NAME: DIPTY AGARWALCLASS: 10SECTION: BROLL NUMBER:11REGISTRATION NUMBER: B114084140067SUBJECT: SCIENCE

BIOLOGY

WATER RECYCLING

INTRODUCTION

Reclaimed water or recycled water is former wastewater that is treated to remove solids and certain impurities, and used is 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 water such as rivers and oceans. In some cases, recycled water can be used for streamflow augmentation to benefit ecosystems and improve aesthetics

How Can Water Recycling Benefit Us?Water recycling provides enormous environmental benefits. It also provides an additional source of water for various purposes. This a list of some benefits that water recycling can present.•Water recycling decreases the extraction of water form sources that may be dwindling and may stop being viable as habitats for valuable and endangered wildlife.•Recycling wastewater can decrease the discharge of effluents that may damage and pollute the ecosystems of the sensitive bodies of water.•Recycled water can be used to create new wetlands or to enhance and improve the quality of existing ones.•Water recycling can reduce and prevent pollution by leaving damaging pollutants at the treatment plant.

LIMITATIONSWith mounting water issues, municipalities are under stress to provide water (potable and non-potable) to industrial, commercial, and residential segments. Though wastewater recycling and reuse is an option to meet water requirements, some factors are limiting its use, such as: • High price sensitivity towards advanced wastewater treatment systems • Negative perception about wastewater recycling • Lack of technological awareness and skilled manpower • Fragmented nature of the market • Weak enforcement of regulations and policies

Why recycle water?Increasing population means that the demand for water is increasing. To ensure that we have enough water to meet our present and future needs, we need to conserve water and expand the use of recycled water.

NAME: DIPTY AGARWALCLASS: 10SECTION: BROLL NUMBER:11REGISTRATION NUMBER: B114084140067SUBJECT: SCIENCE

CHEMISTRY

HARDNESS OF WATER

INTRODUCTIONHard water is any water containing an appreciable quantity of dissolved minerals. Soft water is treated water in which the only cation (positively charged ion) is sodium. The minerals in water give it a characteristic taste. Some natural mineral waters are highly sought for their flavor and the health benefits they may confer. Soft water, on the other hand, may taste salty and may not be suitable for drinking.

Water's hardness is determined by the concentration of multivalent cations in the water. Multivalent cations are cations (positively charged metal complexes) with a charge greater than 1+. Usually, the cations have the charge of 2+. Common cations found in hard water include Ca2+ and Mg2+. These ions enter a water supply by leaching from minerals within an aquifer. Commoncalcium-containing minerals are calcite and gypsum. A common magnesium mineral is dolomite (which also contains calcium). Rainwater and distilled water are soft, because they contain fewions.[2]

The following equilibrium reaction describes the dissolving/formation of calcium carbonate scale:CaCO3 + CO2 + H2O ⇋ Ca2+ + 2HCO3

−

Calcium carbonate scale formed in water-heating systems is called limescale.

EFFECTSWith hard water, soap solutions form a white precipitate (soap scum) instead of producing lather, because the 2+ ions destroy the surfactant properties of the soap by forming a solid precipitate (the soap scum). A major component of such scum is calcium stearate, which arises from sodium stearate, the main component of soap:2 C17H35COO- + Ca2+ → (C17H35COO)2CaHard water also forms deposits that clog plumbing. These deposits, called "scale", are composed mainly of calcium carbonate (CaCO3), magnesium hydroxide (Mg(OH)2), and calcium sulfate (CaSO4)

SOFTENINGIt is often desirable to soften hard water. Most detergents contain ingredients that counteract the effects of hard water on the surfactants. For this reason, water softening is often unnecessary. Where softening is practiced, it is often recommended to soften only the water sent to domestic hot water systems so as to prevent or delay inefficiencies and damage due to scale formation in water heaters. A common method for water softening involves the use of ion exchange resins, which replace ions like Ca2+ by twice the number of monocations such as sodium or potassiumions.

NAME: DIPTY AGARWALCLASS: 10SECTION: BROLL NUMBER:11REGISTRATION NUMBER: B114084140067SUBJECT: SCIENCE

PHYSICS

WATER AS AN ENERGY RESOURCE

WATER AS AN ENERGY RESOURCE

TIDAL ENERGYTidal power is the only form of energy which derives directly from the relative motions of the Earth–Moon system, and to a lesser extent from the Earth–Sun system. The tidal forces produced by the Moon and Sun, in combination with Earth’s rotation, are responsible for the generation of the tides..Tidal power, also called tidal energy, is a form of hydropower that converts the energy of tides into electricity or other useful forms of power.Although not yet widely used, tidal power has potential for future electricity generation. Tides are more predictable than wind energy and solar power. Among sources of renewable energy, tidal power has traditionally suffered from relatively high cost and limited availability of sites with sufficiently high tidal ranges or flow velocities, thus constricting its total availability. However, many recent technological developments and improvements, both in design (e.g. dynamic tidal power, tidal lagoons) and turbine technology (e.g. new axial turbines, crossflow turbines), indicate that the total availability of tidal power may be much higher than previously assumed, and that economic and environmental costs may be brought down to competitive levels.Because the Earth’s tides are caused by the tidal forces due to gravitational interaction with the Moon and Sun, and the Earth’s rotation, tidal power is practically inexhaustible and classified as a renewable energy source.

HOW TIDE GENERATES:Tidal  energy  is  generated  by  the  relative  motion  of  the  water  which  interact  via  gravity.  Periodic changes  of water  levels,  and  associated  tidal  currents,  are  due  to  the  gravitational  attraction  by  the  Sun  and Moon. The  magnitude  of  the  tide  at  a  location  is  the  result  of  the  changing  positions  of  the Moon  and  Sun relative to the Earth, the effects of Earth rotation, and the local shape of the sea floor and coastlines. Because  the Earth’s  tides are caused by  the  tidal  forces due  to gravitational  interaction with  the Moon and Sun, and the Earth’s rotation,  tidal power is practically inexhaustible and classified as a  renewable energy source. A  tidal  generator  uses  this  phenomenon  to  generate  electricity. The  stronger  the  tide,  either  in water level height or tidal current velocities, the greater the potential for tidal electricity generation..LocationHistorically, tidal mills were usually built on inlets branching off tidal estuaries. An estuary is a wide part of a river where it meets the sea. It creates a unique environment because both freshwater and saltwater are present. Tidal estuaries are characterized by narrow, shallow channels with a relatively constant width and depth. Tides are greatly amplified in these areas of smaller volume, which causes the tide to travel up the river.

WAVE ENERGYWave energy is produced when electricity generators are placed on the surface of the ocean. The energy provided is most often used in desalination plants, power plants and water pumps. Energy output is determined by wave height, wave speed, wavelength, and water density. To date there are only a handful of experimental wave generator plants in operation around the world.Wave energy is a renewable energy resource created by large storms hundreds of kilometres offshore that generate and transmit huge amounts of energy which travels great distances (via swell) and mixes with local influences (seas) to arrive at our shores. It is a genuinely renewable energy source and distinct from tidal energy.Wave energy is generally considered to be the most concentrated and least variable form of renewable energy. It is the high power density of wave energy that suggests it has the capacity to become the lowest cost renewable energy source.The World Energy Council has estimated that approximately 2 terawatts (2 million megawatts), about double current world electricity production, could be produced from the oceans via wave power. It is estimated that 1 million gigawatt hours of wave energy hits Australian shores annually and that 25% of the UK's current power usage could be supplied by harvesting its wave resource.

HYDROELECTRIC POWERHydroelectricity is the term referring to electricity generated by hydropower; the production of electrical power through the use of the gravitational force of falling or flowing water. It is the most widely used form of renewable energy, accounting for 16 percent of global electricity generation – 3,427 terawatt-hours of electricity production in 2010,[1] and is expected to increase about 3.1% each year for the next 25 years.Hydropower is produced in 150 countries, with the Asia-Pacific region generating 32 percent of global hydropower in 2010. China is the largest hydroelectricity producer, with 721 terawatt-hours of production in 2010, representing around 17 percent of domestic electricity use. There are now three hydroelectricity plants larger than 10 GW: the Three Gorges Dam in China, Itaipu Dam across the Brazil/Paraguay border, and Guri Dam in Venezuela.[1]

The cost of hydroelectricity is relatively low, making it a competitive source of renewable electricity. The average cost of electricity from a hydro plant larger than 10 megawatts is 3 to 5 U.S. cents per kilowatt-hour.[1] However, damming interrupts the flow of rivers and can harm local ecosystems, and building large dams and reservoirs often involves displacing people and wildlife.[1] Once a hydroelectric complex is constructed, the project produces no direct waste, and has a considerably lower output level of the greenhouse gas carbon dioxide (CO2) than fossil fuel powered energy plants.

NAME: DIPTY AGARWALCLASS: 10SECTION: BROLL NUMBER:11REGISTRATION NUMBER: B114084140067SUBJECT: SOCIAL SCIENCE

ECONOMICS

SUSTAINABILITY OF GROUND WATER.

SUSTAINABILITY OF GROUND WATER.

INTRODUCTIONGroundwaterThe importance of groundwater for the existence of human society cannot be overemphasized. Groundwater is the major source of drinking water in both urban and rural India. Besides, it is an important source of water for the agricultural and the industrial sector. Water utilization projections for 2000 put the groundwater usage at about 50%. Being an important and integral part of the hydrological cycle, its availability depends on the rainfall and recharge conditions. Till recently it had been considered a dependable source of uncontaminated water.

The demand for water has increased over the years and this has led to water scarcity in many parts of the world. The situation is aggravated by the problem of water pollution or contamination. India is heading towards a freshwater crisis mainly due to improper management of water resources and environmental degradation, which has lead to a lack of access to safe water supply to millions of people. This freshwater crisis is already evident in many parts of India, varying in scale and intensity depending mainly on the time of the year

The National Water Policy (1987) states that water is a prime natural resource, basic human need, and precious national asset. It gives special attention to drinking water for both humans and animals over its other uses. The policy calls for controls on the exploitation of groundwater through regulation and an integrated and coordinated development of surface- and ground-water. The central government has identified strategies for meeting drinking water needs and micro-watershed management and conducted pilot projects in different regions in the country. Even so, India is facing a freshwater crisis.

•Groundwater crisis is not the result of natural factors; it has been caused by human actions. During the past two decades, the water level in several parts of the country has been falling rapidly due to an increase in extraction.

•The number of wells drilled for irrigation of both food and cash crops have rapidly and indiscriminately increased.

•India's rapidly rising population and changing lifestyles has also increased the domestic need for water. The water requirement for the industry also shows an overall increase.

•Intense competition among users — agriculture, industry, and domestic sectors — is driving the groundwater table lower.

NAME: DIPTY AGARWALCLASS: 10SECTION: BROLL NUMBER:11REGISTRATION NUMBER: B114084140067SUBJECT: SOCIAL SCIENCE

GEOGRAPHY

CONSERVATION OF WATER

WHAT IS WATER CONSERVATION?

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.

AIMS OF CONSERVATION

- Revive traditional structures as well as create new infrastructure for water conservation- Increase the groundwater recharge in the watershed area- Increase water use efficiency in agriculture and domestic sectors by ensuring the adoption of water management techniques- Conserve fertile soil through soil and moisture conservation

RAINWATER HARVESTINGIn urban areas, the construction of houses, footpaths and roads has left little exposed earth for water to soak in. In parts of the rural areas of India, floodwater quickly flows to the rivers, which then dry up soon after the rains stop. If this water can be held back, it can seep into the ground and recharge the groundwater supply.

This has become a very popular method of conserving water especially in the urban areas. Rainwater harvesting essentially means collecting rainwater on the roofs of building and storing it underground for later use. Not only does this recharging arrest groundwater depletion, it also raises the declining water table and can help augment water supply. Rainwater harvesting and artificial recharging are becoming very important issues. It is essential to stop the decline in groundwater levels, arrest sea-water ingress, i.e. prevent sea-water from moving landward, and conserve surface water run-off during the rainy season.

WATER CONSERVATIONThe most important step in the direction of finding solutions to issues of water and environmental conservation is to change people's attitudes and habits¾this includes each one of us. Conserve water because it is the right thing to do. We can follow some of the simple things that have been listed below and contribute to water conservation.•Try to do one thing each day that will result in saving water. Don't worry if the savings are minimal¾every drop counts! You can make a difference.•Remember to use only the amount you actually need. •Form a group of water-conscious people and encourage your friends and neighbours to be part of this group. Promote water conservation in community newsletters and on bulletin boards. Encourage your friends, neighbours and co-workers to also contribute. •Encourage your family to keep looking for new ways to conserve water in and around your home.

NAME-DIPTY AGARWALCLASS- X BROLL.NO-11REG.NO-B114084140067PROJECT-SOCIAL SCIENCE

POLITICAL DEVELOPMENT

NARMADA BACHAO MOVEMENT

NARMADA BACHAO MOVEMENTNarmada Bachao Andolan (NBA) is a social movement consisting of adivasis, farmers , environmentalists,and human rights activists against a number of large dams being built across the Narmada river. The river flows through the states of Gujarat, and Madhya Pradesh in India. Sardar Sarovar Dam in Gujarat is one of the biggest dams on the river and was one of the first focal points of the movement. Friends of River Narmada is the unofficial website of the NBA.

CAMPAIGNS..Their mode of campaign includes hunger strikes and garnering support from film and art personalities(notably Bollywood actor Amir Khan). Narmada Bachao Andolan, with its leading spokespersons Medha Patkar and Baba Amte, received the Right Livelihood Award in 1991. History of the dam project post-1947,investigations were carried out to evaluate mechanisms for using water from the Narmada River, which flows into the Arabian Sea after passing through the states of Madhya Pradesh and Gujarat. Due to inter-state difference in implementing schemes and sharing of water,the Narmada Water Disputes Tribunal was constituted by the Government of India on 6 October 1969 to adjudicate over the disputes.

REASONS FOR THE ANDOLANIn 1985, after hearing about the Sardar Sarovar Dam, Medha Patkar and her colleagues visited project site and noticed that the project work being shelved due to an order by the Ministry of Environment and Forests, Government of India.The reasons for this was citedas “non-fulfillment of basic environmental conditions and lack of completion of crucial studies and plans.”What she noticed was thata the people who were going to be affected given no information but for the offer of rehabilitation. Due to this, the villagers had many questions from why their permission was not taken to whether a good assessment on ensuring destruction was taken. The World Bank, the financing agency for this project, came into the picture, Patkar approached the Ministry of Environment to seek clarifications. She realized, after seeking answers from the ministry, that the project was not sanctioned ata ll and wondered as to how funds were even sanctioned by the World Bank. After several studies, they realized that the officials had overlooked the post-project problems.

NARMADA BACHAO ANDOLAN