Dr Johnson V, International Journal of Research in Engineering, IT and Social Sciences,ISSN 2250-0588, Impact Factor

Dr Johnson V, International Journal of Research in Engineering, IT and Social Sciences,ISSN 2250-0588, Impact Factor: 6.452, Volume 08 Issue 05, May 2018, Page 51-57 The Impact of Dams: A Study with Special Reference to the Dams on the Western Ghats of Idukki District, Kerala

Dr Johnson V (Associate Professor, Research and PG Department of Commerce, Pavanatma College Murickassery, Idukki, Kerala, India) Abstract: Dams are large socio-economic investments intended to facilitate domestic and industrial water supply, energy production, irrigation and flood control. Water resources projects such as dams represent large- scale engineering works or activities that can cause significant impacts on socio-economic components of the environment. The socio-economic benefits of dams are numerous and in many places dams have undoubtedly contributed to economic development. The economic benefits of dams have been assumed to outweigh the costs, thus providing rationale for construction of dams around the world. However, the development of these structures can be accompanied by negative biophysical, socio-economic, and geopolitical impacts; often through the loss of ecosystem services provided by fully functioning aquatic systems. The impacts of dams can be involuntarily imposed on marginalized peoples whose livelihoods are dependent on riverine resources. Moreoverdams are more likely to transform rivers and landscapes and create risks of irreversible impact. The paper attempts to analyse whether these impacts thatprevail elsewhere is true in the case of dams in the Western Ghats of Idukki districts in Kerala. Keywords: Dams, Flood Control, Impact, Ecosystem, Livelihood, Riverine Resources, Western Ghats.

I. INTRODUCTION Environmental and ecological studies have gathered phenomenal momentum recently, with the increased awareness about the importance of protecting nature for the future of mankind. Having had the age old distinction of being one of the spectacular landscapes on earth, the Western Ghats occupies a strategic position in the Indian ecological system. Human migration, which mainly began in the 19th century to these areas and the associated developmental activities of varied types undertaken thereafter, have a deleterious impact on the Western Ghats, resulting in its disfigurement and deterioration, of which the role of dams arefelt more devastating. Being the water tower of the Indian peninsula, the Western Ghats gives birth to rivers and lakes which are criss-crossed by about 169 dams and cascaded by a number of hydro electric projects, having disastrous impact on the environment .This paper, seeks to examine with special focus on the role of dams in the Ghats of Idukki district and tries to hypothesise that dams, being an offshoot of migration, play a more dreadful role than that of the role of the migrated people in damaging the environment, inflicting more institutionalised and planned assault on nature. The ecological importance of Western Ghats The Western Ghats are a mountain range that runs almost parallel to the western coast of Indian Peninsula. It is made up of a practically unbroken hill chain or escarpment running roughly in a north- south direction, for about 1500 km parallel to the Arabian sea coast, from the river Tapti down to Kanyakumari at the tip of the Indian peninsula; a hill chain that is extremely rich in biodiversity and crucial for the security of water resources of Peninsular India1. The area is one of the world's ten "Hottest biodiversity hotspots" and has over 5000 species of flowering plants, 139 mammal species, 508 bird species, 179 amphibian species and 288 freshwater fish species; it is likely that many undiscovered species live in the Western Ghats. At least 325 globally threatened species occur in this terrain. UNESCO, in 2006 decorated Western Ghats with the coveted World Heritage Status and there are 39 heritage sites at present including national parks, wildlife sanctuaries and reserve forests. The mountainous escarpment is solely responsible for the annual monsoon showers which keep alive the water sheds of the region perennial. These hills cover 160,000 sq km(62,000 sq mi) and form the catchment area for complex riverine drainage systems that drain almost 40 percent of India. The Ghats give birth to about 264 rivers which serve as a perennial source of water not only for the riverine people and animals but for about two fifth of Indian population. On these rivers about 169 dams were constructed over the centuries. Even in a narrow strip of land like Kerala there are 35 dams of which 10 dams in Idukki distict, including the phenomenal Idukki Arch Dam.Rivers, watersheds and aquatic echo systems are the biological engines on the planet. They are the life and http://indusedu.org Page 51

This work is licensed under a Creative Commons Attribution 4.0 International License Dr Johnson V, International Journal of Research in Engineering, IT and Social Sciences,ISSN 2250-0588, Impact Factor: 6.452, Volume 08 Issue 05, May 2018, Page 51-57 livelihoods of local communities. Understanding restoring and protecting eco systems at river basin level is essential to foster equitable human development and welfare of all species. Migration to western Ghats-Idukki –Major land marks  1700s-Tamilians known as the Muthuvans migrated to Munnar.  1877 Advent of European Planters. In 1877 Kerala Varma, the Raja of Poonjar, sold 227 sq. miles of Kannan Devan Hills to John Daniel Munroe, a British planter.  1890-1920 migration of plantation workers  1920-50- Mass migration of farmers to different parts of Idukki- Aftermath of II World War  1950 Colonies were established for Ex-servicemen Dams are an offshoot of institutionalised agenda. Dams were mainly made to meet the needs of the state and Tea companies. The Pall vassal Hydro-electric Project, the first Hydro-electric Project of the State was constructed by the Tea Companies for their industrial use. Before Migration, there were no Dams-the aborigines did not make any dams nor did the migrating peasants. Importance of the study Dams are large socio-economic investments intended to fulfil such purposes as domestic and industrial water supply, energy production, irrigation and flood control. Canter2 notes that water resources projects such as dams represent large-scale engineering works or activities that can cause significant impacts on socio-economic components of the environment. The socio-economic benefits of dams are numerous and in many places dams have undoubtedly contributed to economic development. The economic benefits of dams have been assumed to outweigh the costs, thus providing rationale for construction of dams around the world. However, the development of these structures can be accompanied by negative biophysical, socio-economic, and geopolitical impacts; often through the loss of ecosystem services provided by fully functioning aquatic systems. The impacts of dams can be involuntarily imposed on marginalized peoples whose livelihoods are dependent on riverine resources. Moreover dams are more likely to transform rivers and landscapes and create risks of irreversible impact. This common phenomenon prevails elsewhere istrue in the case of dams in the Western Ghats of Idukki districts in Kerala as well. Dams in the Western Ghats are an offshoot institutionalised and planned assault on nature. Almost all dams in the Western Ghats particularly in Idukki District are an after math of the migration which started in the 19th century by Europeans to Munnar and nearby areas. In Kerala there are 35 dams of which 10 dams are in Idukki distict ,including the phenomenal Idukki Arch Dam .These dams cover an area of 177 Sq km.The Idukki Dam ,the biggest on the western Ghats covers an area of 59.2 sq km.Therefore the paper attempts to examine the impacts of dam projects in the light of their positives and negatives, taking into account the environmental and livelihood impacts of dams in this region.

II. OBJECTIVES AND METHODOLOGY 1. 1To gain a general understanding about the Western Ghats 2. 2To study Dams in general 3. 3To identify the Major dams on the Western Ghats 4. 4To analyse the varied impacts of dams on the region The study is descriptive and analytical. Secondary data have been collected for the purpose of the study. The information is collected from various sources such as books, journals, published articles and internet. Dams-An Overview Rivers have played a major role in shaping the earth’s physical and ecological landscapes through their unique hydrologic characteristics, as well as shaping cultural landscapes by providing food, water, and other ecosystem services. With the rise of ancient civilizations came a rise in building dams and diversions for water storage, irrigation, transportation, and flood control. As early as 6500 BC, the Sumerians constructed dams across the Tigris and Euphrates rivers to provide flood control and irrigation for crops 3.By the first millennium BC, stone and earthen dams were erected on nearly every continent, enabling the acquisition of water and food to sustain population growth. Today, more than 800,000 dams have been constructed worldwide, of which 45,000 are large dams, greater than 15 m in height, 4. Around 400,000 sq km of land worldwide has been submerged due to the construction of dams. The rapid increase in dam projects during the early and middle twentieth century was driven by socio- economic and political pressure, political-ecology dimension of developing countries (Goodland 1997) and advances in structural engineering, such as the use of pre-stressed concrete 5, also contribute to the proliferation of dams. Latest statistics show that there are more than 5000dams in India covering a submerged area of about 8400 sq km. The Ghats give birth to about 264 rivers which serve as a perennial source of water not only for the riverine people and animals but for about two fifth of Indian population. On these rivers about 169 dams were constructed over the centuries. Even in a narrow strip of land like Kerala there are 35 dams of which 10 dams in http://indusedu.org Page 52

Idukki distict, including the phenomenal Idukki Arch Dam .The dams cover an area of 177 sq km. The Idukki Dam, the biggest on the Western Ghats covers an area of 59.2 sq km The idea of making a dam in Idukki was proposed by Shri Kolumban of Araya race in 1922.The Malankara Estate superintendent AC Thomas Edattu showed interest in the project, which is the starting point of making Idukki dam. Then later in 1932 Shri W.J.John of Malankara estate made report on the Idukki dam project to Government of Travancore .In 1947. Sri P.D Joseph John the electrical engineer made a preliminary report on the dam project .Then in 1956 Central water commission made a detailed survey .The dam project is sanctioned in 1961 and in 1963 the project started. In 1973 the reservoir commenced. The trial run is made in October 4 in 1973. Honourable prime minister of India Smt. Indira Gandhi inaugurated the commercial distribution of electricity on 12th February in 1976.The M/S S.N.C Inc. Of Canada assisted the whole project. The other Major dams in Western Ghats of Idukki are Ponmudi, Anayirangal, Kundala, Mattuppetti, Sengulam, Lower Periyar and Mullapperiar. Meaning of dams A dam is a barrier constructed to hold back water and raise its level, forming a reservoir used to generate electricity or as water supply. It is an impervious barrier constructed across a river or stream to store water on its upstream side. Dams are built for meeting different purposes such as irrigation, power generation, flood control, navigation, recreation, fisheries and aquatics etc. Classifications of Dams Gravity Dam It is a masonry or concrete dam which resists the forces acting on it by its own weight Arch Dam It is a curved masonry or concrete dam, convex upstream, which resists the forces acting on it by arch action. The only arch dam in India – Idukki dam (double curvature in plan) – concrete arch dam Buttress Dam It consists of water retaining sloping membrane or deck on the u/s which is supported by a series of buttresses. These buttresses are in the form of equally spaced triangular masonry or reinforced concrete walls or counter forts. The sloping membrane is usually a reinforced concrete slab. In general, the structural behaviour of a buttress dam is similar to that of a gravity dam. Embankment Dam It is a non-rigid dam which resists the forces acting on it by its shear strength and to some extent also by its own weight (gravity). Its structural behaviour is in many ways different from that of a gravity dam. The impacts of dams on the biological, geophysical, and chemical processes of rivers have been extensively documented 6.Although specific environmental impacts of dams are influenced by local conditions, as well as the size and type of dam constructed, similar environmental impacts of dams have been documented in various regions of the world, and are generally not unique to a specific location or ecosystem. Negative environmental impacts of dams can occur upstream, downstream, and in reservoirs. In addition to habitat degradation or destruction, dams induce significant barrier effects by block king the downstream flow of sediment and nutrients and prevent ing the migration of fish and other aquatic organisms.7 Additionally, altered flow rates may negatively impact aquatic organisms that depend on critical thresholds of water level, velocity, or timing for life history stages8. Dams may also negatively impact aquatic organisms by altering water temperature and dissolved oxygen both within reservoirs and outflows. (Lessard and Hayes 2003). Reservoirs may also contribute to atmospheric greenhouse gases through the decomposition of flooded biomass and soils9. Submergence of valleys and low lying sites which are often of exceptional geological, ecological, cultural and therefore touristic (economic) value. Thórhallsdóttir 10 points out that most of the biodiversity of the highlands occurs in the river valleys and low lying wetlands, making these areas particularly valuable in Icelandic context. These aspects are sought to be addressed in the foregoing discussions. Physical Impacts of Dams Physical impacts are composed of construction, mitigation and decommissioning costs.  Construction Costs: Project construction consists of the dam, the irrigation system and the spillway. Huge commitment of funds for a relatively long time is required in this connection, the benefits of which are uncertain in terms of time and cost .This may be further aggravated by time and cost overruns during construction, pausing severe financial crunch in the form interest payment etc, an Achilles heel in the context of India. The Edmalayar Dam in Kerala on the WG is a typical example. The Dam project, started in 1970, could be commissioned only in 1987 with a time overrun of 9 years and consequent cost overrun of 285 percent resulting in a capital cost of Rs 2.81 per kWh of generation.11  Mitigation Costs: Dams change river flow. This affects the livelihood of people who live in the reservoir area and even downstream users. Examples of mitigation measures include the building of fish ladders to enable fish to go upstream to lay eggs, or planting trees in other areas to replace trees cut down to make way for the dam, requiring huge capital investment. Though this is quite common in all http://indusedu.org Page 53

cases, in Kerala, particularly in Idukki District this issue does not seem to have addressed with due importance. There are no fish ladders or adequate planting of trees to mitigate the losses, suffered.  Repair and maintenance cost: To keep the dam useful for a long time, repairs have to be carried out on a sustained basis. This requires capital expenditure like huge cash outflow over the life time of dams.  Decommissioning: This impact will occur at the end of the life of a project when the dam is no longer useful. It refers to the removing of the dam and restoring the river to its pre-dam state. This is necessary for safety and environmental reasons. Most dams do not last their predicted lifetime and many considerably less 12. Inappropriate removal will however, create negative impacts on downstream aquatic life due to the sudden flush of sediments accumulated in the dam reservoir. Decommissioning of dams can cost almost as much as building them, involving complex dredging, drainage and reconditioning of the reservoir and is never included in cost benefit analysis. Many American dams are now being decommissioned after only 50-70 years of energy production13. In Idukkithe Mullaperiar Dam is facing an imminent threat of decommissioning  Resettlement of the Population Displaced by Dams: Dam construction can have severe and widespread effects displacing whole communities from construction and inundation areas and disrupting patterns of communication, social and economic systems as well as land-holding and resource use. An estimated 40 to 80 million people have been displaced by dams worldwide. The Aswan High Dam on the Nile displaced a greater number of people, 120 000 Nubians, both in Egypt and Sudan14.Yet mitigation, compensation, and resettlement attempts are often inadequate. Land leased for construction also has to be accounted for as a project resettlement cost. In any event, the affected people are eligible for compensation and rehabilitation15cited this issue in connection with the rehabilitation problem for the settlement of the Ramanagar for refugees of the Kali Hydroelectric project. This observation was later proved correct in the case of other Dams on the Western Ghats. For instance people displaced from Idukki dam project area got settled in different part of kerala. It has to be noted that resettlement issues have multi-pronged impact VIZ, economic, social, cultural and ecological, the actual cost might be many times more than expected.  Risk of Loss due to Dam Failure: There is a possibility that a dam might fail. Dam failure means the collapse or movement of part of a dam or its foundation, so that the dam cannot retain water16. The general causes of dam failure are overtopping, internal erosion in the body and in the foundation of the dam. Sometimes insufficient spillway capacities induce the failure as well. Moreover, large dams may actually increase the risk of earthquakes. This would also increase the risk of catastrophic dam failure at the site. This risk has to be accounted for as a negative impact of the project in terms of human and material loss. The effect of dam failure can be catastrophic. St. Francis dam, USA failed in 1928 caused by foundation failure, Killing 450 people. Morbi dam failure was a dam-related flood disaster which occurred on August 11, 1979 in India, killingabout 25000 people. InIdukki district of Kerala one of the oldest dams, viz, Mullapperiyar Dam, constructed in 1885, is under the imminent threat of Dam failure .Though Tamil Nadu continues to reject this possibility, many scientists including Madhav Gadgil(WGEEP2001) is of the conviction that Dams completed 50 years of life span should be decommissioned before any catastrophe arises.  Land Acquisition costs for the loss of forest: The land acquisition impact is the loss of forest, agricultural and residential lands. Since the loss of agricultural land and residential areas is accounted for under resettlement costs, the cost of land acquisition focuses on forests. The government need not pay anything to obtain the right to use national forests because these are considered public property. There is however, an economic opportunity cost in that if a dam were not constructed, the forest could be used for other purposes. This opportunity cost has to be accounted for. Deforestation results in the loss of both direct and indirect uses of the forest. The latter include ecosystem and biodiversity conservation and carbon sequestration. Direct uses stem from forests being a source of timber, non- timber forest products, and wildlife. All these can be sold as commercial goods or consumed by local households. The loss of forest uses is accounted for as external costs, which is seemed to have been neglected in the case of dam projects in Kerala, as the area nearby lay abandoned and the submerged areas were not adequately compensated by fresh planting of trees.  Externalities: An externality is defined as a cost or a benefit resulting from some activity or transaction that is imposed or bestowed upon parties outside the activity or transaction. One possible externality of a dam project is the release of greenhouse gas from the decomposition of organic matter in reservoirs. This will have an adverse effect on global climates. Methane gas and CO2 production from rotting vegetation and soil, and processes at the dam head (known as the fizzy drinks effect), can be up to 54 times that of equivalent gas powered plants in tropical reservoirs. (Methane has 28-34 times http://indusedu.org Page 54

more atmospheric warming potential than CO2). As reservoirs rise and fall, vegetation continues to grow and rot on fertile silty soil and on the reservoir surface, leading to continued emissions throughout the dams lifetime. Similiarly water logging and salinity can have an adverse impact on agricultural production by the rise of groundwater brought about by surface water. When water tables are close to the surface, capillary action draws salts naturally occurring in the soil profile to the surface. Salinisation will reduce yields of crops that do not tolerate high salinity levels. Socio-Economic Impacts of Dams The socio Economic Impact of Dams vary in importance and magnitude depending upon the geophysical conditions, demographic variations and method of construction of dams and so on, with the following impacts emerging there from. Inundation of Settled Areas and Destruction of Natural Habitats The growing worldwide environmental awareness has increased attention on the impacts of dams on communities (Canter, 1985). Church (1968) states that few of humans’ modifications of the landscape can initiate such profound physical, economic and social changes as dams. This suggests the need for a better understanding of the socio-economic impacts of dam construction. Dams raise the natural level of rivers, so flooding lands previously settled, farmed or periodically grazed. Dam construction results in the loss of productive land beneath the reservoir. The largest reservoirs in Africa include the Volta Lake formed behind the Akosombo Dam, which covers 8 500 square kilometres, flooding a substantial area of Central Ghana (Canter, 1985). Dams also result in the destruction of natural habitats. According to Canter (1985) the shift from river to Lake Environment can result in the reduction of species diversity. Dams may lead to the loss of rare flora and fauna species. Impoundments lead to decreased woodland thereby adversely affecting wildlife communities. This leads to decreased hunting and associated uses. Medicinal herbs will also be lost. Furthermore, decreased forest plant communities lead to decreased timber production and attractiveness of an area to recreationists. For instance the Idukki Arch dam submerged a forest area of about 59.20 square km, while Mullapperiar Dam submerged an area of 23 sq.km. Spread of Diseases Large dam projects often lead to the spread of schistosomiasis and other communicable diseases like yellow fever, malaria, and river blindness and liver fluke infections. Newson 18notes that devastating water- borne diseases are introduced by reservoirs and their associated irrigation works. Furthermore, Newson argues that dams have reduced the quality of drinking water for hundreds of millions of people. Clarke19states that when large new volumes of water are created, the risk of disease in tropical countries rises sharply. Adams (1992) argues that although water-borne diseases are widespread in African floodplains, dam construction can increase their prevalence. Improved access to clean water is a major benefit of dams. But the habitat they create is perfect for disease-carrying mosquitoes and snails, which bring illnesses such as malaria and schistosomiasis. Social disruption and higher population densities in resettled communities can result in poor hygiene and a host of related diseases. Since most of the dams in this region are away from human settlements, the issue of spread of diseases have not been so seriously felt so far in the Ghats of Idukki. Loss of Sites of Historical, Archaeological and Religious Importance Damage to cultural heritage sites River valleys are important sources of African history. The construction of dams results in the loss of African historical, archaeological, cultural and religious sites. These sites are relevant in Africa, where local indigenous people were seen as inferior and culturally static by the European colonizers. African post-independence governments are also playing an active role in attempting to discover more about the cultural history of the indigenous peoples as a way promoting nationhood20.In many places, large dams have impacted cultural heritage by the submergence and destruction of cultural resources such as shrines, buildings, artefacts, burial sites, and sacred landscapes. This situation remained in alarming proportion while most of the dams were constructed in Idukki as many historic sites were submerged including Ayyappan Kovil(a famous temple) in Idukki. More over the advent of alien species of funa and flora brought by worker etc has really upset the ecological balance. Building of roads in connection with dam construction has made it easier for poachers, quarry mafia and so forth to step in so as to disfigure nature and wild animals. Pollution Dam construction can lead to noise and visual pollution. Noise is generated at the impoundment construction site during the construction phase Noise can be defined as objectionable or unwanted sound. Complaints of noise nuisance generally arise when a noise interferes with work, communication, recreation or sleep. Damming can also adversely affect the visual quality of an area. Furthermore, it can result in the water resource producing a bad odour. This reduces the attractiveness of the area to recreationists. Preservationists argue that free-flowing rivers should be left intact in order to avoid spoiling the beauty of the landscape21. Social and Cultural Disruption Canter (1985) notes that during the dam construction phase there can be social conflict between the local villagers and some dam construction workers that maybe foreign. Foreign construction workers may http://indusedu.org Page 55

This work is licensed under a Creative Commons Attribution 4.0 International License Dr Johnson V, International Journal of Research in Engineering, IT and Social Sciences,ISSN 2250-0588, Impact Factor: 6.452, Volume 08 Issue 05, May 2018, Page 51-57 disregard and disrespect local culture and authority. People displaced by dam construction maybe moved to land claimed by others. Friction can occur, arising from the resentment felt by the original owners of the land towards the newcomers who have been foisted on them. The resettled people may also be angry over having had to leave their old lands (Brokensha & Scudder, 1968).This situation remains true in the case of people displaced by dam construction in the Western Ghats of Idukki as well in particular when the construction of Idukki Dam Project was on: there was an exodus of people to different places. Earthquakes Reservoir-Induced Seismicity (RIS)can occur by the weight of the reservoir on nearby fault lines, and lubrication of faults by excess water. There are many recorded cases of this effect, including 5 strong earthquakes on the Indian peninsula in the 1980´s and 4 earthquakes over 6 Richter since the 1960´s. Even small earthquakes (common under dams) can lead to dam cracking and reservoir overtopping, as in the Vaiont dam disaster in Italy which killed 2,600 people when landslides caused the dam to overflow (McCully, 2001). Earthquakes can be induced by dams. Globally, there are over 100 identified cases of earthquakes that scientists believe were triggered by reservoirs. The most serious case may be the 7.9-magnitude Sichuan earthquake in May 2008, which killed an estimated 80,000 people and has been linked to the construction of the Zipingpu Dam,in china. Though no major causalities have been reported so far most of the dams in Idukki are hit byseismic threats of varied magnitudes. Moreover many of these dams lie in earthquake proned areas. Effects downstream of the dam Dams create an impassable block in the river system which seriously reduce the amount, and alter the nature, of downstream flow. Effects of this aspect include: Sediment deprivation of nutrient rich organic silt to farmland, freshwater fish populations, and eventually to the sea, as silt and sediment are trapped behind the dam. This leads to less fertile farmland along floodplains of the river, erosion of the riverbed and bank, and a decrease in riverine fish. When the river meets the sea sediment deprivation causes serious erosion of coasts and deltas and enormous damage to fish and algal populations which require calcium from the sediment for nutrition. The subsequent decrease in algae reduces drawdown of atmospheric carbon (which algae normally consume), and has a considerable effect on climate change on a global scale (60% of the worlds large rivers are dammed) 22. Fish populations and other biodiversity are seriously affected by dams. Salmon and other migrating fish cannot pass the dam to reach their spawning grounds. Dams impose disruption of natural ecosystems, particularly of floodplains, threatening the livelihoods of the millions of people downstream of dams who depend on fisheries, wetlands, and regular deposits of sediment for agriculture. This is true with the downstream of Periyar River on which Idukki Dam is constructed, and with most other rivers in Idukki.

III. CONCLUSION Rivers, watersheds and aquatic echo systems are the biological engines on the planet. However, dams in Idukki have cut the livewire of nature-the rivers. They are the life and livelihoods of local communities. “Dams are institutionised, planned and organised assault” on nature. They have done more harms in the western Ghats through deforestation, quarrying, mining, construction, obliteration of landscapes and river systems etc, than the migrating peasants, heavily outweighing the benefits. Neither the aborigines nor the migrated peasant community can be held responsible for the so called disfigurement of the Western Ghats. It is horrifying that we have to fight our own government to save the environment-Ansel Adams, American environmentalist. Hence the need of the hour to keep the dead rivers alive so that they become water rich. Therefore it is strongly recommended that, as a preliminary step, water from the reservoirs in Idukki be released in a systematic manner so that the flow in the river can be restored to a certain extent and gradually the river may be brought back to its pre-dam stage.

IV. REFERENCES [1] Western Ghats Ecology Expert Panelreport, Aug 2011,. Madhav Gadgil Report [2] Canter, 1985, L, Environmental Impact of Water Resources Projects, Michigan: Lewis Publishers,. [3] McCully,Patrick, 2001, Silenced Rivers: The ecology and politics of large dams,London, Zen Books. [4] DiFrancesco, K. and Woodruff, K.,.2007, Global perspectives on large dams: report on a conferenceheld November 3 –5, 2006.New Haven, CT: Yale School of Forestry and Environmental StudiesPublication Series, [5] 5. Arthur, H.G1977,and Nambe Falls Dam: first mechanically prestressed concrete dam in United States. Civil Engineering, 47 (11), 50–53, [6] Goldsmith, E. and Hildyard, N.1984. The social and environmental effects of large dams. San Francisco, CA: Sierra Club Books, [7] Lessard, J.A.L. and Hayes, D.B.,. Effects of elevated water temperature on ﬁsh and macro invertebrate communities below small dams. River Research and Applications, 9 (7), 721–732, 2003 [8] Bunn, S.E. and Arthington, A.H.2002, Basic principles and ecological consequences of altered ﬂow regimes for aquatic biodiversity. Environmental Management, 30 (4), 492–507 [9] St. Louis, V.L., et al.,2000. Reservoir surfaces as sources of greenhouse gases to the Atmosphere: a global estimate. Bio- science, 50 (9), 766–775. http://indusedu.org Page 56

[10] Thórhallsdóttir2007.,( Thóra Ellen, in press. ‘Environment and energy in Iceland: a comparative analysis of values and impacts.’ Environmental Impact Assessment Review-Report of working group 1. Govt of Iceland. [11] "Time and Cost Over-Runs Of The Power Projects In Kerala" (PDF). cds.edu. pp. 7, 26, 27, 29. Retrieved 30 January 2011). [12] Besant-Jones,. 1993.‘The future role of Hydropower.’ in Hunt, R, and Hunt J.M. ‘How does Hydropower compare?’. Independent Energy.Nov, 1993. p.14, [13] Skalar, L.. ‘The dams are coming down’.World Rivers Review. First quarter, [14] Adams, W.M.(1992),. Wasting the rain: Rivers, people and planning in Africa. London: Earth scan Publications [15] Madhav Gadgil 1979.-Hills, dams and forests some observation from the western ghats, Indian Academy of sciences vol2,part3 [16] International Commission on Large Dams, ICOLD,(1995). [17] Fearnside, P.M.1995. ‘Hydroelectric dams in the Brazilian Amazon as sources of Greenhouse Gases’.Environmental Conservation. Vol.22, No.1, [18] Newson, M. Land,(1997). Water and development: Sustainable Management of river basin systems. London: Frank Cass and Company, [19] Clarke, R,(1991)Water: The International Crisis. London: Earth scan Publications Limited, [20] Brokensha, D. & Scudder, T..,(1968) Resettlement. In N. Rubin & W.M. Warren (Eds.), Dams in Africa: An Inter- disciplinary Study of Man-made Lakes in Africa. (pp. 20-62). London: Frank Cass and Company Limited [21] Henwood, K. & Coop, C.(1973).Impact analysis and the planning process. In C.R. Goldman, J. McEvoy & P.J. Richerson (Eds.), Environmental Quality Water Development. pp. 170-182). San Fransisco: W.H. Freeman and Company, [22] Gislason, Sigurdur R. et al,., 2006. ‘Role of river-suspended material in the global carbon cycle’. Geology.

http://indusedu.org Page 57

This work is licensed under a Creative Commons Attribution 4.0 International License