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Crisis of a Blue Planet
Freshwater on Earth is dwindling away too fast….
Leaving us in a FRESHWATER deficit situation!
It reminds us of what ancient mariner Marco Polo once said
Out of the 3% of the fresh water that the Earth has, 2% remains in a frozen state in glaciers and
icecaps of the polar region and Greenland
South Pole North Pole
2% is inFrozenstate!
Water usable by humansOnly this portion!
Groundwater
Lake
River
Streams
Glaciers at polar ice caps
1 %
29%
70 % Unusable
Freshwater is defined as water with less than 0.5 parts per thousand dissolved salts. Freshwater bodies include lakes and ponds, rivers, some bodies of underground water and many kinds of man-made freshwater bodies, such as canals, ditches and reservoirs. The ultimate source of freshwater is the precipitation of atmosphere in the form of rain and snow (Water Cycle)
Free-flowing rivers provide several necessities. They're an important source of drinking water and irrigation for communities. They carry sediments that help create coastal wetland features such as marshes that provide habitats for many animal and plants. They also renew the supply of oxygen that fish and other aquatic life need to breathe.
It is estimated that the volume of groundwater comprises 30.1% of all freshwater resource on earth compared to 0.3% in surface freshwater. 1.5 billion people all over the world depend on Groundwater for drinking water
Groundwater exists because ofA balancing act of nature called
Water Cycle
So the water on which our lives thrive are the ‘freshwater’ provided by GROUNDWATER which is so negligible [ only 0.3% of the total World Water ] in quantity and which we don’t see! These water under the ground are the Groundwater.Amazingly, many people use groundwater but they don't even know it.
The main uses of ground water include:- irrigation uses- drinking water - other public uses- Supplying domestic water to people who do not receive public-supply water. - In many areas, the majority of water used for self-supplied domestic and livestock purposes come from ground-water sources. - Freshground water is used for many important purposes, with thelargest amount going toward irrigating crops. - Local city water agencies withdraw a lot of ground water for public uses, such as for delivery to homes, businesses, and industries, as well as for community uses such as firefighting, water services at public buildings, and for keeping local residents happy by keeping community swimming pools full of water. - Industries and mining facilities also used a lot of ground water.
The agricultural sector is the largest user of water globallyand accounts for about 70% of the total freshwaterabstraction. Presently, industry accounts for 22% of theglobal freshwater consumption. However, water consumption by industries is increasing, and likely to double over the next two decades. In fact, in high income countries, industrial water use already accounts for as much as 59% of the total fresh water consumption. The volume of water consumed per year by
industry is estimated to be 1,170 km3/year by 2025.
People, especially in rural areas, are increasingly dependent on groundwater – up to 2 billion people, a third of the world’s population rely on it.
97%of liquid freshwater is stored underground in aquifers within a few kilometers [mostly 2.4 kms] of the Earth’s surface almost everywhere, beneath hills, mountains, plains, and deserts.
Groundwater is stored in the ground in materials like gravel or sand. It's kind of like the earth is a big sponge holding all that water. Water can also move through rock formations like sandstone or through cracks in rocks. An area that holds a lot of water, which can be pumped up with a well, is called an
aquifer. Wells pump groundwater from the aquifer and then pipes deliver the water to cities, houses in the country, or to crops.
Water Table
Aquifer – permeable rock or sediment that transmits water in a quantity great enough to be of use.
The Water Table
Material saturated with water lies below
the water table.
Materials that conduct water (are
porous and permeable) are
aquifers.
Materials that do not conduct water (are
well-cemented, unfractured, etc.)
are aquicludes or confining layers.
One inch of rain on one acre of ground results in 27,192 gallons of water (~100,000 L).
- Large volume [ in relation to the amounts being removed annually] - Moderately high porosity - Facilitate easy movement of water toward a well
Is a Geologic unit that can store and transmit enough water to be a significant water resource
The water in lakes, rivers, or oceans is called surface water
Groundwater and surface water sometimes trade places. Groundwater can move through the ground and into a
lake or stream. Water in a lake can soak down into the ground and become groundwater.
Groundwater and Surface Water are not separate
Groundwater Moves (often very slowly)
Water infiltrating the ground is recharge. Groundwater flowing out from the ground is discharge.
SPRINGSSprings form where groundwater is forced up and onto the surface through openings in the ground. This is caused by the differences in the slope or "hydraulic gradient" in the aquifer. As rain falls and percolates underground, it exerts pressure on the water already in the aquifer, forcing some to the surface through natural openings. Springs are classified or categorized based on the amount water discharge. For example, in USA, the largest springs like Wakulla and Silver Springs are classified as "magnitude 1" springs which means they each discharges more
than 65 million gallons of water a day - the equivalent of
about 1.3 million bathtubs full!
Groundwater is forced up onto theThe surface through openings
In the ground
Low permeability layer
RegionalWaterTable
SpringsStream
Perched Water Table
Perched aquifers are common, since the geology of the near-surface can be fairly complex. Parts of an aquifer can become perched as a result of slight
variations in the clay content of sediments. Clay-rich sediments tend to be impermeable.
Influent and Effluent
When groundwater flows
into streams they are called
effluent.
When the water table drops,
streams become influent,
and water leaks from the
stream bed into the ground.
Groundwater comes from rain, snow, sleet, and hail that soaks into the ground. The water moves down into the ground because of gravity, passing between particles of soil, sand, gravel, or rock until it reaches a depth where the ground is filled, or saturated, with water. The area that is filled with water is called the saturated zone and the top of this zone is called the water table. The water table may be very near the ground's surface or it may be hundreds of feet below.
Where does groundwater come from?
Gravity: Ground water slowly moves underground, generally at a downward angle (because of gravity), and may eventually seep into streams, lakes, and oceans.
The rocks below our feet: The rock below the Earth’s surface is the bedrock. But Earth’s bedrock consists of 23 many types of rock, such as sandstone, granite, and limestone. Bedrocks have varying amounts of void spaces in them where ground water accumulates and can also become broken and fractured; creating spaces that can fill with water. Some bedrock, such as limestone, is dissolved by water — which results in large cavities that fill with water. Most of the void spaces in the rocks below the water table are filled with water. But rocks have different porosity and permeability characteristics, and water does not move around the same way in all rocks.
Gravity doesn’t pull water all the way to the center of theEarth. Deep in the bedrock there are rock layers made of densematerial, such as granite, or material that water has a hard timepenetrating, such as clay. These layers may be underneath theporous rock layers and, thus, act as a confining layer to retardthe vertical movement of water. Since it is more difficult forthe water to go any deeper, it tends to pool in the porous layersand flow in a more horizontal direction across the aquifer
confining layer
When the water around is looked at, water in streams, rivers, and lakes is seen, which is known as “surface water.”However, there is much more water stored under the ground than on the surface. In fact, some of the
water seen flowing in rivers comes from seepage of ground water into river beds. Water from precipitation continually seeps into the ground to recharge the aquifers,
while at the same time water from underground aquifers continually
recharges rivers through seepage. The water in the apple eaten yesterday may have fallen as rain half-way around the
world last year or could have been used 100 million years ago by Dinosaur to give her
baby a bath!
Groundwater is precious, almost like Non-Renewable
Groundwater is a critical source of domestic water
and industrial water. Because it is part of the limited
budget of fresh (non-saline) water.
It can be viewed as a Non-renewable resource:
It is possible to withdraw it faster
than nature replenishes it through
“WATER CYCLE”
Pumping of groundwater by the world’s farmers exceeds natural replenishment by at least 160
billion cubic metres a year.Agriculture is responsible for most of the depletion of groundwater,
along with up to 70 per cent of the pollution. Both are accelerating.
Pumping exceeds Replenishments
Replenishment of Groundwater is too slow and our activities can
create an imbalance in the hydrologic equation and can
affect the quantity and quality of natural water resources available to current and future generations
This is becoming evident during the recent
timesIt’s a jeopardizing situation. What would happenIf all the groundwater finish up?
In a 100-year period, a water molecule spends 98 years in
the ocean, 20 months as ice, about 2 weeks in lakes andrivers, and less than a week in the atmosphere.
Groundwater Recharge time comparison!
Confined and Unconfined Aquifers
Water at very shallow depths might be just a few hours old; at moderate depth, it may be 100 years old; and at great depth or after having flowed long distances from places of entry, water may be several thousands of years old. Ground water is an important part of the water cycle, and is the part of rainfall that seeps down through the soil until it reaches rock material that is saturated with water. The ground above the water table may be wet to a certain degree, but it does not stay saturated. The unsaturated zone contains air and some water and support the vegetation on the Earth. The saturated zone below the water table has water filled in the tiny pores between rock particles and the cracks of the rocks.
UNSATURATEDZONE
Confined versus unconfined aquifers
Groundwater caters to almost all of our water need
Mankind and animals on Earth may face a grave
Due to rapid depletion of groundwater
The earth's water supply remains constant, but man is capable of altering the cycle of that fixed supply. Population increases, rising living standards, and industrial and economic growth have place greater demands on our natural environment. Our activities can create an imbalance in the hydrologic equation and can affect the quantity and quality of natural water resources available to current and future generations.
• Water crunch usually takes the form of aquifer overpumping and falling water tables. It is often not apparent. Unlike deforestation (which is observable), we come to know about falling water tables only when our wells go dry! The drilling of millions of well has pushed water withdrawals beyond recharge of many aquifers.
• Rivers running dry are more visible. Some rivers even fail to reach sea! Some rivers now just trickling to sea.
Groundwater is scarce. Supply is limited.
Earth is overpopulating
Over-pumping of groundwaterdue to overpopulation
Pollution of Groundwater
Groundwater supply is dependent on ‘Water Cycle’
- Groundwater exhausted places give rise to ‘Water Refugees’
- Croplands become barren when there is no more water left beneath
- Deep aquifers are not historically rechargeable
With traditional animal or human powered water lifting devices it was almost impossible historically to deplete aquifers. But with worldwide spread of powerful diesel and electric pumps during the last half century, overpumping has become a commonplace
Industrial progress has the price to pay!
Earth cannot progress blindly
As the world demand for water has climbed, water tables have fallen in scores of countries,
including China, India, and United States, which together produce nearly half of the
world’s grain. Water tables are falling throughout the northern half of China. As the water table falls, springs and rivers go dry, lakes disappear, and wells dry up. Northern
China is literally drying out.
In India also as the farmers try to feed an
additional 16 million people each year, nearly the population equivalent of
Australia, they are pumping more and more groundwater. This is dropping water tables in
states that together contain a majority of India’s 1 billion people.
Water Table
Water trapped under ground above an impermeable material– Located between the capillary fringe and the
zone of saturation.– Zone of aeration is above where air can enter
the pore spaces– Zone of saturation is
Where the rock is filled
With water
Cone of Depression
Effect of Groundwater Pumping
p.266
A researcher from IIT-Delhi claims that India had breached it water security level way back in 1997-98 by overexploiting the
water resource
Drilling of wells for groundwater extraction
The latest data indicates that under Punjab and Haryana, water tables are falling by up to a meter per year.
The data for monitored wells in northern Gujarat suggest that the water table has fallen from a depth of 15 meters to 400 meters over the last 3 decades. At this point, the harvests of wheat and rice, India’s principal food grains, are still increasing. But within next few years, the loss of irrigation water could override technological progress and start shrinking the harvest, as it is already doing in China.
Groundwater can become polluted, or contaminated. It can become polluted from leaky underground tanks that store petroleum products, leaky landfills, or when people apply too much fertilizer or pesticides on their fields or lawns. When pollutants leak, spill, or are carelessly dumped on the ground they can move through the soil.
Because it is deep in the ground, groundwater pollution is generally difficult and expensive to clean up. Sometimes people have to
find new places to dig a well because their own became contaminated
Groundwater pollution is difficult to clean up
Groundwater Pollution
Pollution in Water
When pollutants enter the ground, they spread out in the groundwater.
If there is no movement of the groundwater, they disperse evenly in all directions.
Sunita Narain of the Centre for Science and Environment in India argues convincingly that a water-based disposal system with sewage treatment facilities is neither environmentally nor economically viable for India. An Indian family of 5, producing 250 litres of exrement in a year and using a water toilet, requires 150,000 litres of water to wash away the wastes.
As currently designed, India’s sewer system is actually a pathogen-dispersal system. It takes a small quantity of contaminated material and use it to make vast quantities of groundwater unfit for human use, often simply discharging it into nearby rivers or streams
Contaminant Flow
Sewage contamination
Salt Water Intrusion
One consequence of
overpumping in
coastal regions is the
encroachment of
saline seawater into
fresh aquifers.
To combat this, many
coastal communities
re-inject wastewater
into coastal aquifers.
Fresh Groundwater contaminated by Saline water near coastal region
Rising sea level due to Global Warming will salinate more groundwater
• Groundwater is available throughout the year (when not depleted), including during the dry season enabling farmers to double crop their land.
• Productivity of groundwater is found to be more than surface water [ Yields of food grains in Punjab for land irrigated with water from wells was 5.5 tons per hectare, whereas, yield with water from canals averaged 3.2 tons per hectare
It takes 1000 tons of water to grow 1 ton of wheat, it takes only 14 tons
to make 1 ton of steel.
Water Refugees!
As per Geological Environmental Monitoring Institute (GEMI) in Beijing, reported that under Hebei Province in the heart of North China Plain, the average level of the deep aquifer dropped 2.9 meters [nearly 10 feet] in 2000. Deep wells [ drilled ] around Beijing now have
to reach 1,000 meters to tap fresh water, adding dramatically to the cost of supply.
Falling water tables, combined with reduced government grain support prices and the loss of farm labour in provinces of China that are rapidly industrializing, are shrinking China’s Grain Harvest. Wheat crops after peaking 123 million tons in 1997, declined to 87 million tons in 2003, a drop of nearly 30 percent
More than one billion people on earth already lack access to fresh
drinking water. If current trend persists, by 2025, the demand
for freshwater is expected to rise to 56%, exceeding the amount
that is currently available.
Groundwater demand will exceed its supply in 2025
By 2000, available freshwater per person dropped to 7,800 cubic
metres from 9,000 cubic metres in 1989, and is
expected to plummet to 5,100 cubic metres per person by 2025, when the
global population is projected to reach 8 billion.
Overpopulation [ Earth’s population would be 1200 crore in 2050 ]
will reduce freshwater availability per person
The world’s six billion people are already using about 54% of all the accessible freshwater contained in
rivers, lakes and underground aquifers. By 2025 the human’s share will be 70%, based on the population
increase.
Groundwater need will increase from 54% to 70% In 2025
If per capita consumption of water resources continues to
rise at its current rate, humankind could be using over 90% of all available
freshwater within 25 years.
Freshwater use will increase upto 90% within next 25 years..NOT TOO LONG TOO FINISH IT UP ENTIRELY !
By 2025, according to projections, more than 2.8
billion people in 48 countries will be facing water stress or scarcity.
Water will become a scarce commodity
By 2050, the number of water short countries soars to 54, affecting 4 billion people, or 40% of the projected global
population. The worst hit areas are in the Middle East, North
Africa and in sub-Saharan Africa.
By 2050, the situation would even worsen
40% of the Global Population would be water starved
Importance of Groundwater in World Water Turnover
Every year the water turnover on Earth involves 577,000 km3
of water. It is the water that evaporates from the oceanic surface
(502,800 km3) and from land (74,200 km3). The same wateramount falls as atmospheric precipitation (on the ocean 458,000
km3 and on land 119,000 km3). The difference betweenprecipitation and evaporation from land surface (119,000 -74,200 = 44,800 km3/year) represents the total runoff of Earth’srivers (42,600 km3/year), and a direct groundwater runoff tothe ocean (2200 km3/year). Base flow for major rivers such as
the Mississippi, Niger, and Yangtze comes from groundwatersources.
Stabilizing world population
Raising land productivity
Raising water storage capacity
Realistic Pricing of water to discourage wastage andencourage efficient water use To decide judiciously on ‘Surface water’ and ‘groundwater’ usageIn India 44 million hectares irrigated by SURFACE WATER and 42Millions hectares irrigated by GROUNDWATER.
Reducing seepage from irrigation canals
Using of low-pressure close to surface sprinklers
Employing ‘drip irrigation’ where water is supplied directly to rootzone of plants and thereby reducing water usage
Rainwater harvesting at local level
Managing waste without discharging it into local environment andAllowing water to be recycled indefinitelyUse of waterless composting toilet
Just on way to our office, we can see the construction of a new concrete Canal which would probably replace the old canal where water meant for irrigation gets seeped down. The concrete canal would prevent that wastage.
Anna Hazare’s EffortRalegaon Siddhi is a village in Parner Taluka of Ahmednagar District , Maharashtra, India. It is considered a model of environmental conservation. Since 1975, led by Anna Hazare, the village has carried out programs like - tree planting- terracing to reduce soil erosion and - digging canals to retain rainwater. - Fixing tankIn 1975 the village was afflicted by drought. The village tank could not hold water as the embankment dam wall leaked. Work began with the percolation tank construction. Once this was fixed, the seven wells below filled with water in the summer for the first time.
Now the village has water year round, as well as a grain bank, a milk bank, and a school. There is no longer any poverty.
Rainwater Harvesting
Rainwater harvesting is the gathering, or accumulating and storing, of rainwater. Traditionally, rainwater harvesting has been practiced in arid and semi-arid areas, and has provided drinking water, domestic water, water for livestock, water for small irrigation and a way to replenish ground water levels.
Arvari river is a small river in Rajasthan. It flows through the Alwar District of Rajasthan.
Due to Water harvesting methods, the river has become a perennial river from seasonal one
Rajendra Singh’s effortRajendra Singh is a well known water conservationist from Alwar, Rajasthan in India. He won the Ramon Magsaysay Award for community leadership in 2001 for his pioneering work in water management. He is the founder of an NGO called Tarun Bharat Sangh. The NGO has been instrumental in fighting the slow bureaucracy and has helped villagers take charge of water management in their area,
through the use of check dams and other time-tested as well as path-breaking techniques. This NGO played a vital role in reviving Arvari River
Check Dam
If all the world’s water were fit into a gallon jug, the fresh water available for us to use
would equal only about oneTablespoon!
In a five-minute shower we use 95 to 190 litres of water.
To brush our teeth we use 7.5 litres of water.
In the future wars in the Middle East will more likely be fought
Over water than over oil ! !
End of Slide Show
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