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  • 1. The Tehri Dam is the highest dam in India and one of the tallest in the world. It is a multi-purpose rock and earth-fill embankment dam on theBhagirathi River near Tehri in Uttarakhand, India. It is the primary dam of the THDC India Ltd. and the Tehri hydroelectric complex. Phase 1 was completed in 2006, the Tehri Dam withholds a reservoir for irrigation, municipal water supply and the generation of 1,000 MW of hydroelectricity. The dam's 1,000 MW pumped-storage scheme is currently under construction. The Tehri Dam has been the object of protests by environmental organizations and local people of the region. In addition to the human rights concerns, the project has spurred concerns about the environmental consequences of locating a large dam in the fragile ecosystem of the Himalayan foothills. There are further concerns regarding the dam's geological stability. The Tehri dam is located in the Central Himalayan Seismic Gap, a major geologic fault zone
  • 2. The main reservoir will sink the old Tehri town and 112 villages around the town, thereby displacing more than 100,000 people. This dam has been the object of intense protests from environmental groups and the people of Tehri and surrounding areas. There have been legal battles over the relocation of more than 1 lakh people. Also, environmental concerns have been raised, as the dam is planned in the Central Himalayan Seismic Gap, a major geologic fault zone (this region was the site of a major earthquake in October 1991). Sunderlal Bahuguna is one of the leaders opposed to this project.
  • 3. The Tehri Dam has been the object of protests by environmental organizations and local people of the region. In addition to the human rights concerns, the project has spurred concerns about the environmental consequences of locating a large dam in the fragile ecosystem of the Himalayan foothills. There are further concerns regarding the dam's geological stability. The Tehri dam is located in the Central Himalayan Seismic Gap, a major geologic fault zone. Resistance to this project has primarily been due to : ●Large scale displacement of local communities. ●Local people often had to give up their land livelihood and their meagre access and contol over resources for the greater good of the nation.
  • 4. With a view to provide maximum assurance of safety, the da m has been designed adopting most stringent design criteria, incorporating certain fea tures which would ensure its safety, in an unforeseen major seismic event. i)A very conservative design slope, with U/S slope of 2.5:1 and D/ S slope of 2.0:1, as against relatively steeper slopes in some recent dams built/proposed in region of very high seismicity. ii)A very wide crest of 20m, which increases to 25m at its contact with abutments, has been provided. (iii)A very liberal free board of 9.5m above FRL has been pro vided to take care of any settlement, slumping due to earthquake and wave action. (iv)The D/S filter as designed is capable of preventing migration of finest particles (clay flocks) in the event of its cracking and would not permit any piping. A zon e of fine (sand) filter has been provided on the U/S face, which in the unlikely event of crac king of core would get washed into cracks and seal them.
  • 5. Water conservation encompasses the policies, strategies and activities to manage fresh water as a sustainable resource to protect the water environment and to meet current and future human demand. Population, household size and growth and affluence all affect how much water is used. Factors such as climate change will increase pressures on natural water resources especially in manufacturing and agricultural irrigation. Developed countries aren’t immune to freshwater problems either. Researchers found a six-fold increase in water use for only a two-fold increase in population size in the United States since 1900.
  • 6. Our ancient religious texts and epics give a good insight into the water storage and conservation systems that prevailed in those days. Over the years rising populations, growing industrialization, and expanding agriculture have pushed up the demand for water. Efforts have been made to collect water by building dams and reservoirs and digging wells ; some countries have also tried to recycle and desalinate (remove salts) water. Water conservation has become the need of the day. The idea of ground water recharging by harvesting rainwater is gaining importance in many cities. At this point, the company is involved in six major projects affecting over 180 villages in Madhya Pradesh, North Gujarat, Tamil Nadu, Karnataka and Maharashtra. The projects are carried out in partnership with non-governmental organisations (NGOs), local community, and government agencies such as NABARD, or directly with state governments.
  • 7. Watershed Management Watershed management is the study of the relevant characteristics of a watershed aimed at the sustainable distribution of its resources and the process of creating and implementing plans, programs, and projects to sustain and enhance watershed functions that affect the plant, animal, and human communities within a watershed boundary. Features of a watershed that agencies seek to manage include water supply, water quality, drainage, stormwater runoff, water rights, and the overall planning and utilization of watersheds. Landowners, land use agencies, stormwater management experts, environmental specialists, water use surveyors and communities all play an integral part in the management of a watershed.
  • 8. • Rainwater harvesting is the accumulation and deposition of rainwater for reuse before it reaches the aquifer. Uses include water for garden, water for livestock, water for irrigation, and indoor heating for houses etc.. In many places the water collected is just redirected to a deep pit with percolation. The harvested water can be used as drinking water as well as for storage and other purpose like irrigation.
  • 9. Hard water is water that has high mineral content (in contrast with "soft water"). Hard drinking water is generally not harmful to one's health, but can pose serious problems in industrial settings, where water hardness is monitored to avoid costly breakdowns in boilers, cooling towers, and other equipment that handles water. In domestic settings, hard water is often indicated by a lack of suds formation when soap is agitated in water, and by the formation of lime scale in kettles and water heaters. Wherever water hardness is a concern, water softening is commonly used to reduce hard water's adverse effects.
  • 10. The water that lathers readily with soaps are called soft water. It describes type of water that contain few or no minerals like calcium(Ca) or magnesium(Mg) ions. The term is usually relative to hard water, which does contain significant amounts of such ions. Soft Water mostly comes from peat or igneous rock sources, such as granite but may also come from sandstone sources, since such sedimentary rocks are usually low in calcium and magnesium. However, soft water does have negative side effects and can be bad for the heart. Thus it should be drunk in moderation if at all.
  • 11. Water softeners break down salt (NaCl) into sodium ions (Na+) and chloride (aka ionic chlorine [ Cl -]) and then release the polluted water into septic systems or sewers. Sewers transport it to treatment plants, which deal with the water and discharge it into groundwater or surface water. Hard water can be softened (have its minerals removed) by treating it with lime or by passing it over an ion exchange resin. The ion exchange resins are complex sodium salts. Water flows over the resin surface, dissolving the sodium. The calcium, magnesium, and other cations precipitate onto the resin surface. Sodium goes into the water, but the other cations stay with the resin. Very hard water will end up tasting saltier than water that had fewer dissolved minerals.
  • 12. •1. Hard water contains minerals- Magnesium and calcium. •Hard water has health benefits and preferred in taste. •It does not form lather with detergents. •It Leaves deposit called “scale”. •Soft water has minimum or no mineral content. •Soft water is preferred for chores and washing related tasks including bathing. •It forms lather with detergents. •Nothing is left.
  • 13. Water resources are sources of water that are useful or potentially useful. Uses of water include agricultural,industrial, household, recreational and environmentalactivities. The majority of human uses require fresh water. 97 percent of the water on the Earth is salt water and only three percent is fresh water; slightly over two thirds of this is frozen in glaciers and polar ice caps.[1] The remaining unfrozen freshwater is found mainly as groundwater, with only a small fraction present above ground or in the air.
  • 14. Tidal power can be extracted from Moon-gravity-powered tides by locating a water turbine in a tidal current, or by building impoundment pond dams that admit-or-release water through a turbine. The turbine can turn an electrical generator, or a gas compressor, that can then store energy until needed. Coastal tides are a source of clean, free, renewable, and sustainable energy. Tidal stream generators (or TSGs) make use of the kinetic energy of moving water to power turbines, in a similar way to wind turbines that use wind to power turbines. Some tidal generators can be built into the structures of existing bridges, involving virtually no aesthetic problems.
  • 15. Hydropower is energy created from moving water. Dammed water passes through a turbine that rotates a generator to create electrical power. This form of energy is relatively inexpensive and has various ranges of environmental impact depending on the facility size. Hydropower has supplied 28 million homes in the U.S. with electricity, equaling 500 million barrels of oil. In 2007, there were 248.3 billion kilowatt hours (kwh) of electricity generated in the U.S. through hydropower, although that’s down from a peak of 356.5 billion kwh in 1997. Pennsylvania currently generates around one percent of total electricity from hydroelectric dams. The state has large potential to enhance hydroelectric generation since it has the second highest mileage of rivers and streams in the nation.
  • 16. Reclaimed water or recycled water, is former wastewater (sewage) that is treated to remove solids and certain impurities, and used in sustainable landscaping irrigation or to recharge groundwater aquifers. The purpose of these processes is sustainability and water conservation, rather than discharging the treated water to surface waters such as rivers and oceans. One example of this is along Calera Creek in the City of Pacifica, CA. [2] The definition of reclaimed water, as defined by Levine and Asaneo, is "The end product of wastewater reclamation that meets water quality requirements for biodegradable materials, suspended matter and pathogens. The definition of reclaimed water, as defined by Levine and Asaneo, is "The end product of wastewater reclamation that meets water quality requirements for biodegradable materials, suspended matter and pathogens.
  • 17. In water's recycling process, waste water, which is full of human, man-made and environmental pollutants, is strained through large grill like screens to remove large debris from the water (rocks, soda cans, among other items). The second stage involves using biological agents to further cleanse the water. The slightly cleaner water flows into an aeration basin, an open "pond" that mixes the water with oxygen. The introduction of tiny microscopic organisms eat up much of the surface's organic contaminants before themselves becoming unusable matter. Then, the water flows into another chamber where chemical agents (like chlorine) destroy any of the micros. The chlorinated water is then mixed with sulfur dioxide, as water high in chlorine or any chemical agent could damage the natural environment. As a result, some treatment plants are using UV radiation to rid the water of the micros. The recycling process is ongoing and flows seamlessly from one stage to another, allowing some water treatment plants to clean more than 50 million gallons of water every day.
  • 18. Using reclaimed water for non-potable uses saves potable water for drinking, since less potable water will be used for nonpotable uses. It sometimes contains higher levels of nutrients such as nitrogen, phosphorus and oxygen which may somewhat help fertilize garden and agricultural plants when used for irrigation. The usage of water reclamation decreases the pollution sent to sensitive environments. It can also enhance wetlands, which benefits the wildlife depending on that eco-system. For instance, The San Jose/Santa Clara Water Pollution Control Plant instituted a water recycling program to protect the San Francisco Bay area's natural salt water marshes. The front yard landscaping and common areas are watered through a fully automatic spray/drip irrigation system and this is the only application authorized for our property. This type of irrigation system should be low maintenance and provide the greatest conservation effort for our landscape.
  • 19. Groundwater is the water located beneath the earth's surface in soil pore spaces and in the fractures of rock formations. The pumpage of fresh ground water in the United States in 1995 was estimated to be approximately 77 billion gallons per day (Solley and others, 1998), which is about 8 percent of the estimated 1 trillion gallons per day of natural recharge to the Nation's ground-water systems (Nace, 1960). From an overall national perspective, the ground-water resource appears ample. Locally, however, the availability of ground water varies widely. Moreover, only a part of the ground water stored in the subsurface can be recovered by wells in an economic manner and without adverse consequences. Nearly onethird of the country is overusing their groundwater reserves.
  • 20. As ageing large-scale surface irrigation schemes have become increasingly inefficient, and farmers have begun growing a wider range of crops requiring water on demand, the number of groundwater wells in India has exploded. In 1960, there were fewer than 100,000 such wells; by 2006 the figure had risen to nearly 12 million. In India, a possible solution to over-use of groundwater is emerging, known as 'groundwater recharge'.
  • 21. In a classic study in 1982, Bredehoeft and colleagues modelled a situation where groundwater extraction in an intermontane basin withdrew the entire annual recharge, leaving ‘nothing’ for the natural groundwater-dependent vegetation community. By year 500 this had reduced to 0%, signalling complete death of the groundwater-dependent vegetation. In 1960, there were fewer than 100,000 such wells; by 2006 the figure had risen to nearly 12 million. In India, a possible solution to overuse of groundwater is emerging, known as 'groundwater recharge' In the first half of the 20th century, the city of San Jose, California, dropped 13 feet from land subsidence caused by over pumping; this subsidence has been halted with improved groundwater management.
  • 22. Water is essential to life on earth. We need water to grow food, keep clean, provide power, control fire, and last but not least, we need it to stay alive! If water is constantly being cleaned and recycled through the earth’s water cycle, why do we need to conserve it? The answer is that people use up our planet’s fresh water faster than it can naturally be replenished. To provide enough clean fresh water for people, water is cleaned at drinking water treatment plants before it is used. And after water is used, it is cleaned again at wastewater treatment plants or by a septic system before being put back into the environment.