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Water Resources
Submitted to:
Mehedi Iqbal
Assistant professor
Department of Geography & Environment
Group B
 Monira Akter Roll - 483
 Khairun Nessa Roll - 491
 Sumaiya Alamgir - 498
 Rayhan Imam -513
 Abdullah Al Fahad - 520
 Tarek Abdullah Aziz Roll -527
 Noman Rahman - 535
 A K M Kamrul Hasan Shourov -2082
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A resource is a source or supply from which benefit is
produced. Typically resources are materials, energy,
services, staff, knowledge, or other assets that are
transformed to produce benefit and in the process may
be consumed or made unavailable. Benefits of resource
utilization may include increased wealth or wants,
proper functioning of a system, or enhanced well being.
Resources have three main characteristics:
1.Utility,
2.Limited availability,
3.Potential for depletion or consumption.
Resources have been variously categorized:
 Biotic versus Abiotic,
 Renewable versus Non-renewable,
 Potential versus Actual
 Resources
can be broadly classified on bases upon their
availability they are
1.Renewable and
2.Non renewable resources
 On the basis of origin they can be classified as
1.Natural Resources
2.Human Resources
 Natural
Resources
1. Land,
2.Water,
3.Forests,
4.Mineral and energy
 Human Resources:
1.Population,
2.Labor force,
3.Health and Education
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Water resources are sources of water that are useful or
potentially useful to humans. It is important because it
is needed for life to exist. The majority of human uses
require fresh water.
Fresh water is a renewable resource, yet the world’s
supply of groundwater is steadily decreasing.
Flowing
artesian well
Precipitation
Well requiring a pump
Evaporation and transpiration
Evaporation
Confined
Recharge Area
Runoff
Aquifer
Stream
Infiltration Water table
Infiltration
Lake
Unconfined aquifer
Less permeable material
such as clay
Confined aquifer
Confirming permeable rock layer
About 2/3 of world surface is covered with water. Out of the
total available water 75%is used for agriculture,20% for
industrial usage.
Ground water:
9.86% of fresh water is ground water and it is35-50% greater
than surface water.
 Aquifer: The layer of soil which is permeable has the
ability to store water is called an aquifer. It is generally
made up of gravel, sand etc.
 Unconfined aquifer: it is covered by permeable layer. The
recharge of this layer is by rainfall or snowmelt
 Confined aquifer: sandwiched between impermeable
layers. The recharge is through unconfined aquifer layers.
Surface Water:
1. Standing water bodies: A) Lakes B) Reservoirs
C)Estuaries
2. Flowing Water Bodies: A) Streams B) Rivers
3. Under ground water
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It is the renewable natural resources of Bangladesh.
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There area total of 230 rivers in Bangladesh. throughout the
country there are Bills, Haors and Lakes that meet the need
of drinking, bathing and irrigating water.
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Two main rivers of the country are the Brahmaputra and the
Gangas account for more than 80% of stream flows.
In Bangladesh, the sources of water are surface water
and ground water. Both the sources may be fresh or
saline.
Surface water sources are categorized as ,
• Rainfall,
• Trans-boundary flow,
• Water on standing water bodies (water storage in
reservoir, water bodies such as river, lake and pond),
• Water on seasonal wetlands, and
• In-stream storage
These are describes below:
i)
Rainfall
Average annual rainfall of the country is about 2360 mm (19601997). About 20% of the average annual rainfall occurs in dry
season (November-May) in northwest region but the monthly
distribution of this amount is highly uneven.
ii)Transboundary flow
Bangladesh shares 57 transboundary rivers, 54 incoming from
India, 3 from Myanmar. Among the rivers, the Ganges, the
Brahmaputra and the Meghna drain about 1.08 million sq.km.,
0.58 million sq.km. and 0.09 million sq.km. respectively. Total
annual volume of water that enters into the country from the
trans-boundary rivers is about 1000 billion cubic meter
iii) Water on standing water bodies
In addition to natural rivers, water is retained in localized
low pockets (beels/baors) and ponds in dry season.
Kapatai lake is the lonely reservoir in the country that has
storage capacity. Total volume of such standing water
bodies is about 0.61 billion cubic meter
iv) In-stream water storage
The numerous channels criss-crossing the entire country,
in flowing stage, store water till these are completely dries.
Estimated volume of channel storage is of the order of 0.5
billion cubic meters.
v) Water on seasonal wetlands
Floodplains (about 80% of the total area of the
country) become seasonal wetlands during monsoon
(July-October) because of slow drainage of huge transboundary flow and local rainfall excess.
1.The seasonal wetlands remain inundated from a few
days to as long as several months (May-November).
Estimated volume of water stored in these seasonal
wetlands/floodplains is about 2.69 billion cubic meter.
2.This seasonal storage has virtually no contribution
during dry season
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Food and water are two basic human needs. However,
global coverage figures from 2002 indicate that, of
every 10 people:
Roughly 5 have a connection to a piped water supply
at home (in their dwelling, plot or yard);
3 make use of some other sort of improved water
supply, such as a protected well or public standpipe;
2 are unserved;
In addition, 4 out of every 10 people live without
improved sanitation
At Earth Summit 2002 governments approved a Plan of
Action to:
1.
Halve by 2015 the proportion of people unable to reach or
afford safe drinking water. The Global Water Supply and
Sanitation Assessment 2000 Report (GWSSAR) defines
"Reasonable access" to water as at least 20 liters per
person per day from a source within one kilometer of the
user’s home.
2.
Halve the proportion of people without access to basic
sanitation. The GWSSR defines "Basic sanitation" as
private or shared but not public disposal systems that
separate waste from human contact
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In 2025, water shortages will be more prevalent among
poorer countries where resources are limited and
population growth is rapid, such as the Middle East,
Africa, and parts of Asia. By 2025, large urban and
pre-urban areas will require new infrastructure to
provide safe water and adequate sanitation. This
suggests growing conflicts with agricultural water
users, who currently consume the majority of the water
used by humans.
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Generally speaking the more developed countries of North
America, Europe and Russia will not see a serious threat
to water supply by the year 2025, not only because of their
relative wealth, but more importantly their populations will
be better aligned with available water resources. North
Africa, the Middle East, South Africa and northern
China will face very severe water shortages due to physical
scarcity and a condition of overpopulation relative to their
carrying capacity with respect to water supply. Most of
South America, Sub-Saharan Africa, Southern China
and India will face water supply shortages by 2025; for
these latter regions the causes of scarcity will be economic
constraints to developing safe drinking water, as well as
excessive population growth.
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1.6 billion people have gained access to a safe water
source since 1990. The proportion of people in
developing countries with access to safe water is
calculated to have improved from 30 percent in 1970 to
71 percent in 1990, 79 percent in 2000 and 84 percent
in 2004. This trend is projected to continue.
Water scarcity is the lack of fresh
water resources to meet water demand. It affects
every continent and was listed in 2015 by
the World Economic Forum as the
largest global risk in terms of potential impact
over the next decade.
Water scarcity can result from two mechanisms:
 Physical (absolute) water scarcity
 Economic water scarcity
Physical water scarcity results from inadequate natural
water resources to supply a region's demand. Around one
fifth of the world's population currently live in regions
affected by Physical water scarcity, where there is
inadequate water resources to meet a country's or regional
demand, including the water needed to fulfill the demand
of ecosystems to function effectively.
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Economic water scarcity is caused by a lack of
investment in infrastructure or technology to draw
water from rivers, aquifers or other water sources, or
insufficient human capacity to satisfy the demand for
water. One quarter of the world's population is
affected by economic water scarcity. Economic water
scarcity includes a lack of infrastructure, causing the
people without reliable access to water to have to travel
long distances to fetch water, that is often contaminated
from rivers for domestic and agricultural uses.
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Two-thirds of the global population (4.0 billion
people) live under conditions of severe water
scarcity at least 1 month of the year.
Half a billion people in the world face severe
water scarcity all year round
Half of the world’s largest cities experience
water scarcity.
Technically, there is a sufficient amount of freshwater on a
global scale, for humanity to get by. However, due to
unequal distribution (exacerbated by climate change)
resulting in some very wet and some very dry geographic
locations, plus a sharp rise in global freshwater demand in
recent decades, humanity is facing a water crisis, with
demand expected to outstrip supply by 40% in 2030, if
current trends continue.
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Water Scarcity in Bangladesh:
The WHO estimates that 97% of the people of
Bangladesh have access to water and only 40% percent
have proper sanitation
With a staggering 60% of the population that has to
endure unsafe drinking water
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The availability of this water greatly fluctuates throughout
the year as the warmer season brings massive amounts of
water in frequent monsoons and the cooler season brings
drought.
The infrastructure cannot adequately deal with the barrage
of water in monsoon season so the water is not saved for the
drier months.
The great rivers (Brahmaputra, Meghna, and Ganges) all
originate in other countries and the amount of water that
eventually gets to Bangladesh is greatly limited by the
booming populations of China and India
Only 7% of the total land that creates the watersheds for
these rivers is in Bangladesh. Therefore the Bengalis have
very little control over how much water they receive from
these sources.
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The problem is the rising salinity of the water, which has many contributing
factors. One of these factors is the construction of the Farraka Barrage, a
structure in India that diverts water from the Ganges to irrigate Indian soil.
This decreases the flow of the Ganges thereby causing the salinity to increase.
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Salinity is also rising due to the sheer number of shrimp farms in various
bodies of fresh water
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Climate change has also caused rising sea levels which are claiming precious
water from freshwater river deltas. This increase in salinity affects the soil and
the quality of the ground water.
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Not only is the potable water limited but the groundwater, which is used by
nearly 90% of the population, is also contaminated with arsenic. According to
the WHO, the levels of arsenic have contributed to the largest mass poisoning
in history, affecting an estimated 30-35 million people in Bangladesh
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As a result, the Bangladeshi government is trying to
improve the infrastructure to improve rainwater
capture and access to safe drinking water.
Contaminated wells have been marked to warn the
people away but the painted markers are fading and
more than 100,000 safe water points have been
created. New arsenic treatment technologies are also
being investigated by the Bangladesh Council of
Scientific and Industrial Research.
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Water in agriculture: water plays the most important role in
agriculture. Agriculture is impossible without irrigation
throughout the crop season. Irrigation ensures proper plant
growth.
Water for Municipal use: Lifestyle of the inhabitants and
their economic conditions affect the water use within the
home in different parts of the country. Municipal; demand
includes water for domestic purposes. Commercial uses, street
washing, lawn and garden irrigation, fire protection.
Balancing the ecosystem: Water is not only important for
human beings but also plays an important role to balance the
entire ecosystem by various ways; by its presence in the
atmosphere it absorbs the sun’s heat. The rain water scours the
hills and carries the sediments into rivers, valley etc.
percolating water into rock crusts takes part in the formation
of mineral deposits. In polar regions, water in the form of the
caps influences climatic and geographical changes.
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Water for industries: water is used in huge quantities in the
industries like steel industry, chemicals, fertilizers, textiles,
cement, electricity, petrochemicals & paper. Mining, food etc.
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Water for power: Thermal power plants also requires large
volume of water for the purpose of cooling and disposal of fly ash.
Water is used in thermal power generation.
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Water for fish, wildlife and recreation: Fish, wildlife and
recreation facilities play an important role in nation’s life and
adequate water supplies for their continued development &
important. Swimming, boating, fishing is the important outdoor
recreational activities which are impossible without water.
Uses of water- Different types
 Consumptive use: water is completely utilized and it is not
reused. Ex. In domestic application.
 Non-Consumptive use: Water is not completely utilized
and it is reused. Ex. Hydro power plant.
Other important uses of water:
 Used for domestic purposes. Ex. Drinking, Cooking.
 Used for commercial purposes. Ex. Hotels
 Used for irrigation (60-70%)
 Used for industrial operations (20-30%). Ex. Refineries
 Used for moderating climate and diluting pollutants.
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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
Over utilization of ground water:
Over utilization of water leads to,
 Rapid depletion of water resources,
 Ground subsidence,
 Lowering of water table
 Water logging
Effects of over utilization of ground water:
Reasons: Economic development, rapid industrial growth
and population explosion.
The use of ground water and surface water rates
which are higher than that of recharge ultimately leads to
 Water scarcity
 Water logging
 Salinity
 Alkalization
 Water pollution
Groundwater Pollution:
1.Agricultural products
2.Underground storage tanks
3.Landfills
4.Septic tanks
5.Surface impoundments
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Industrial causes of water pollution: Industries cause
huge water pollution with their activities. These come
mainly from: 1.Sulphur 2. Asbestos 3. Lead and
Mercury 4. Nitrates & Phosphates
Oil Pollution by Oil Industries: Routine shipping,
run-offs and dumping of oils on the ocean surfaces
happen everyday. Oil spills make up about 12% of the
oil that enters the ocean. Because oil does not dissolve,
it stays on the water surface and suffocates fish.
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Atmospheric: Atmospheric deposition is the pollution of
water bodies caused by air pollution. Each time the air is
polluted with sulphur dioxide and nitrogen oxide, they mix
with water particles in the air and form a toxic substance.
Ocean and marine dumping: Again, think of the rubbish
we all make each day. Paper waste, food waste, plastic,
rubber, metallic and aluminium waste. In some countries,
they are deposited into the sea. All these waste types take
time to decompose. When these end up in the sea, they
harm sea animals and cause a lot of water animal deaths
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Other causes of surface water pollution: Apart from
the industrial causes of water pollution, as we saw in
the previous page, here are some more:
Sewage and waste water: Everyday, we cook, do
laundry, flush the Toilet, wash our cars, shower and do
many things that use water.
Dealing with water pollution is something that everyone
(including governments and local councils) needs to get
involved with. Here are a few things you can do to help.
Learning about the issue (like you are doing) is the greatest
and most important step to take.
Here are a few more:
1.Never throw rubbish away anyhow.
2. Do not throw chemicals, oils, paints and medicines down
the sink drain, or the toilet.
3. If you live close to a water body, try to plant lots of trees
and flowers around your home.
4.Buy more environmentally safe cleaning liquids for use at
home and other public places.
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Many governments have very strict laws that help
minimize water pollution. In many developed cities,
waste or sewage treatment is very efficient, and
designed to minimize pollution of water bodies. There
are also lots of organizations and groups that help
educate people on the dangers of water pollution. It is
always great to join these groups, because they
regularly encourage other members of their
communities to have a better attitude towards water.
For Example: Liquid Waste (Sewage/Wastewater)
Treatment
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Population Growth: In 2000 the world population was
6.2 billion. The UN estimates that by 2050 there will be an
additional 3.5 billion people with most of the growth in
developing countries that suffer water stress. Thus, water
demand will increase unless there are corresponding
increase in water conservation and recycling of this vital
resource.
Expansion of business activity: Business activity ranging
from industrialization to services such as tourism and
entertainment continues to expand rapidly. This expansion
requires increased water services including both supply
and sanitation, which can lead to more pressure in water
resources and natural ecosystem.
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Rapid Urbanization: The trends towards urbanization is acceleration.
Urbanization requires significant investment in water infrastructure in order
to deliver water to individuals and to process the concentrations of
wastewater- both from individuals and from business. These polluted and
contaminated waters must be treated or they pose unacceptable public
health risks.
Climate change: Climate change could have significant impacts on water
resources around the world because of the close connections between the
climate and hydrological cycle. Rising temperatures will increase
evaporation and lead to increases in precipitation, though there will be
regional variations in rainfall. Both droughts and floods may become more
frequent in different regions at different times, and dramatic changes in
snowfall and snow melt are expected in mountainous areas.
Pollution: Many pollutants threaten water supplies, but the most wide
spread, especially in developing countries, is the discharge of raw sewage
into natural waters; this method of sewage disposal is the most common
method in underdeveloped countries, but also is prevalent in quasi
developed countries such as China. India. Nepal and Iran.
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Water conservation refers to reducing the usage of
water and recycling of waste water for different
purposes such as cleaning, manufacturing and
agricultural irrigation.
It is a practice in which people, companies and
governments attempt to reduce their water usage.
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When washing dishes by hand, don’t let the water run while
rinsing. Fill one sink with wash water and the other with rinse
water.
Run your clothes washer and dishwasher only when they are
full. You can save up to 1,000 gallons a month.
Water your lawn and garden in the morning or evening when
temperatures are cooler to minimize evaporation.
Wash your fruits and vegetables in a pan of water instead of
running water from the tap.
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Adjust sprinklers so only your lawn is watered and not
the house, sidewalk, or street.
Some refrigerators, air conditioners and ice-makers are
cooled with wasted flows of water. Consider upgrading
with air-cooled appliances for significant water
savings.
Plant in the fall when conditions are cooler ad rainfall
is more plentiful.
Use the garbage disposal sparingly. Compost vegetable
food waste instead and save gallons every time.
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Water management is the control and movement of
water resources to minimize damage to life and
property and to maximize efficient beneficial use. Good
water management systems make the most efficient use
of limited water supplies for agriculture.
Drainage management involves water budgeting and
analysis of surface and sub-surface drainage system.
Sometimes water management involves changing
practices, such as groundwater withdrawal rates, or
allocation of water to different purposes.
Physical problems
 Poorly developed water supply and wastewater
treatment facilities.
 Incomplete water monitoring systems.
 Water Pricing problems
 Lower water prices-> excessive water use in agriculture
 Organizational problems
 Integrated water resources management has not been
fully implemented in most of Asia and the pacific.
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There are some regulatory authorities to implement and
supervise the noted activities according to various
policies and acts on water. Some of the regulatory bodies
are
1.Ministry of Water Resources,
2.Bangladesh Water Development Board (BWDB),
3.Water Resources Planning Organization (WARPO),
4.River Research Institute (RRI),
5.Joint Rivers Commission (JRC),
6. Dhaka WASA etc
•Existing Policies for Water Management Bangladesh has
various national policies for different key sectors to accelerate
the balanced way of development.
•There are several policies and acts for formulating the rules
and regulations on general usage on water.
The major policies and acts are:
a.National Water Policy (1999);
b. Coastal Zone Policy (2005);
c. Coastal Development Strategy (2006);
d. National Water Management Plan: Development Strategy
(2011);
e. Bangladesh Water Act 2013.
The water policy lays down the broad principles of development of water
resources and their rational utilization under several challenges:
•Alternating flood and water scarcity during the wet and the dry seasons;
•Ever-expanding water needs of a growing economy and population;
•Massive river sedimentation and bank erosion;
•Providing total water quality management;
•The lack of control over trans boundary rivers;
•The difficulty of managing the deltaic plain;
•The virtual absence of unsettled land for building water structures.
The policy and strategies, however, keep a continuous direction on the
way of serving best welfare to the common people. But that is a small part
of achieving the common interest as because it is by and large dependent
on the executing mechanism of the regulations by practice. It is purely the
responsibilities of the governmental authority to run the proper activities
according to the policy in view of serving the common people. Otherwise,
the policies remain only on the papers.
•A paramount issue is water-its availability, quality and
management.
•Extensive hydrological information is necessary to develop water
resources and protect them.
•Water resource management is a very important issue from several
angles such as Development of water bodies for future •Protection
of available water bodies from pollution and over exploitation and
Prevent water bodies from contamination . .
Role of hydrology for water resources management
• Estimation of water resources availability
• Estimation and reduction of hydrological risks
• Development of hydrological scenarios
• Ensure proper information to decision maker
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www.britannica.com
www.wikipedia.org
www.banglapedia.org
Thanks to all
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