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Lecture – 06Environmental Impacts of Development: Impacts on waterGood morning. Welcome to the second week of the course on Sustainable Architectureand I am your instructor Doctor Avlokita Agarwal; Assistant Professor at Department ofArchitecture and Planning, IIT Roorkee. In the week one, we have seen the historicaldevelopment of sustainability as an idea, as a philosophy. We have seen the historicalevents which have led to the understanding of sustainability as it is today. We havetalked about the different visionaries of their times who in some way or the other haveworked towards enhancing or strengthening the idea of sustainability or sustainabledevelopment through the course of their works.We have also seen different definitions of sustainability and sustainable development asthey are being discussed in today’s times and how they have evolved. In this week, wewill be talking about the different problems of development, urban development orhuman made development and how it is impacting the natural environment. From thislecture onwards we will see the impacts of development on natural environment throughdifferent elements.Natural environment is primarily consisted of five basic elements; water, air, earth, spaceand fire or energy. Water being one of the most important element of naturalenvironment is also available in limited portions, limited proportion on our planet earth.It is one of the very basic life lines and earth is habitable only because it has water on it.It has water which we can drink and life can flourish.However, the development which humans have made have impacted the water bodies,the water sources on earth in a severely negative manner. Let us look at some of theimpacts on water. (Refer Slide Time: 03:02)One of the major impacts on water as an element is the shrinking of water bodies acrossthe world.(Refer Slide Time: 03:11)There are several areas like this one in California which have been converted to barrenlands or deserts; every subsequent year because of lack of rain, lack of precipitation.Now, this lack of precipitation itself is because of many reasons. It is because of the lackof forest cover, plants which help in bringing rains, which help in creating the humidityrequired for the rains precipitation to happen. Or it may also be because of the way development has taken around these areas which has blocked the streams, the channelsof water which are reaching a certain area certain land.But such sites are very common across the world where huge areas of land are graduallyconverted into barren land or gradually becoming desertified deserts.(Refer Slide Time: 04:17)This is another picture of Rye Path Dam in the year 2014 where there was no water inthe dam reservoir for the dam to operate for supplying downstream. And such was thecase in many many other water bodies in other parts of the world.(Refer Slide Time: 04:45) This particular image was taken from the October issue of National GeographicMagazine in 2014 which shows boats crowding a marina in a large reservoir lakeOroville north of Sacramento in California. That particular year was a severely draughtyear in US; especially in California and water bodies had reduced greatly shrinked insize.(Refer Slide Time: 05:12)This is a view of Shasta lake in California when it was full yet; not full, but it was 65percent below the historic average.(Refer Slide Time: 05:28) Again, the picture has been taken from National Geographic Magazine; this is an imageof Sun City in Phoenix, Arizona where it uses a 336 mile long336-mile-long system ofcanals and pipelines to carry water from the Colorado River through the desert.To only feed this city, the City of Phoenix; Sun City in Phoenix which houses hugepopulation, large population which further consumes a lot of water which is beingbrought to the city from a large distance.(Refer Slide Time: 06:09)This particular picture is of Enterprise Bridge which spans the Lake Oroville in ButteCounty California and this picture was in July 2011. (Refer Slide Time: 06:23)And, this one is the same place in 2014. Look at the devastation to the water body whichhas been caused. This is not the current state though it has gradually increased, the waterlevel has increased and 2014 was particularly a very bad year for the rains.But the condition is gradually deteriorating. This was a sudden change that is why it wasevident, it was visible; but such changes are happening worldwide across the world.(Refer Slide Time: 07:02)This is again Lake Oroville as in July 2011 where it is full to it is brim, people areenjoying. So, it is not just that water is essential for our survival as a basic need; for drinking and bathing and all other basic uses. But it is also an important means ofrecreation for us rejuvenating ourselves. This is the view of the same place in 2014where there is hardly any water left in Lake Oroville.(Refer Slide Time: 07:34)(Refer Slide Time: 07:38)This is the image of Folsom Dam in 2011 and in 2014. We can see huge areas beinginundated initially in 2011. (Refer Slide Time: 07:58)And they are gradually revealed towards the 2014 when the water levels have shrunk,declined. This particular image is of Aral Sea which is an inland sea. In from 1985 to2009, the sea a water body as large as a sea; it is called an Aral Sea was totally parcheddried up and it is now available in very small parts as lakes, small lakes.So, an area which is as large as this has been reduced to these small patches of waterbodies. All courtesy the human development which has taken place around it, theblockages to the water channels which were initially feeding this Aral Sea which werecoming from all these different sides, different channels. And, they have gradually beenblocked up. They have been blocked up. So, the water is actually not reaching Aral Seaand besides the drying up of this water body, it has subsequent impacts. People who werethriving because of the fishing industry, because of fishing in this sea Aral Sea; theyhave all lost occupation. People who were cultivating, who were using the water of thesea and the farmland which was around this sea is no more there. People are not farmingthere anymore because there is no water.The quality of land has totally changed from Greenland to a totally dried up desert likesituation is there. (Refer Slide Time: 09:50)This is how water bodies are shrinking. This is just one of the examples. There areseveral such examples, if you go to Bangalore; the famous Vrindavan gardens and thedam on Krishna River. An entire temple and an entire community was submergedbecause of making up of this dam which again revealed itself, because there were norains and there was no water in the reservoir.So, much so that an ancient temple got revealed again, which has been taken out andrebuilt on the banks of the reservoir, such examples are ample. They are available inplenty and what is that leading us to. It is leading us to a crisis of portable water; waterwhich is fit for drinking and human use. There is less and less of rainfall across the worldand hence our water bodies are shrinking. Cities which were once built on the banks ofrivers, no more can draw water from these rivers and that is something which is a causeof worry for governments across the world.And as water bodies shrink, it is not just the quality of life which deteriorates. It alsocreates socio political problems. Wars will be fought on water in the coming timesbecause that becomes a commodity. There will be countries, nations fighting over aresource as precious as water. Because rivers are uncontrolled, and people will fight togain the control of these water bodies if this shrinking of water body continues at thesame pace. Patrick Geddes; when he advocated for a regional plan, it implied taking careof all the elements together in a plan in planning. However, till today we have not been able to do that as he advocated. That is why such adevastating state, devastated state of water bodies, the availability of water across theworld. The second impact on water has been through pollution of water bodies. Thesewater bodies are of two types; one underground aquifer and surface aquifer, surfacewater bodies and pollution has reached both of them underground as well as surfaceaquifer. Now the pollution to these water bodies could be ofa further two types. It couldbe a point source pollution which is originating from one point or it could be a non pointsource pollution which is almost everywhere, either ways the water body iscontaminated. And it is not only unfit for portable use or human use, but it also stopssupporting the ecosystem. The other life forms; aquatic life, marine life and all other lifeforms which thrive through the water body because humans still consume a smaller partof, smaller portion of this water.There are several causes to this water pollution, how these aquifers are getting polluted,contaminated. One of the major causes of this is sewage. Almost everywhere across theworld traditionally we have dumped our sewage into water bodies, into flowing riverseventually converting them to drains, large drains. Huge rivers as large as Yamuna whichis originating from Glacier which is a perennial river which will not dry up, has beenconverted to look like a drain and that is one of the biggest rivers I am talking about.Smaller rivers have totally disappeared. We do not know whether there was a river at onepoint of time.You go to any city; Gwalior for example, has a huge nala, huge drain which is passingthrough the city which was at one point of time; a river named as Swubarnarekha. Peopledo not even know if a river ever existed. The city was actually on the bank of a river andsuch is the case with almost all water bodies because they have been totallycontaminated. And the reason is; our growing population, we are more in number asRamchandra Guha puts it and we are creating more and more of waste. Instead ofdisposing it properly, instead of treating it, we have taken to a very simple mechanism ofjust throwing our sewage waste into rivers. (Refer Slide Time: 15:14)Another cause a very serious of nature is dumping of industrial waste into water bodies.This industrial waste contains chemicals and heavy metals and these chemicals andheavy metals totally poison or disrupt the aquatic life. They poison they the; they poisonthe aquatic life. They enter they taken up by fish, the fish further enters our food chain. Itis part of the food chain and humans are poisoned by the; these chemicals and heavymetals which have already entered the system through pollution of water. There areseveral such examples and events instances of this pollution entering into the humanfood chain and affecting human life from across the world; for example, this event of1938 where a Japanese factory discharged a significant amount of mercury intoMinamata Bay.And which contaminated the fish stock there. And it does not get highlighted, it does notcome to the limelight immediately because the impact the effects are so subtle that ittakes decades, years to come to the forefront and get recognized. So, it is it gotrecognized much later and by that time it had already done the damage to the human lifeform. (Refer Slide Time: 16:58)This is one of a very distressing pictures where all the fish suddenly died, and an entirewater body was rendered dead. Because all the life form suddenly died because of thecontamination which was dumped into it through the industrial waste and such have beencases plenty of them.(Refer Slide Time: 17:30)Another cause is alien invaders. Now alien invaders in itself is not a cause, it is the resultof an activity like dumping of chemicals or excessive use of chemicals which have thengot washed off and entered into a water body. And then an alien invader enters into that aquatic system. Now what is alien invader; alien invader is actually an animal or a plantfrom one region which has introduced itself into another region.Now in this new region which is for example, a polluted water body which is getting alot of excessive fertilizer being washed into it ;it; because excessive fertilizer is beingused in the farmlands today. Now there is a lot of nutrition which is available for thisnew animal or plant species. Now this plant species or animal species will start to growstronger because it can thrive on the nutrition additional nutrition which is beingsupplied. And in that process, the population of this one specie grows beyond the limitwhile it did not even belong to that ecosystem. And thereby eating up on all other partiesto that ecosystem, all other life forms; plants or animals and thereby creating animbalance in the system.(Refer Slide Time: 19:02)And so, gradually none of the other life forms would survive, but only this life formwhich also may in the end totally eradicate get extinct from that water body; forexample, this water hyacinth. You must have seen this kind of image in several of thewater bodies. Now water hyacinth is an alien invader. It is not native. Why is it there inthis water body? Because there is a lot of nutrition available, because the sewer is beingdumped.Now, sewer is rich sewage is rich in nutrients and water hyacinth takes up all thatnutrition. It grows many fold, it multiplies very fast and it covers the surface of this entire water body. Because of covering of this entire water body, because of waterhyacinth the growth of water hyacinth. The water beneath, the water body is devoid ofsunlight and it also takes up all the oxygen. It is getting a lot of oxygen from theenvironment and it takes up all the BOD and there is no sunlight which is penetrated in.So, all the life form which is beneath in this water body will stop getting the nutrition,the sunlight, the oxygen which initially it was getting. And the water body eventuallyterms is turned dead; there is no life in it.Gradually the water hyacinth when the nutrition which it requires is not there, it will alsobecome dead and the entire water body is then dead.(Refer Slide Time: 20:57)Another major cause is dumping of plastic. (Refer Slide Time: 20:58)We are seeing distressing images like this. Lot of aquatic life like this turtle are dyingbecause of the plastic which is flooding our oceans and other water bodies. They aredying, they are getting paralyzed, they are their bodies are getting mutilated simplybecause we are dumping plastic. And some way or the other this plastic whendisintegrates enter into the bodies of this these aquatic life forms comes back into thehuman food chain.And we are also getting affected because of it.(Refer Slide Time: 21:41) Another major cause, speciallyespecially in India is religious ceremonies. We have thisfaith in immersing our idols into the water. Earlier, originally the way these idols werecreated; they were created out of unburnt clay and only organic colors which wouldderivedderive from nature were used on these idols. Now gradually as the times changed,more and more idols were required for celebrating these religious ceremonies, becausewe are more number of people. Now families or artists who were creating these idols,took a lot of time in creating these idols; because unburnt clay takes a lot of time to dryup and also the natural color takes a lot of time in its processing, making.So, to replace that labor intensivelabor-intensive process, people started using materials,alternative materials. So, instead of unburnt raw clay, they started using plaster of Paris.They started mixing gypsum, cement with the clay or sometimes making an entire idolout of plaster of Paris. And instead of making natural colors, they started using syntheticpaints, which are chemical based on to these idols. And it was very fast, because POPwould set within half an hour, and it would with the help of a cast.One family which was earlier able to produce only 5 to 10 idols in a season was able tomake 100 or 200 idols in a season; thereby increasing its his profit, the profit of thefamily, earning of the family, but in turn totally contaminating or polluting the waterbody. So, it is a change in culture which has led to the pollution contamination of thewater body.(Refer Slide Time: 24:05) Another major cause across the world is oil spills. Because of our lifestyle changinglifestyle, we need more and more of fuel oil for our day to day running of life. These oilsare procured out of some or the other oil field which leak and there are spills somewhereor the other in the world.It is not only affects the other life forms, but is it also affects people in those areas. Thereare cases where communities are fighting for their rights because their fields have beeninundated by oils, the spilled oil. Their cultivation, their primary occupation has beenruined. People are struggling for their own life because there are a lot of new diseaseswhich they have been exposed to and in turn the economy has gone down. So, initiallycommunities who were getting benefited economically out of setting up of an oil field intheir communities, gradually have their economy totally devastated; not able to survivebecause of a nexus, because of this whole chain of events.So, oil spill has been another major cause of water pollution.(Refer Slide Time: 25:47)Another cause though relatively smaller in proportion, but it is impact is often muchlarger and at times goes unnoticed for years and decades before its it comes to surface isdumping of radioactive waste. There have been cases where industries have dumpedtheir radioactive waste in water bodies and which has then created significant amount ofeffect negative impact on human life and all the aquatic life downstream. (Refer Slide Time: 26:31)Another cause is washing away of nutrients, excessive nutrients which are being used inour farmlands these days. This excessive washing away of nutrients causes alien invadersto enter into the system and then eat up all the oxygen of the water body and turn it into ahypoxic system. These are some of the images where algae as an alien invader, not analien invader it belonged to the system, but it increased it swelled in such proportionsthat that it renders the entire water body hypoxic. And the water body eventuallybecomes a dead zone.(Refer Slide Time: 27:22) If we look at the world, there are many- many dead zones across the world right now.And if these causes or solution to solutions to these causes are not found out, there willbe greater damage to the water bodies, water systems of the world. And it would be verydifficult for the human kind mankind to survive. The third impact is of altering watercycle. Besides shrinking water bodies and polluted water bodies, there is an impact onthe water cycle itself. All these three are connected to each other. In fact, everything thatis the fundamental of sustainability that everything in the world is connected to eachother.If we do something here, it has an impact on rest of the world though it may not beevident immediately. So, the water cycle is altered. When water cycle is altered becauseof one of the human activities, it has an impact on the size of the water bodies and waterbodies shrink. Once they shrink, they have a lesser capacity to carry the pollution, thecontamination, the waste and they become easily become polluted. So, all these three areinterrelated. Let us see how the water cycle is being altered.(Refer Slide Time: 28:56)But before we understand how water cycle, or any other cycle is being altered we have tofollow a systematic approach.The first of it is accounting; we have to first know where things are, how much of thatparticular component is stored in the ecosystem in which place. Once we have knownthat, as on date it is in current state of time current moment then we go on to see cycling. How things are moving from one state to the other state and how this entire cycle isgoing on. And simultaneously; we also talk about, we also understand the controls whichdetermine how the system is functioning and what are the factors that are driving thatcycling.So, now let us look at how all these three steps would be taken care of or understood interms of water cycle and then we will see how water cycle is altering here.(Refer Slide Time: 30:07)So, first of all it is accounting. If you look at 100 percent of the total water which isavailable on earth, only 2.5 percent of the water is available in surface aquifers andunderground waters. Rest of it 97.5 percent is in oceans which cannot be used by humansfor consumption. Out of that 2.5 percent, a large portion is logged in ice caps and iceglaciers.They gradually melt and become available to us in the form of water bodies. A large partof that 2.5 percent is also available as groundwater underground and only 0.014 percentis available in terms of surface water bodies, lakes, rivers and also the soil moisture ofthe topsoil. Now if we look if effeactively, we just have around 20 percent of 2.5 percentof water which is portable available to us for consumption. Now this is accounting; weknow we are talking when we are talking of contamination, we are talking of this justminute minuscule portion of this entire water body water which is present. We are contaminating groundwater as well as we are contaminating groundwater as well as thelakes and the rivers, the other water bodies.And it is hardly 1 percent of this total water which is available.(Refer Slide Time: 32:03)Now, how is the cycling happening? All of us have seen this water cycle right from ourschool classes. So, we know how water which is stored in surface aquifers say oceansand lakes and rivers gets evaporated. This evaporation is then transferred and then itprecipitates to come back to the land as well as water body as portable water. Part of itthis water actually percolates down the earth ground, part of it is also taken up by plantswhich further add to the evaporation through transpiration. This ground water isavailable in terms of soil moisture; part of it takes form of rivers and surface waterbodies and as part of this groundwater goes back to the oceans. This is how largelycycling is happening.Now, once we have understood how a cycle what a cycle is taking place if it is notaltered, this is what it is. However, if we look at it in current scenario; when we cut downthese treestrees, we have less of transpiration here. Less of transpiration implies let usless of precipitation here ;here; that is one. Second, the water which is available asgroundwater because we require more of it is then brought out to the surface. Now this isreducing. So, this groundwater is actually going down. We are consuming more and more of it and that is now the waste water is now being dumped into surface waterbodies even oceans.So, the quality of water though the overall quantity may remain the same, following thebasic scientific principle of the mass of anything remaining constant at any given pointof time. Though the quality of this water is going down, it is reducing. So, we have lessof portable water available in surface aquifers, we have less of groundwater available insurf underground water, we have less of precipitation which is further leading to severalother problems which is interconnected. We have less of vegetation, less of precipitationsupports lesser vegetation and vice versa.So, we have totally altered this water cycle and there is the final impact is that we haveless and less of portable water available. While at the same time, the water which getscapped as glaciers here and which reaches rivers and then oceans, this overall quantity isgoing up. Now this is non portable water. So, we have potable water quantity gettingreduced and we have non portable water quantity which is increasing further causingleading to a lot of problems. Now how will it be driven. So, we have to look at thecontrols. So, we have to see how the cycle is getting altered through the controls; firstand foremostforemost, of which is human consumption.(Refer Slide Time: 35:44)The human consumption if we look at historic data from 1950s to 1980s has increased atalmost four times across the world and specially in developed countries like US. Our traditional values especially in India where water was abundantly available; we havemany- many rivers and surface aquifers which were available for us, and our practices ofconservation of water have gradually given the way to a more wasteful practice ofconsuming water. And that is why more and more of portable water is being consumed,used up and also the groundwater which is portable water and hence the groundwatertable is going down. In several places it has gone down to double the depth of what itinitially used to be. So, the areas are becoming parched, they are becoming deserts.(Refer Slide Time: 36:54)The second control is temperature. Because of human activity, the global temperature isincreasing. We have more and more of greenhouse gases being emitted into theatmosphere because we are consuming the fuels, we are burning the fuels. Our lifestyleis more dependent on energy, different forms of energy. Conventional fuels like coal anddiesel, petrol, kerosene and also electricity even when it is coming from a lot ofrenewable energy sources, but our lives are becoming more and more dependent onthem. Now all this together and also a wasteful lifestyle ;lifestyle; all this is leading toglobal warming, rise in temperatures. Now this rise in temperature is melting theglaciers.Now, water; portable water which is stored in the form of ice caps and glaciers is meltingand it is reaching the sea. So, this melting of glaciers is causing sea level rise. It is alsocausing the rivers to flow at an increased pace at some point of the time in the year and at other times the flow is greatly reduced. So, there is no prediction or there is no continuityof the flow. So, certain areas are suddenly flooded because of this overflowing river andsometimes the areas which are otherwise fed by these rivers are forced to face draughtsthey are pushed.(Refer Slide Time: 38:44)Because of this increasing temperature, this is the state currently; the glaciers aremelting. As the climate change report has also pointed out.Kilometers and kilometers of glaciers have become water bodies, or they have becomethe flat lands. (Refer Slide Time: 39:04)And it is not just one, but almost all the glaciers. Very recently, I think last year mystudents from sustainable architecture went on for a trek trip to one of the glaciers inUttarakhand. And the glacier had shifted, drifted back 14 kilometers from what itinitially was almost three decades back. So, in three decades the glacier had drifted back14 kilometers. Now 14 kilometers and it is like thousand square kilometer of area whichwas initially a glacier has totally disappeared.Now, it is not feeding the rivers anymore, it is not available for people as portable water.That is the state almost everywhere. (Refer Slide Time: 40:05)(Refer Slide Time: 40:12)We can talk about any glacier and scientists are now recording how and at what pace theglaciers are receding, they are going back. (Refer Slide Time: 40:16)Now, all these melting glaciers are resulting in the rising sea levels. The water because itis constant the overall quantities constant, is now shifting from the ice caps and glaciersto these sea levels. And several nations are under the threat of getting submerged becausethe water is increasing like an entire nation of Mauritius.(Refer Slide Time: 40:48)This is the state and if another one meterone-meter sea level increases, several coastalareas across the world will totally be submerged.