Categories
Water

Sterilization of Water

Introduction
Water is the major constituent of all living beings. The water is necessary to sustain all types of life. The water used for drinking purpose by human beings should full the following conditions :
1. It should be colourless.

2. It should not possess any smell.
3. It should contain any harmful dissolved salts such as nitrates, mercury salts, lead salts.
4. It should not contain any living organisms such as algae, fungus, bacteria, etc.
Sterilization of Disinfection of Water
In order to obtain water for drinking purpose, water is first treated with alum whereby clay and other colloidal particles go precipitated the suspended impurities are then removed by filtration, and the clear water obtained is subjected to some suitable treatment to destroy harmful germs and bacteria. These bacteria cause many dangerous diseases such as cholera, thyroid, dysentery, tuberculosis, diphtheria, etc.
The process of killing the harmful bacteria by some suitable treatment of water is called sterilization of the disinfection of water. The common sterilizer agents are chlorine, ozone, bleaching powder, potassium per magnate chloramines. Sterilization of water through bleaching powder gives chlorine and if it is in excess, it is harmful to health and causes diseases like chlorosis, unconsciousness, etc. So here we determine the exact amount of bleaching powder used of required for the sterilization of given samples of water.
General Methods of Sterilizing Water
There are many methods of sterilizing water but the best is one which gives a sample of water which is totally free from germs. Sometimes potassium per magnate is used to disinfect water but it is not for drinking as it gives red colour and the excess of it is in harmful for health. We use dissolve in water, so it can not be used in large scale. Another method for disinfection is by simply boiling the water for about 15 minutes, but this powder. The chemical action of bleaching powder on germs and bacteria is due to the chlorine which becomes available when it is added to water.
So here in the present context, we shall focus on disinfection of water using bleaching powder.
Theory
Objective: Our objective of this project is to determine the amount of bleaching powder required for the sterilization of given samples of water. So certain steps are taken in the context as follows :

A known mass of the given samples of bleaching powder is dissolved in water to prepare a solution of known concentration. This solution contains dissolved chlorine, liberated by the action of bleaching powder with water. CaOCl2 + H2O ——————-> Ca(OH)2 + Cl2
The amount of chlorine present in the above solution is determined by treating a known volume of the above solution with an excess of 10% potassium iodide solution when the equivalent amount of iodine is liberated. The iodine, thus liberated is then estimated by titrating it against a standard solution of sodium thiosulphate using starch solution as indicator. Cl2 + 2KI ——————–> 2KCl + I2 I2 + 2Na2S2O3 ——————> Na2S4O6 + 2NaI
A known volume of one of the given samples of water is treated with a known volume of bleaching powder solution. The amount of residual chlorine is determined by adding excess potassium iodine solution and then titrating against standard sodium thiosulphate solution.
From the reading in 2 and 3, the amount of chlorine and hence bleaching powder required for the disinfection of a given volume of the given sample of water can be calculated.

Requirements for the Experimental Determination
Requirements are as follows :
Apparatus :

Burette
Titration Flask
500 ml measuring flask
100 ml Graduated Cylinder
250 ml Measuring flask
1lt. Measuring flask
Glazed Tile
Glass Wool.

Chemicals :

Bleaching powder -5gm.
Na2SO4—->12. 4 gm.
KI – 25gm.
Different Sample of Water
Distilled Water
Soluble starch – 1gm.
Indicator – Starch Solution.

Procedure :

Preparation of N/20 Na2SO4 solution: Take 12. 4 gm of sodium thiosulphate hydrated and mix it in about 500ml of water then the mixture is diluted to make the volume 1000ml. or 1lt. Normality = strength/Molecular Mass. = 12. 4 / 248 = 1/20N
Preparation of 10%KI solution: Take 25gm. of KI powder and mix it in about 100ml of water then dilute the mixture to make the volume 250 ml and take it in the measuring flask.
Preparation of Bleaching Powder solution: Weight 5gm of bleaching powder and mix it in about 200 ml of distilled water in a conical flask. Stopper the flask and shake it vigorously. The suspension thus obtained is filtered through glass wool in measuring flask of 500ml. and dilute the filtrate with water to make the volume 500 ml. The solution of obtained is 1% bleaching powder of solution.
Preparation of starch solution: Take about 1gm of soluble starch and 10 ml of distilled water in a test table mix vigorously to obtain a paste. Pour the paste in about 100ml. of hot water contained in a beaker with constant stirring. Boil the contents for 4-5min. and then allow cooling.
Take 100ml. of distilled of water and then 20ml of bleaching powder of solution in a stopper conical flask and add it 20ml of 10% KI solution. Shake the mixture, titrate this solution against N/20 Na2S2O3 Solution taken in the burette. When a solution in the conical flask becomes light yellow in colour adds about 2ml of the starch solution as indicator. The solution now becomes blue in colour. The endpoint is the disappearance of blur colour, so continue titrating till the blue colour just disappears. Repeat the titration to get a set of three readings.
Take 100ml of water sample in a conical flask and add 20ml of KI solution and stopper the flask. Shake it and titrates against N/20 Na2S2O3 until the solution becomes yellow. Then add 2ml of starch solution and then again titrate till the blue colour disappears. Repeat titration for three readings.
Repeat step 6 with other samples of water and records the observation.

Observation Table
Titration: I

Volume of distilled water is taken 100ml
Volume of bleaching powder sol. taken 20ml
Volume of KI solution added 20ml

Burette Reading Sr. No.
Initial
Final
Final Vol. of 0. 2N Na2S2O3 sol. used

1.
1. ml
0. 9ml
7. 7ml

2.
0. 9ml
16. 6ml
7. 7ml

3.
16. 6ml
24. 0ml
7. 7ml

Titration: II

Volume of water sample I taken 100ml
Volume of bleaching powder sol. added 20ml
Volume of KI solution added 20ml

Burette Reading Sr. No.
Initial
Final
Final Vol. of 0. 2N Na2S2O3 sol. used

1.
10. 1 ml.
16. 2 ml.
6. 1 ml.

2.
16. 2 ml.
22. 3 ml.
6. 1 ml.

3.
22. 3 ml.
28. 4 ml.
6. 1 ml.

Titration: III

Volume of water sample I taken 100ml
Volume of bleaching powder sol. added 20ml
Volume of KI solution added 20ml

Burette Reading Sr. No.
Initial
Final
Final Vol. of 0. 2N Na2S2O3 sol. sed

1.
8. 9 ml.
14. 1 ml.
5. 2 ml.

2.
14. 1 ml.
19. 3 ml.
5. 2 ml.

3.
19. 3 ml.
14. 5 ml.
5. 2 ml.

Titration: IV

Volume of water sample I taken 100ml
Volume of bleaching powder sol. added 20ml
Volume of KI solution added 20ml

Burette Reading Sr. No.
Initial
Final
Final Vol. of 0. 2N Na2S2O3 sol. used

1.
16. 1 ml.
21. 6 ml.
5. 5 ml.

2.
21. 1 ml.
27. 1 ml.
5. 5 ml.

3.
27. 1 ml.
32. 6 ml.
5. 5 ml.

Calculations
Sample I  (TAP WATER) Amount of bleaching powder used to disinfect 100ml of water samples I. = (7. 7 – 6. 1) ml of 0. 2 N of Na2S2O3 solution. 1. 6ml. 1ml of bleaching powder solution contains bleaching powder =5/500 = 0. 01gm. 20ml of bleaching powder solution = 7. 7ml of 0. 2N of Na2SO4 So 1ml of Na2S2O3 solution = 20/7. 7 ml of bleaching powder solution. Volume of bleaching powder solution used to disinfect 100ml of water = 1. 6 x 20/7. 7ml. 1. 6 x 20/7. 7 ml. of bleaching powder solution =1. 6 x 20 x 0. 01 gm / 7. 7 = 0. 4156 gm
Sample II  (POND WATER) : Amount of bleaching powder used to disinfect 100ml of water. = (7. 7 – 5. 2) ml of 0. 2 N Na2S2O3 solution = 2. 5ml 1ml of bleaching powder solution contains bleaching powder = 0. 1 gm. 7. 7ml. of 0. 2N Na2S2O3 = 20ml of bleaching powder solution So 1ml of Na2S2O3 = 20ml. of bleaching powder solution. Volume of CaoCl2 solution required to disinfect 100ml of water. = 2. 5 x 20/7. 7 ml. 2. 5 x 20/7. 7 ml. of bleaching powder solution. = 2. 5 x 20 x 0. 01 gm / 7. 7 of bleaching powder
Amount of bleaching powder required to disinfect 1 let. of water. = 2. 5 x 20 x 0. 01 x 1000 / 7. 7 x 100 = 25 x 2/7. 7 = 0. 6493 gm.
Sample III (TANK WATER) : Amount of bleaching powder used to disinfect 100ml of water. = (7. 7 – 5. 5 ) = 2. 2ml of 0. 2 N of Na2S2O3 solutions. ml of bleaching powder solution contains bleaching powder. = 5/500 = 0. 01gm 7. 7 ml. of 0. 2 N Na2S2O3 = 20ml of bleaching powder solution.
so 1ml of 0. 2 N Na2S2O3 solution = 20/7. 7 ml volume of bleaching powder solution used to disinfect 100ml of water = 2. 2 x 20/7. 7 ml. 2. 2 x 20/7. 7 ml of bleaching powder solution = 2. 2 x 20 x 0. 01 gm / 7. 7 of bleaching powder
Amount of bleaching powder used to disinfect 1 ltr. of water = 2. 2 x 20 x 0. 01 x 1000 / 7. 7 x 100 = 22 x 2/77 = 0. 5714gm
Results
Amount of the given samples of bleaching powder required to disinfect one litre of water :
Samples I = 0. 4156
Samples II = 0. 6493
Samples III = 0. 5714
Thus we get the amount required for disinfection and if bleaching powder is taken less than this amount water will remain impure and if it’s taken in excess than this will also be harmful as it will contain chlorine. The results show that Samples II is the imputes water as the amount of bleaching powder requires is maximum and Sample I is less impure than others as the bleaching powder used is minimum. The tables also show the difference. Titration III has minimum reading because of impurities and titration I has maximum reading because the sample was distilled water.
Conclusion
This is a convenient method of sterilizing water. It leaves no impurities and its harmful effect if bleaching powder is taken in the right amount. In this way, we can calculate the amount of bleaching powder required for any sample of water and then take it in large amount if the water is to be disinfected on a large scale as in waterworks. And thus the only cause of using bleaching powder to disinfect water instead of any other method is this that it kills all germs and bacteria due to its chemical action and provides us with a pure sample of water to use for all-purpose.

Categories
Water

Laboratory Report – Recovery of Grip Strength Following Cold Water Immersion

Abstract
The research here has looked at the impact that cold water immersion has on the physical performance of athletes and the way in which this immersion can impact on fatigue. The results showed that cold water immersion has a direct impact on the level of fatigue with those that have used cold water immersion will show less fatigue and will perceive themselves to be using less energy in achieving the same grip.
Introduction

The purpose of this practical experiment is to look in more detail at the use of cold immersion as a means of dealing with a variety of problems such as pain and trauma. The aim of this research is to look at how cold immersion can be used as part of the treatment of athletes (Bell, et al 1987).
Issues associated with cold immersion have many potential applications both in terms of dealing with injuries, rehabilitation as well as encouraging recovery from exertion in a relatively quick manner. The background literature will be drawn upon in relation to this issue, in order to focus on the precise information that is expected to be gleaned from the chosen laboratory report. However, it is important to note, at this early stage, that the main aim of the experiment undertaken here is to focus is on looking at the recovery of grip strength when an individual has their hands immersed in cold water. The subjects involved were not those with injuries and therefore the primary focus is on the impact that cold water immersion has on the grip of an individual where there is no injury present; the principle, however, could potentially have a broader application in the context of recovery following exertion, or where there is an injury present (Halvorson, 1990).
Sports related injuries have increased, in recent years, as more people are participating in recreational sports as well as an increase in opportunities to enjoy sports on a more competitive basis. With this in mind, the possible treatment of injuries or indeed the prevention of injuries is of increasing concern, not only to those who participate in sporting activities, but also to the National Health Service itself which is allocating an increasing amount of resources to treating those with sporting injuries which could have potentially been prevented or at least treated more immediately, without the requirement for medical intervention.
The treatment of cold water immersion is therefore seen as particularly relevant to this discussion, as it is a self-help treatment which could be undertaken by any individual, without the need for medical intervention. Furthermore, where there are particular signs of success in using this treatment, it may be possible for injury to either be prevented, or the impact of these injuries diminished, to such an extent that savings are made within the Health Service.
The experiment here looked at whether or not there is an effect on muscle fatigue, as well as considering the subjective impression that the individuals had over their fatigue, with the individuals undertaking handgrip contractions with cold immersion happening in between effective exercises (Johnson et al 1990).
Not only is the actual physical level of the grip looked at as part of the experiment, but also the perceptions of the individuals, as this is also thought to be an important aspect of treating sports’ injuries. By looking at the perceptions that an individual has about their own strength and ability to maintain a strong handgrip, as well as measuring the physical level of strength they are displaying, any discrepancies can be identified. This, again, presents a potential argument that individuals who have been treated in a certain way will perceive themselves to be in a better place, or more able to undertake sporting activity, even when it may not necessarily be reflected in their physical status.
In order to gain the relevant information from the experiment being undertaken here, it is first necessary to look at previous literature in the area of cold water immersion, with reference to both recovery time and recovery from injury. Much of the previous research which has focussed on sports rehabilitation has considered the success of various different sports rehabilitation programmes in relation to one particular area of injury, such as tendonitis related injuries. Moreover, when focusing on the ability of an individual to recover from such a sports injury, the literature typically takes a broader view than simply looking at one technique such as cold water immersion. For example, in the paper undertaken by Levy et al., in 2009, the focus is placed on five areas that would be relevant to recovery from a sports injury, namely confidence, coping, social support, motivation and pain, indicating that an individual’s ability to recover from a sports injury or to fend off fatigue would depend as much on surrounding factors and emotional issues, as it does on physical treatment (Levy, et al 2009).
In this context and applying this to the current research, it would be expected that looking at the perceived level of exertion being displayed by the subjects would offer information as to whether or not the general emotional strength of the individual has a bearing on the level of fatigue experienced and the reaction to cold water treatment (Halvorson, 1990).
Distinctions have been found in previous literature in this area in relation to the way in which professional athletes or those with a particular affiliation with a sport will undergo a recovery period, in comparison to individuals who simply participate in sports activities, from a recreational perspective. This would suggest that those primarily involved in rehabilitation from a recreational point of view will be focused more on the reduction of pain, rather than from the standpoint of enhancing performance. Bearing this in mind, it could be argued that the reaction to cold water immersion may well vary, depending on the underlying goals of those involved. For example, a professional athlete may be more motivated to ensure consistently strong athletic performances and will therefore be less likely to experience fatigue, whereas those who are more recreational in their attitude may be less likely to push themselves in terms of the level of exertion that they display.
Methods
All specific procedures were followed according to the Coventry University laboratory manual. The experiment involved 20 maximal handgrip contractions with a rest period of 20 seconds between each exercise, followed by 2 minutes of the hand being submerged in water which was either 5° or 20° temperature; then a further 20 maximal hand grips were used. A 20 minute rest period was then had while another group would undertake their exercise, before completing the exercise all over again. Throughout this process, the force being generated with each contraction was recorded, in order to gain an understanding as to whether the immersion treatment would improve the situation, or not. All of this is done without physical intervention from the tester at any point. By undertaking twenty separate periods of exertion and taking the average of each individual participant, it will be possible to gain an understanding of general trends associated with cold water immersion and the impact that this type of treatment can have on the regular activities undertaken by the individuals. Using both water immersion at 5° and 20° will also enable a meaningful comparison between cold water immersion and warm water immersion. Indeed, it could potentially be argued that any form of treatment may have an impact on the perceptions of the individual patient. In this case, averages were taken in order to allow for a meaningful analysis to be completed; however, it may be necessary to look at any instances of individuals who show unusual results, so as not to have the effect of skewing the overall results. It is also noted that a different set of individuals needed to studied, in the context of the impact of immersion in both cold and warm water and again this may have an impact on the results. Although both sets of individuals were subjected to the same test conditions and were asked to perform the test, both prior to and after exertion, so that the differential could be compared in a meaningful manner, this may be particularly relevant when it comes to the rate of perceived exertion, as perceptions are clearly more of an individual factor that will vary from person to person.
RPE (Rating of Perceived Exertion) was also recorded to identify any difference between actual and perceived levels of fatigue). RPE was obtained for each individual, both before and after immersion in cold or warm water, depending on the individual being questioned. This was done as an overall figure, rather than after every individual immersion, as there were concerns that if the individual was asked several times about their perceived level of exertion, they would begin to answer without careful thought and simply respond based on their previous response, rather than as a meaningful assessment of the level of exertion displayed.

Results
The results of the experiments are discussed here with graphical and quantitative representation included in the appendix. A total of 16 individuals (in 2 groups of 8) were used as part of the experiment involving both warm and cold water, with the level of exertion recorded throughout. When looking at the average level of exertion across all 20 grips and eight individuals (in total 160 results), the average before being immersed in warm water was not significantly higher than the average after being immersed in warm water, with a difference of just 0 .12; interestingly, the perceived level of exertion actually increased by a not particularly substantial 0.6.
When looking at the level of force being displayed by the eight individuals who immersed their hands in warm water, prior to the immersion, it could be seen that there was a relatively wide variance even among the subjects themselves, with one person showing an average force of 23.5 and another showing an average force of 50.05. However, when looking, in more detail, at the individual 20 different tests taken by these individuals, there was a relatively high level of consistency across each of the 20 grip tests. For example, the subject who showed the low average of 23.5 displayed the highest force of 27 and the lowest of 20, showing that the average of 23.5 was in fact a fair reflection of their own grip, albeit substantially less powerful than the other subjects in the experiment.
In contrast, the position in relation to those who had immersed their hands in cold water showed an increase in the level of the average force which increased by 1.7. There was also a trend in the perceived level of exertion, indicating that those individuals who had been immersed in cold water and who had a higher level of force after the immersion did not actually perceive themselves to be working any harder a statement which is supported by the earlier research undertaken by Tomlin and Wenger in 2001. This suggests that the immersion in cold water showed more consistent results when it came to the perception of exertion being used, with the subjects on average showing no fatigue. Despite this, only one of the subjects stated that they found no difference in the level of exertion between before and after immersion, with all other subjects showing either a slight increase or a decrease. On average, however, when looking at all of the subjects, there was no difference in the overall level of perceived exertion.
As was the case with those subjected to warm water immersion, all subjects showed generally a higher level of force, with one of the individuals showing an average force of 48.1, prior to immersion, and another showing 24.55, prior to immersion. This indicates that there were substantial variations amongst the subjects and, as such, taking averages was perceived as being the most appropriate method when looking at the overall impact of immersion, without having to take account of individual strengths and weaknesses.
Discussion
The results produced during this laboratory experiment indicate that the use of cold water immersion can decrease the level of perceived effort, to such an extent that greater strength can then be displayed by individuals when completing a handgrip (Halvorson, 1990). This is despite the fact that the individuals undertaking the experiment did not perceive themselves to be using greater exertion, after their hands had been immersed in cold water. It also became readily apparent that immersion in cold water had an impact on the level of fatigue experienced and the ability of the subjects to recover from exertion. Despite the fact that the respondents said that they, on average, experienced no difference in the level of perceived exertion, there was a clear indication that they were able to display more force after immersion in cold water than they were beforehand which supports the findings of Sanders in 1996. Similar results were not shown in the case of warm water immersion and very little change was experienced in the actual level of exertion, and the perceived level of exertion actually increased. Applying this to the background literature and understanding, it could be seen that the main result ascertained from this laboratory experiment is that cold water immersion decreases the “normal” levels of fatigue and allows for quicker recovery, post exercise (Johnson et al 1979).
These results suggest that there is merit in the argument that the use of cold water immersion can improve athletic performance, as individuals are able to show greater strength and force, without increasing their level of perceived exertion. With this in mind, it is suggested that cold water immersion be explored, in greater detail, as a means of improving athletic performance. It is also suggested from these results that cold water immersion could have broader applications for the treatment of injury or pain, although the experiment here is focussed on the level of strength and impact on fatigue. Applying these findings, alongside the background understanding, allows this report to suggest that cold water immersion could be used as a means of treating sports injuries, or those suffering from muscle fatigue following sporting activity. As cold water immersion would ultimately allow an individual to recover from exertion at a quicker rate, it would then be possible to argue that the same physical benefits could be obtained during the use of the cold water immersion when dealing with the recovery from injury or, indeed, the prevention of injury, by reducing the level of fatigue experienced.
Conclusions
The laboratory experiment undertaken during this research looked specifically at the impact that water immersion has on an individual’s ability to grip forcefully, by looking at a set of individuals who immersed their hands in warm and in cold water. Through comparing the level of force that they were able to display, it was possible to ascertain whether or not any trends are emerging in terms of the level of fatigue experienced and how cold water immersion would have an impact on this.
It was found that those who had immersed their hands in cold water experienced less fatigue in their grip and, importantly, their own perception of exertion being exercised, thus indicating that it is not only the actual level of grip that increases, but also the fact that they perceived that their level of exertion had not changed during the test. It was concluded, therefore, that the use of cold water immersion can not only offer solutions for those experiencing fatigue, but also for those looking to increase the sustainability of athletic performance, over a longer period of time.
The results of this experiment also need to be considered in the context of the literature presented previously, which suggests that the level of recovery and reaction to fatigue may depend on the motivations of the individuals involved, with professional athletes being more likely to react positively to such activities.
References (other research looking at this issue is detailed below):
Bell, A.T., Horton, P.G., 1987. The uses and abuse of hydrotherapy in
athletics: a review. Athletic Training 22 (2), 115–119.
Byerly, P. N., Worrell, T., Gahimer, J., & Domholdt, E. (1994). Rehabilitation compliance in anathletic training environment. Journal of Athletic Training, 29, 352-355.
Halvorson, G.A., 1990. Therapeutic heat and cold for athletic injuries.
Physician and Sportsmedicine 18 (5), 87–92
Johnson, D.J., Moore, S., Moore, J., Olive, R.A., 1979. Effect of cold
submersion on intramuscular temperature of the gastrocnemius muscle.
Physical Therapy 59, 1238–1242
Levy, A., Polman, R, Nicholls, A and Marchant, D (2009) Sports Injury Rehabilitation Adherence: Perspectives of Recreational Athletes. ISSP 7: 212:229
Sanders, J. (1996). Effect of contrast-temperature immersion on recovery
from short-duration intense exercise, Unpublished thesis, Bachelor of
applied Science, University of Canberra
Tomlin, D.L., Wenger, H.A., 2001. The relationship between aerobic
?tness and recovery from high intensity intermittent exercise. Sports
Medicine 31 (1), 1–11

Categories
Water

Water Scarcity

Global Water Scarcity – Problems And Solutions Posted: 23. 12. 2009 author: Tater, Prof. Dr. Sohan Raj Importance of Water Water is a source of life of every living organism. Without water living beings cannot survive their lives. There is 60% water in human gross body. It is a natural resource that sustains our environments and supports livelihood. Water is the blue gold, and that future wars will be fought for water. So, not a single drop of water received from rain should be allowed to escape into the sea without being utilized for human benefit. The vast majority of the Earth’s water resources are salty water, with only 2. % being fresh water. Approximately 70% of fresh water available on planet is in the icecaps of Antarctica and Greenland leaving the remaining 0. 7% of total water resources worldwide available for consumption. However from this 0. 7%, roughly 87% is allocated to agricultural purposes. These statistics are particularly illustrative of the drastic problem of water scarcity facing humanity. Water scarcity is defined as per capital supplies less than 1700 M3/year. The comprehensive assessment of water management in agriculture revealed that one in three people are already facing water shortage (2007).
Around 1. 2 billion people, or almost one-fifth of the world’s population, live in areas of physical scarcity, while another 1. 6 billion people, or almost one quarter of the world’s population, face economic water shortage (where countries lack the necessary infrastructure to take water from rivers and aquifers); nearly all of which are in the developing countries. Agriculture is a significant cause of water scarcity in much of the world since crop production requires upto 70 times more water than is used in drinking and other domestic purposes.
The report says that a rule of thumb is that each calorie consumed as food requires about one litre of water to produce. The amount of water in the world is finite. The number of us is growing fast and our water use is growing even faster. A third of world’s population lives in water stressed countries now. By 2025, this is expected to rise to two-third. The UN recommends that people need a minimum of 50 litres of water a day for drinking, washing, cooking and sanitation. In 1990, over a billion people did not have even that. Causes of Global water Crisis

There are four main factors aggravating water scarcity: * Population Growth: In the last century, world population has tripled. It is expected to rise from the present 6. 5 billions to 8. 9 billions by 2050. Water use has been growing at more than twice the rate of population increase in the last century, and although there is no global water scarcity as such, an increasing number of regions are chronically short of water. * Increased urbanization will focus on the demand for water among an over more concentrated population. Asian citizen alone are expected to grow by 1 billion people in the next 20 years. High level of consumption: As the world becomes more developed, the amount of domestic water that each person used is expected to rise significantly. * Climate change will shrink the resources of fresh water  (a) Pollution and disease Global water consumption rose six fold between 1900 and 1995 more than double the rate of population growth – and goes on growing as farming, industry and domestic demand all increase. As important as quantity is quality – with pollution increasing in some areas, the amount of useable water declines.
More than five millions people die from water-borne diseases each year, 10 times the number killed in wars around the globe. Seventy percent of water used world wide is used for agriculture, much more will be needed if we are to feed world’s growing population – predicted to rise from about six billion to 8. 9 billion by 2050. Consumption will star further as more people expect western – style lifestyle and diets – one kilograms of grain fed beef needs at least 15 cubic meters of water, while a kilo of cereals needs only upto three cubic meters. b) Poverty and Water The poor are the ones who suffer most. Water shortage can mean long walks to fetch water, high price to buy it, food insecurity and disease from drinking dirty water. But the very thing needed to raise funds to tackle water problems in poor countries, economic development – requires yet more water to supply the agriculture and industries which drive it. The UN-backed World commission on water estimated in 2000 that an additional $100 billion a year would be needed to tackle water scarcity would wide.
Even if the money can be found, spending it wisely is a further challenge. Dams and other large – scale projects now affect 60% of the world’s largest rivers and provide millions with water. As ground water is exploited, water tables in part of China, India, West Asia, the former Soviet Union and the Western United States are dropping – in India by as much as 3 meters a year in 1999. (c) Melting of Glaciers Global warming is melting glaciers in every region of the world, putting millions of people at risk from floods, draughts and lack of drinking water.
Glaciers are ancient rivers of compressed snow that creep through the landscape, shaping the planet’s surface. They are the Earth’s largest fresh water reservoir, collectively covering an area the size of South Antarctica. Glaciers have been retreating worldwide since the end of the little Ice Age (around 1850), but in recent decades glaciers have began melting at rates that cannot be explained by historical trends. One in three people is enduring one form or other of water scarcity, according to a new report from the International Water Management Institute (IWMI).
The report says that about one- quarter of the world’s population lives in areas where water is physically scare, while about one – sixth of humanity over a billion people – live where water is economically scares, or places where “Water is available in rivers and aquifers, but the infrastructure is lacking to make thick water available to people. ” In a world of unprecented wealth, almost two million children die-each year for want of a glass of clean water and adequate sanitation.
Millions of women and young girls are forced to spend hours collecting and carrying water, restricting their opportunities and their choices. Water – bone infectious diseases are growing in same of the world’s poorest countries. Human development reports 2006 investigates the underlying causes and consequences of a crisis that leaves 1. 2 billion people without access to safe water and 2. 6 billion without access to sanitation. In 2006 the International Management Institute, reported that water scarcity affected a full third of world population.
In 2007 the Intergovernmental panel on climate change predicted that due to climate change, the number of people facing water scarcity would grow. Other, too, say that there is a global water crisis, the availability of water is dwindling, the world is running out of the water. Solution of water scarcity (a) Water and Climate change Water scarcity is expected to become an even more important problem than it is today. There are several reasons for this: * First the distribution of precipitation in space and time is very uneven, leading to tremendous temporal variability in water resources worldwide (Oki et al. 003). For example, the Atacama Desert in Chile receives imperceptible annual quantities of rainfall where as Mawsynram, Assam, India receives over 450 inches annually. If the fresh water on the planet were divided equally among the global population, there would be 5000 to 6000 M3 of water available for everyone, every year. * Second the rate of evaporation varies a great deal, depending on temperature and relative humidity, which impact the amount of water available to replenish ground water supplies.
The combination of shorter duration but more intense rainfall (meaning more run off and less infiltration) combined with increased evapotranspiration (the sum of evaporation and plant transpiration form the earth’s land surface to atmosphere) and increased irrigation is expected to lead to ground water depletion. According to world bank, as many as two billion people lack adequate sanitation facilities to protect them from water – borne disease, while a billion lack access to clean water altogether.
According to United States, which has declared 2005-15 the “Water for life” decade, 95 percent of the world cities still dump water sewage into their water supplies. Thus it should come as no surprise to know that 80 percent of all the health maladies in developing countries can be traced back to unsanitary water. Developed countries are not immune to fresh water problem either. Researcher found a six-fold increase in water use for only a two-fold increase in population size in the United States since 1900.
Such a trend reflects the connection between higher living standards and increased water usage and underscores the need for more sustainable management and use of water supplies even in more developed societies. (b) Technical Solution New technology can help, however, especially by cleaning up pollution and so making more water useable, and in agriculture, where water use can be made for more efficient, drought – resistant plants can also help. Drip irrigation drastically cuts the amount of water needed, low-pressure sprinklers are an improvement, and even building simple earth walls to trap rainfall is helpful.
Some countries are now treating wastewater so that it can be used – and drunk – several times over. Desalination makes seawater, but takes huge quantities of energy and leaves vast amount of brine. (c) Climate Change In any case, it is not just us who need water, but every other species that shares the planet with us – as well as the ecosystems on which we, and they, rely. Climate change will also have an impact, some areas will probably benefit from increase rainfall, but other are likely to be loser. We have to rethink how much water we really need if we are to learn how to share the Earth’s supply.
While dams and other large-scale schemes play a big role worldwide, there is also a growing recognition of the value of using the water already have more efficiently rather than harvesting ever more from our rivers and aquifers. For millions of people around the world, getting it right is a matter of life and death. (d) The hydrological Cycle The hydrological cycle begins with evaporation from the surface of ocean or land, continues as air carries the water vapour to locations where it forms clouds and eventually precipitates out.
It then continues when the precipitation is either absorbed into the ground or runs off to the ocean, ready to begin the cycle over again in an endless loop. The amount of time needed for ground water to recharge can vary with the amount of intensity of precipitation. With world population expected to pass nine billion by mid-century, solutions to water scarcity problems are not going to come easy. Some have suggested that technology – such as large-scale salt water desalination plants – could generate more water for the world use.
But environmentalists argue that depleting ocean water is no answer and will only create other big problems. In any case, research and development into improving desalination technologies is ongoing, especially in Saudi Arabia, Israel and Japan. Already an estimated 11,000 desalination plants exist in some 120 countries around the world. Water Management When we think about water scarcity, then, we should not be focusing on an absolute shortfall between the total needs of the earth’s population and the available supply, but on where the useable water is and what it costs to bring enough clean water to where people are.
Applying market principles to water would facilitate a more efficient distribution of supply everywhere. Analysts at Harvard Middle East Water Project, for example, advocate assigning a monetary value to fresh water, rather than considering it a free natural commodity. They say such a approach could help mitigate the political and security tensions caused by water scarcity. Falling prices in membrane filtering technology (reverse osmosis) and advances in ultraviolet and ozone disinfections have led to a wide array of off – the shelf water technologies.
Large companies such as GE, Siemens and Dow developed these technologies for consumer markets in industrial countries, spurred by the exploding market in bottled water, but they offer interesting spin-offs in developing countries. As individuals, we can also reign in our own water use to help conserve what is becoming an ever more precious resource. We can hold off on watering our lawns in times of drought. And when it does rain, we can gather gutter water in barrels to feed garden hoses and sprinklers. We can turn off the tapes while we brush our teeth or shave, and take shorter showers.
In other world, “Doing more with less is the first and easiest step along the path toward water scarcity. ” As a reliable and affordable technology, desalination has come of age in the last two decades. For Iceland cities such as Singapore, or for a new five star hotel on a Pacific atoll, a desalination plant is now standard technology. The cost of desalination has come down rapidly and now ranges from $ 0. 5 – 1. 00 per cubic meter, depending upon price of energy. This is a reasonable price for drinking water in a developed urban area or hotel where the impact on room prices will be only a few dollars per day.
For agricultural purposes, however the value of water ranges from several cents per cubic meter to grow crop such as corn, wheat, rice or sugar cane, to half a dollar for intensive flower or vegetable production. Desalination is clearly not an economical option. Desalination is similarly impractical for poor people who live on less than $ 1 or $ 2 per day. Conclusion Water is a source of life of every living organism. Without water living beings cannot survive their lives. There is 60% water in human gross body. It is a natural source that sustains our environments and supports livelihood.
Water is the blue gold, and that future wars will be fought for water. So, not a single drop of water received from rain should be allowed to escape into the sea without being utilized for human benefit. Present global water scarcity is defined as per capita supplies less than 1700 M3/year. Around 1. 2 billion people, or almost one-fifth of the world’s population, live in areas of physical scarcity while another 1. 6 billion, or almost one quarter of the world’s population, face economic, water shortage. A third of world’s population lives in water stressed countries now.
The report says that a rule of thumb is that each calorie consumed as food requires about one litre of water to produce. Causes of Global water crisis are – population growth, increased urbanization, high level of consumption and climate change which shrink the resources of fresh water, melting of glaciers. More than five millions people die from water-borne diseases each year around the Globe due to drinking polluted water. Underground water table is depleting on an average 3 meters a year as per research conducted in India. One in three people is enduring one form or other of water scarcity around the Globe.
Almost two million children die each year for want of a glass of clean water and adequate sanitation. If the fresh water on the planet were divided equally among the global population, there would be 5000 to 6000 M3 of water available for every one, every year. Technical solutions of water scarcity around Globe are Drip irrigation, recycling of sewage water and to make it usable for agriculture, vegetables and bathroom purposes, scientific work over hydrological cycle formation, desalination of saline water, Increasing R. O. technology.
We should advocate assigning a monetary value to fresh drinking water, rather than considering it a free natural commodity. Individually every globe citizen should save water in bathing cooking, gardening i. e. their daily use purposes. References * Goudie, As (2006). Global Warming and Fluvial Geomorphology Volume 79, September 2006, 37th Binghamton Geomorphology Symposium – The human role in changing Fluvial Systems. * Huntington, T. G. (2005) Evidence for Intensification of the global water cycle: Review and Synthesis. Journal of Hydrology, 319. * Konikow, Leonard et al. 2005). Ground water Depletion: A Global Problem. Hydrogeology (13). * Nearing, M. A. et al. (2005). Modeling Response of Soil Erosion and Run off to changes in Precipitation and cover. Catena, 61. * Oki, Taikan et al. (2006). Global hydrological Cycles and World Water Resources, Science; 313. * Vorasmarty, Charles et al. (2000). Global Water Resource: Vulnerability from Climate Change and Population Growth, Science, 289. * World Water Assessment Programme, 2003. Water for people, Water for life: The United Nations world water development report. UNESCO: Paris.

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Water

Rain Water Harvesting: A Solution To Water Crisis

Water is an essential resource. No one can live and survive without water. Hence, we should not let the source of the life waste, instead we must store it. We can do so by the methods of Rainwater Harvesting. Rainwater Harvesting refers to the process of collecting and storing of rainwater. Rainwater harvesting helps in providing drinking water, water for irrigation, agricultural purposes or for groundwater recharge. It is one of the best solutions to water problem in the areas having inadequate water resources. Rainwater systems are simple to construct.
Usually, rainwater is either harvested from the ground or from a roof. During the rainy seasons, the rain water can be collected and stored in the tanks. There are many methods to harvest the rainwater. Usually, the methods used are: Catchments Areas i. e. the areas which receive rainfall directly. In this, paved areas like roof of a building or unpaved area such as open ground or lawns can be used for the catchment areas. Ground catchment techniques has more chances of collecting water from the larger surface areas.
Storage system: It is designed according to the amount of water that is needed to be stored. Storage system must be sealed and does not leak. Chlorine must be put from time to time to keep the water clean. Conveyance systems which transfer the rainwater collected on the rooftops to the storage tanks and that is done by making connections to one or more down-pipes connected to the rooftop gutters or pipes. The gutters must be made as such that if it rain starts,the dirt will be washed into the down-pipe and clean water comes out. Advantages/Benefits of Rain water Harvesting:

It is one of the best solutions to water problem in the areas having inadequate water resources Reduction of soil Erosion. Improved quality of ground water. Raising of water level in wells and borewells. Reduction in the choking of storm water drains and flooding of the roads. Rain water flows down the hills in the form of small streams which join together to form rivers and lakes. And this is the important and the natural source of water for the living beings. Some of the rain water percolates down the earth until it reaches the hard surface.
There it collects to form a large underground water reservoir. Such water is obtained on digging wells and it is called sub-soil water or ground water. Thus, there are three important natural sources of water besides abundantly available sea water. The sea water being saline can not be sued as such either for industries or for domestic consumption. (a) Rain water or snow water. (b) Surface water (river, lakes, streams, canals, ponds, etc. ) (c) Ground water or sub-soil water wells and springs. Rainwater Harvesting
In urban areas, the construction of houses, footpaths and roads has left little exposed kuchha earth for water to soak in. In parts of the rural areas of India, flood water quickly flows to the rivers, which then dry up soon after the rains stop. If this water can be held back by storage or by reducing speed of flow, it can seep into the ground and recharge the ground water 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 ground water depletion, it also raises the declining water table and can help augment water supply. Rainwater harvesting and artificial recharging are becoming very important methods. It is essential to stop the decline in ground water levels, arrest sea-water ingress, i. e. , prevent sea-water from moving landward and conserve surface water run-off during the rainy season. Town planners and civic authority in many cities in India are introducing by-laws making rainwater harvesting compulsory in all new structures.
No water or sewage connection would be given, if a new building did not have provisions for rainwater harvesting. Such rules should also be implemented in all the other cities to ensure a rise in the groundwater level. Realizing the importance of recharging ground water, the CGWB (Central Ground Water Board) is taking steps to encourage it through rainwater harvesting in the capital and elsewhere. A number of Government buildings have been asked to adopt water harvesting in Delhi and other cities of India. All you need for a water harvesting system is rain, and a place to collect it.
Typically, rain is collected on rooftops and other surfaces, and the water is carried down to where it can be used immediately or stored. You can direct water run-off from this surface to plants, trees or lawns or even to the aquifer. Some of the benefits of rainwater harvesting are as follows: I. Increases water availability II. Checks the declining water table III. Is environmentally friendly IV. Imporves the quality of ground water through the dilution of fluoride, nitrate, and salinity V. Prevents soil erosion and flooding, especially in urban areas