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Water

Water. Crisis of a Blue Planet. Freshwater on Earth is dwindling away too fast…. Where in earth all the waters are?. Is the Earth not really watery?. The Earth indeed is WATERY!. 70-75% of the Earth's surface is covered with water. But this is no relief!. 97% of all Earth’s

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Water

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  1. Water Crisis of a Blue Planet Freshwater on Earth is dwindling away too fast….

  2. Where in earth all the waters are? Is the Earth not really watery?

  3. The Earth indeed is WATERY! 70-75% of the Earth's surface is covered with water But this is no relief!

  4. 97% of all Earth’s water is in the oceans Leaving us in a FRESHWATERdeficit situation! It reminds us of what ancient mariner Marco Polo once said Water water everywhere not is single drop to drink!

  5. We have 97% Salty Water only 3% Freshwater Out of the 3% of the fresh water that the Earth has, 2% remains in a frozenstate in glaciers and icecaps of the polar region and Greenland 2% is in Frozen state! South Pole North Pole

  6. As evident, we are now left with just a Meager 1% of freshwater available in liquid form Where in Earth all the liquid freshwater are?

  7. Summarizing pictorially

  8. Comparing with a pie chart How much of Earth's water is usable by humans? Water usable by humans Life on Earth is impossible without Groundwater ! Only this portion! Only 0.3 % ! 99.7 % UNUSABLE

  9. Freshwater are available from different sources Groundwater 29% Lake River 1 % Streams Glaciers at polar ice caps 70 %Unusable

  10. What is Freshwater? 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)

  11. Rivers contribute 0.0002% of the total freshwater 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.

  12. 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

  13. Groundwater exists because of A balancing act of nature called Water Cycle

  14. Groundwater 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.

  15. Groundwater serves many purposes • 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 the • largest 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.

  16. Increasing Groundwater Demand The agricultural sector is the largest user of water globally and accounts for about 70% of the total freshwater abstraction. Presently, industry accounts for 22% of the global 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.

  17. What is Groundwater? 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.

  18. Where is the groundwarer stored 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.

  19. Water Table Aquifer –permeable rock or sediment that transmits water in a quantity great enough to be of use.

  20. One inch of rain on one acre of ground results in 27,192 gallons of water (~100,000 L). 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 aquicludesor confining layers. The Water Table

  21. AQUIFER Is a Geologic unit that can store and transmit enough water to be a significant water resource - Large volume [ in relation to the amounts being removed annually]  - Moderately high porosity  - Facilitate easy movement of water toward a well

  22. 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.

  23. Groundwater and Surface Water are not separate

  24. Groundwater Moves (often very slowly) Water infiltrating the ground is recharge. Groundwater flowing out from the ground is discharge.

  25. Springs 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 likeWakulla andSilver Springsare classified as"magnitude 1"springs which means they each dischargesmore than 65 million gallons of watera day - the equivalent of about1.3 million bathtubs full! SPRINGS Springs Stream Regional Water Table Low permeability layer Groundwater is forced up onto the The surface through openings In the ground

  26. 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.

  27. 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.

  28. Where does groundwater come from? 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.

  29. How water moves down and become groundwater? 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.

  30. Gravity doesn’t pull water all the way to the center of the Earth. Deep in the bedrock there are rock layers made of dense material, such as granite, or material that water has a hard time penetrating, such as clay. These layers may be underneath the porous rock layers and, thus, act as a confining layer to retard the vertical movement of water. Since it is more difficult for the water to go any deeper, it tends to pool in the porous layers and flow in a more horizontal direction across the aquifer confining layer

  31. The same water on Earth is in circulation 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!

  32. Groundwater is precious, almost like Non-Renewable Groundwateris 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”

  33. Pumping exceeds Replenishments 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.

  34. 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 times It’s a jeopardizing situation. What would happen If all the groundwater finish up?

  35. Groundwater Replenishment is too slow! In a 100-year period, a water molecule spends 98 years in the ocean, 20 months as ice, about 2 weeks in lakes and rivers, and less than a week in the atmosphere.

  36. Groundwater Recharge time comparison!

  37. Confined and Unconfined Aquifers

  38. UNSATURATED ZONE 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.

  39. Confined versus unconfined aquifers

  40. Groundwater caters to almost all of our water need Now the cocern is Mankind and animals on Earth may face a grave Ecological disaster 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.

  41. Emerging water shortages • Water crunch usually takes the form of aquiferoverpumping 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.

  42. Concerns Groundwater is scarce. Supply is limited. Earth is overpopulating Over-pumping of groundwater due to overpopulation - Groundwater exhausted places give rise to ‘Water Refugees’ - Croplands become barren when there is no more water left beneath Groundwater supply is dependent on ‘Water Cycle’ - Deep aquifers are not historically rechargeable Pollution of Groundwater

  43. Overpumping 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

  44. Falling Water Table 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.

  45. 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

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