal/populatio
n-growth-rate

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 Population Projection of Nepal

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https://www.macrotrends.net/countries/NPL/ne
pal/population-growth-rate
 What Population Pyramids Show Us

Economically Economically
More Less
Developed Developed
Country Country
KEY
slope of pyramid indicate the death rate

width of the base is related to birth rate/fertility rate

proportions of men and women can suggest male or female migrations

height of graph can indicate life expectancy (ignore the very thin end of the
wedge as occurs on graph B as these people are a definite minority)

"kinks" indicate dramatic reductions in birth rate or increases in

death rate in the past

area of graph indicates total population - compare areas of different

population age groups or different sex on one graph

The overall shape of the population pyramid can indicate whether it is an

Economically More Developed Country or Economically Less Developed Country
 Population Pyramids related to the
Demographic Transition Model

Stage 1 Stage 2 Stage 3 Stage 4

IMPLICATIONS IMPLICATIONS IMPLICATIONS IMPLICATIONS

Both birth rates and Population starts Population continues Low Crude Birth Rate
Death rates are to grow at an to grow but at slower and Crude Death Rate
High, so population exponential rate due to rate. Low C Death Rate. Higher dependancy ratio
growth rates are fall in Crude Death Rate. Dramatically declining and longer life expectancy
slow but population More living In middle age. Crude Birth Rate. Crude Death Rate does
Is usually restored Life expectancy rises Rise slightly because of
Due to high birth Infant mortality rate falls. EXAMPLES The ageing population
Rate. Short life
Scotland 1870 -1950
Expectancy EXAMPLES EXAMPLES
Algeria, Tunisia
Scotland 1760 - 1830 Morocco Scotland today.
EXAMPLES Republic of Congo Japan, USA
Scotland before 1760
New Guinea
Remote parts of
Amazonia
Demography & Population Studies
Employment

▪ Introduction
▪ Types
▪ Economical importance
▪ Social importance
▪ Employment and planning
 Employment

▪ According to ILO, gainful employment is one of the basic

needs of society
▪ Economic health of a society is in many ways determined
by level and type of employment of its population
▪ More employed is the population>> more robust and
healthier is the economy.
▪ Less employed is the population>> more depressed is the
economy
 Employment

In planning, the study of employment patterns of a city or

region is often carried out to assess the strengths and
weaknesses of the economy and propose necessary actions
to improve it.
The “location quotient analysis” and “shift-share analysis”
compare employment data of the city or region with the
employment data of the nation to determine which
industries are export based and whether they are fast
growth or slow growth industries and how competitive they
are in relation to other similar industries of the country.
 Employment

Location quotient analysis

A location quotient (LQ) is an analytical statistic that
measures a region's industrial specialization relative to a
larger geographic unit (usually the nation)
Shift-share analysis:-
Shift Share Analysis is another tool for economic
development use to analyze changes in their regional
economy. Basically, it looks at several of the factors that
contribute to the growth or decline in a region
 Employment Types

Examples of formal sector firms:

Private/ Community colleges/ schools; Companies; Pvt. Ltd.; Any industries;
Supplier company; Offices/ consultancies; Contractors,.. etc
Employment Types

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 Employment- Economic Importance

▪ Employment provides income to poor families, revives domestic

demand for goods and services, and stimulates overall growth.
▪ William Baumol, author of “Macroeconomics,” explains that the
employment rate and economic growth are linked.
▪ This is because employment contributes to economic growth: Workers
produce valuable goods and services, and in turn receive a wage which
they can spend on buying the goods produced.
▪ High employment means a greater number of goods can be produced as
well.
▪ Before the industrial revolution, workers relied only on what they could
produce individually.
▪ This resulted in a limited number of products for sale, which generally
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included meat, grains and textiles.
 Employment- Economic Importance

▪ As production and employment with a business grows, so too does the

variety of goods and services offered.
▪ The availability of electronics, various specialty foods, clothing and other
retail items is due entirely to the expansion of employment opportunities
and an able workforce willing to produce these items

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 Employment- Social Importance

▪ Socially, employment can also promote social healing, encourage the

return of displaced persons, and improve social welfare in the long run.
▪ The social costs of insufficient or low quality employment involve
diminished standards of living, devalued employee contribution to
production, weakened social ties with the potential for increased social
conflict, and the economic costs of unused or underused human capacity
▪ Getting more of the population into the labor market (and into
employment) is not only good for GDP, but also contributes to how
satisfied people are with their lives.
▪ Job loss might bring a certain stigma as well as feelings of shame and
worthlessness

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 Employment- Social Importance

▪ In addition to providing personal income, employment addresses broader

societal needs: it helps grow, through the collection of taxes, resources
for various community programs
▪ Unemployment causes workers to suffer financial hardship that impacts
families, relationships, and communities. When it happens, consumer
spending, which is one of an economy's key drivers of growth, goes
down, leading to a recession or even a depression when left
unaddressed
▪ The political leadership of every country has to deal with an
unemployment problem since unemployment leads to poverty, low
quality of life, social, political and economic ill

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 Employment & Development Planning

▪ Study of employment scenario is very important in planning

▪ It helps to identify the strengths and weakness of a particular
economy and helps in development prioritization for overall
development
▪ Inclusive growth is defined as a high-employment economy
delivering economic, social and territorial cohesion.
▪ Without a broad participation in the labour market, a sustainable and
inclusive growth is not possible.
▪ Secure jobs with social benefits and fair pay offer a way out of
poverty, which explains why employment is a key pillar of
development. ... The income generated as a result boosts demand
among local traders – thereby creating a cycle that promotes the
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economy and employment
 Transportation
Introduction
▪ It is the movement of humans, animals, and goods
from one location to another.
▪ Transport enables trade between people, which is
essential for the development of civilizations
Mode of Transportation
▪ Include air, land (rail and road), water, cable,
pipeline, and space.
▪ The field can be divided into infrastructure, vehicles,
and operations. ▪ Air
Modes:
▪ Land: Road, Rail
▪ Human- powered
▪ Water
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▪ Animal Powered
▪ Other modes
 Transportation- Economic Impact
▪ Transport is a key necessity for specialization—allowing production
and consumption of products to occur at different locations.
▪ Throughout history, transport has been a spur to expansion; better
transport allows more trade and a greater spread of people.
▪ Economic growth has always been dependent on increasing the
capacity and rationality of transport
▪ But the infrastructure and operation of transport have a great impact
on the land, and transport is the largest drainer of energy, making
transport sustainability a major issue
▪ Due to the way modern cities and communities are planned and
operated, a physical distinction between home and work is usually
created, forcing people to transport themselves to places of work,
study, or leisure, as well as to temporarily relocate for other59 daily
activities.
 Transportation- Economic Impact
▪ Passenger transport is also the essence of tourism, a major part of
recreational transport.
▪ Commerce requires the transport of people to conduct business,
either to allow face-to-face communication for important decisions or
to move specialists from their regular place of work to sites where they
are needed

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 Transportation- Environmental Impact

▪ Transport is a major use of energy and burns most of the world's

petroleum. This creates air pollution, including nitrous oxides and
particulates, and is a significant contributor to global warming
through emission of carbon dioxide, for which transport is the fastest-
growing emission sector
▪ Other environmental impacts of transport systems include traffic
congestion and automobile oriented urban sprawl, which can
consume natural habitat and agricultural lands.
▪ By reducing transport emissions globally, it is predicted that there will
be significant positive effects on Earth's air quality, acid rain, smog, and
climate change.

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 Transportation- Environmental Impact

▪ Prioritization of public transport, bicycles, and pedestrian movement

is becoming popular approach to cut down CO2 emission
▪ Redirecting vehicle movement to create 20-minute neighborhoods
that promotes exercise while greatly reducing vehicle dependency and
pollution.
▪ Some policies are imposing a congestion charge to cars for travelling
within congested areas during peak time

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 Transportation- Sustainable Development Impact

▪ The United Nation had first formally recognized the role of transport
in sustainable development in the 1992 United Nation's Earth summit.
▪ In the 2012 United Nation's World Conference, recognized that
transport and mobility are central to achieving the sustainability
targets.
▪ In recent years, data has been collected to show that the transport
sector contributes to a quarter of the global greenhouse gas emissions,
and therefore sustainable transport has been mainstreamed across
several of the 2030 Sustainable Development Goals, especially those
related to food, security, health, energy, economic growth,
infrastructure, and cities and human settlements.

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 Transportation- Sustainable Development Impact

▪ There are various Sustainable Development Goals (SDGs) that are

promoting sustainable transport in order to meet the defined goals.
▪ These include SDG 3 on health (increased road safety), SDG 7 on
energy, SDG 8 on decent work and economic growth, SDG 9 on
resilient infrastructure, SDG 11 on sustainable cities (access to
transport and expanded public transport), SDG 12 on sustainable
consumption and production, and SDG 14 on oceans, seas, and
marine resources.

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Transportation- Classification of Urban Road

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Transportation- Classification of Rural Road

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 Transportation- Street Design

▪ Traffic volume(nos. of vehicles per hour) determines the road width

& type
▪ Street Design includes various components like; right of way ,
parking, sewer line , electricity, w/s line, drainage, telephone, etc.
▪ Also provides space for pedestrians, malls, sculptures, monuments,
etc.
▪ Usually, minor streets consists of traffic lane of 9-10 feet wide & for
highways minimum width of single lane is taken as 12 feet
▪ Vertical clearance and sidewalks are designed as per hierarchy of
roads
▪ Intersections are very important in design for safety and comfort
▪ Design of street can be influenced from its historical value 67
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 Transportation
Ministry of Physical Infrastructure and Transport (MoPIT)
▪ The main aim of organization is to harmonize the policies and bring
efficiencies and effectiveness in the provision of infrastructural
services.
▪ Charged with the responsibilities for enhance the economic and
social development of country by linking various geographical and
economic regions through the national strategic transport network.
▪ Responsible for linking rural areas of country with markets to
support various economic activities and projects related with
tourism, agricultural, electrical, industrial and other sectors of Nepal
 Transportation
Ministry of Physical Infrastructure and Transport (MoPIT)
▪ Key role of the Ministry lies with preparing plans, policies and
programs regarding development of physical infrastructures such as
roadways, railways, waterways, subways, flyovers and ropeways;
Transport (except Air Transport) and transit management and its
operation related plans, policies and programs; its implementation;
monitoring and evaluation; inspection.
▪ DoR, CAAN, Department of Railway

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 Utilities and Services: water supply
▪ Water supply >> water quality, continuity of supply, service quality (
water pressure, Ministry of water supply
▪ Source: For small area>> deep ells, lakes, streams
For large area>> surface water like river, lakes >> eg,
Melamchi, Sundarijal in Kathmandu, Godavari in Lalitpur
▪ Use: for household uses and fire fighting
▪ Demand calculation: liters per capita per day (LPCD)
▪ Developed country: more than 500 lpd ( calculated in 700 lpd)
▪ Developing country: less than 50 lpd
▪ Current demand: more than 300 lpd
▪ Current supply: 120 lpd ++
▪ Distribution system: Grid iron system; Dead end system
 Utilities and Services: water supply
▪ Water supply >> water quality, continuity of supply, service quality (
water pressure, Ministry of water supply
▪ Source: For small area>> deep ells, lakes, streams
For large area>> surface water like river, lakes >> eg,
Melamchi, Sundarijal in Kathmandu, Godavari in Lalitpur
▪ Use: for household uses and fire fighting
▪ Demand calculation: liters per capita per day (LPCD)
▪ Developed country: more than 500 lpd ( calculated in 700 lpd)
▪ Developing country: less than 50 lpd
▪ Current demand: more than 300 lpd
▪ Current supply: 120 lpd ++
▪ Distribution system: Grid iron system; Dead end system
 Utilities and Services: water supply
▪ Grid iron system > efficient to maintain pressure
▪ Dead end system
> designed in tree branching pattern
> difficult to operate in low pressure mode
> Operate at lower cost
> Easy to add a branch (eg. Like we have in Ktm valley)
 Utilities and Services: waste water
▪ Waste water management> remove contaminants from wastewater
and convert it into an effluent that can be returned to the water cycle.
▪ The treatment process takes place in a wastewater treatment plant
▪ For domestic wastewater (also called municipal wastewater or
sewage), the treatment plant is called a sewage treatment plant.
▪ For industrial wastewater, treatment either takes place in a
separate industrial wastewater treatment plant, or in a sewage
treatment plant (usually after some form of pre-treatment)
▪ Further types of wastewater treatment plants include agricultural
wastewater treatment plants and leachate treatment plants

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Utilities and Services: waste water
▪ Processes commonly used include phase separation (such as
sedimentation), biological and chemical processes (such as
oxidation) or polishing.
▪ The main by-product from wastewater treatment plants is a type of
sludge which is usually treated in the same or another wastewater
treatment plant.
▪ Biogas can be another by-product if anaerobic treatment processes
are used. Some wastewater may be highly treated and reused as
reclaimed water.
▪ The main purpose of wastewater treatment is for the treated
wastewater to be able to be disposed or reused safely.
▪ However, before it is treated, the options for disposal or reuse must
be considered so the correct treatment process is used on the
wastewater
 Utilities and Services: solid waste management
▪ Solid Waste management

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