- Most of Earth's water is saltwater found in oceans, while only 3% is freshwater. Of this freshwater, over two-thirds is frozen in glaciers and ice sheets.
- Water is continually cycled through the Earth in the hydrological cycle between oceans, atmosphere, and land via evaporation, condensation, precipitation, and infiltration. This cycle provides freshwater for human and ecosystem uses.
- Groundwater makes up about 96% of unfrozen freshwater and provides 25-40% of the world's drinking water by flowing through aquifers. However, groundwater quality can be impacted by natural and human-caused contaminants.
2. The Water in our lives Where is Earth’s water? How much water is there? How much water is consumed in our daily lives How much of the drinking water is free of contamination What measures should we take to prevent wastage of water
3. Where is Earth’s Water ? There is no shortage of water on Earth. Most of our planet is covered by water but very little of that water is available for humans to drink.Our “blue planet” is dominated by oceans that stretch across some two-thirds of its surface. These massive bodies of saltwater hold almost all the water on Earth. Less than three percent of the planet’s water exists as freshwater and not all of it is accessible for human use. In fact, more than two-thirds of the planet’s freshwater is not even liquid—it’s frozen in glaciers in places like the Antarctic and Greenland ice sheets. All Earth’s water Ocean 97% Fresh water 3% Surface Water 1. Rivers: 2% 2. Swamps: 11% 3. Lakes: 87% Fresh water Icecaps/Glaciers: 68.7% 2. Ground: 30.1% 3. Other: .9% 4. Surface: .3%
4. Water on move Water is continually moving around, through, and above the Earth as water vapor, liquid water, and ice. In fact, water is continually changing its form. The Earth is pretty much a "closed system," like a terrarium. That means that the Earth neither, as a whole, gains nor loses much matter, including water. The hydrological cycle moves water from the atmosphere to the Earth and back again in a process of perpetual motion powered by energy from the sun and by gravity. The cycle’s processes provide the water that flows through rivers, lakes, reservoirs, and aquifers from which many people get their drinking water. Indeed, the water cycle makes life on Earth possible. Precipitation: When these water droplets (or ice crystals) become to large to stay suspended in the air, they fall as precipitation—the rain and snow that eventually returns most atmospheric water to the Earth. Condensation: Water vapor cools as it expands and encounters cooler temperatures in the atmosphere. It may then condense into tiny water droplets, forming clouds. This process is called condensation. Infiltration: Instead of evaporating, some water that lands on continents runs off into rivers, streams, and lakes. The rest sinks through the soil to join underground aquifers. This is known as infiltration, or recharge. Evaporation: Solar energy heats surfaces (the oceans, lakes, reservoirs, plants and trees, and the land surface itself) and creates water vapor that returns to the atmosphere by evaporation and transpiration
5. Water is one of our most natural resources. Without it, there would be no life on earth.
6. Groundwater About 96 percent of all unfrozen fresh water is found below the Earth’s surface and is known as groundwater. Groundwater systems globally provide 25 to 40 percent of the world’s drinking water. Groundwater represents an enormous resource that can only be managed through an understanding of the different types of aquifers and their rates of renewal. Aquifers that are located close to the surface are often intimately connected with surface water systems. They may be replenished directly by infiltration of precipitation and sometimes surface runoff, and may discharge to water bodies such as streams and lakes. When such aquifers are drawn down by pumping, they can cause a decrease in river flow, resulting in shortages of drinking water, water for agriculture, or water for the aquatic ecosystem. Deeper aquifers may also be replenished indirectly by water slowly leaking downward from shallower aquifers Aquifers, particularly those close to the surface, are often connected with surface water systems. They may be replenished by recharge from precipitation Renewable Groundwater
7. Groundwater quality Water is such an excellent solvent it can contain lots of dissolved chemicals. And since groundwater moves through rocks and subsurface soil, it has a lot of opportunity to dissolve substances as it moves. For that reason, groundwater will often have more dissolved substances than surface water will.Underground water can get contaminated from industrial, domestic, and agricultural chemicals from the surface. This includes chemicals such as pesticides and herbicides that many homeowners apply to their lawns. Contaminants can be natural or human-induced Naturally occurring contaminants are present in the rocks and sediments. As groundwater flows through sediments, metals such as iron and manganese are dissolved and may later be found in high concentrations in the water. Industrial discharges, urban activities, agriculture, ground-water pump age, and disposal of waste all can affect ground-water quality. Contaminants from leaking fuel tanks or fuel or toxic chemical spills may enter the groundwater and contaminate the aquifer
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9. Bacteria's
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11. Bacteria in Water Bacteria are common single-celled organisms and are a natural component of lakes, rivers, and streams. Most of these bacteria are harmless to humans; however, certain bacteria, some of which normally inhabit the intestinal tract of warm-blooded animals, have the potential to cause sickness and disease in humans. High numbers of these harmless bacteria often indicate high numbers of harmful bacteria as well as other disease-causing organisms such as viruses and protozoans.
12. Safe Drinking water is Essential Drinkable water is a precious commodity. Most of Earth’s water is seawater. About 2.5 percent is freshwater—and two-thirds of that is frozen in ice caps and glaciers Protecting and managing freshwater sources, above and below ground, is an essential task.People can’t create more water. But, by managing sources and distribution systems, they can maximize the amount of available water and make the most out of every drop.
17. The Indicators The Indicators pH :pH is a measurement of the acidic or basic quality of water. The pH scale ranges from a value of 0 (very acidic) to 14 (very basic), with 7 being neutral. Most aquatic animals prefer a range of 6.5 to 8.0. They are adapted to a specifi c pH level and may die, stop reproducing or move away if the pH of the water varies beyond this range. Low pH can also allow toxic compounds to become more available to aquatic plants and animals. This can produce conditions that hurt aquatic life. pH can be affected by acid rain, wastewater discharges, drainage from mines and the type of rock naturally found in the area. Temperature :Aquatic animals (e.g. stream insects, trout and salmon) are sensitive to changes in water temperature and require a certain temperature range to survive and thrive. If water temperature is outside that range for a long time, organisms can be stressed and die. Temperature also erosion, urban runoff, algal blooms and bottom sediment disturbances, which can be caused by boat traffic and abundant bottom feeding fish.
27. The _______________________can be used before the purification process begins. Some contaminants,such as oil, can be removed easily, after they have reached the bottom of the tank. Distillation Method Filtration Method Settling Method UV Radiation Method
28. The UV Radiation Method can be use as an effective viricide and bactericide.Disinfection using this method is commonly used in wastewater treatment applications and is finding an increased usage in drinking water treatment. Many bottlers of spring water use this method equipment to sterilize their water.
29. _______________________ is highly effective in removing several impurities from water such as total dissolved solids (TDS), turbidity, asbestos, lead and other toxic heavy metals, radium, and many dissolved organics Flocculation process Deionization Method Reverse Osmosis Method
30. Settling Method isused as a germicidal treatment for water, effectively removes most particles, pyrogens, microorganisms, and colloids above the rated size.
