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Monday, September 16, 2019

A Life Cycle Analysis Of A Dam Environmental Sciences Essay

Dams are built for assorted intents ; the major map includes hydroelectric power coevals, imbibing H2O supply, irrigation, inundation control, diversion etc. But the different incidents and surveies done by several research workers proved that these big dikes made for these intents, besides at the same time pose significant menaces to the life, belongings and the environment throughout their lifecycle. The impacts may be different in different stages, viz. building, operation and decommissioning stage. There are about 845,000 dikes around the universe ( Jacquot, 2009 ) , the cumulative impact of all these dikes could be tremendous. So, it is indispensable to understate the impacts due to dam building on lives, belongings and environment. Identifying possible impacts, ciphering hazard and understating the hazard through the acceptance of assorted techniques could assist to take down the overall impacts. Major jeopardies associated with Dams throughout their lifecycle ( Reservoir ) : Construction Phase: Construction of big substructure like dikes demands monolithic sum of building stuff, digging procedure and vehicles, which straight impacts on the environment and society. Most of the equipments and vehicle engage on such activities use fossil fuel as the chief beginning of energy and contribute to the green house gas emanation. The estimated emanation from Glen Canyon dike during its building stage was calculated as 800,000 metric dozenss of CO2 equivalent ( Pacca, 2002 ) . The hazard of accidents due to the vehicles, building activity and digging procedure to the worker is likely. The building site could be of particular involvement for some animate being or works, so this activity may take to the disappearing such plant/animal from that country for of all time. Operation Phase: The operation of dikes besides poses menace to the environment and people. The menace of dam failure during the operation stage due to assorted grounds may do immense loss of life and belongings. There is ever menace of drawing of people on the dike. The emanation during this stage from the decay of biomass in the reservoir is obvious ; the emanation from the Glen Canyon dike during its operation stage was estimated to be 3,500,000 metric ton of CO2 equivalent ( Pacca, 2002 ) . The failure of dike is the most destructive event of the full lifecycle of dike. The inside informations on dike failure are discussed individually below. Decommissioning Phase: This is the last phase of the life rhythm of dike, this phase pose menace of brushing the downstream countries ( colonies, substructure, etc ) and the lives. The emanation from this phase is found as largest in comparing with building and operation. The emanation from the decommissioning of the Glen Canyon dike was calculated as 33,000,000 metric dozenss of CO2 equivalent ( Pacca,2002 ) , which was more than nine times the emanation from the full operation stage. Though the decommissioning work is done in controlled mode, the loss of belongings would non be as the dam failure. Environmental and Social effects throughout a dike ‘s life: Construction Phase: Resettlement of people: Construction of Dam requires immense country of land, which is frequently acquired by displacing people from that topographic point. Peoples are frequently forced to go forth their familial land giving them psychological emphasis and the relocation to the new location frequently alters the bing environment at that place. In China Three Gorges Dam have already displaced a million people and still another 80000 are to be moved till its concluding phase, 1200 small towns and 2 major towns have had to be abandoned and rebuilt ( McGivering, 2006 ) . Archaeological sites: In some instances even the archeological sites besides get destroyed due to dam building. More than 100 archeological sites, some dating back over 12000 old ages is to be submerged due to the three gorge dike ( Gleick, 2009 ) . Transportation, digging and building: The motion of vehicles during the building of dike contributes to emission to some extent and every bit upset the ecology at that place. The digging and building procedure both impact the ecology locally. Air pollution due to the dust can be expected. Operation Phase: Siltation: Rivers carry sediment tonss, the sum vary harmonizing to the features of the catchment country and the speed of the running H2O. The building of dike reduces the speed of the river therefore assisting deposit to settle down within the reservoir. If the deposit shortage issue due to this in river, the channel can be expected to evacuate deposit from its bed and Bankss in the downstream set uping the environment at that place ( Grant,2003 ) . Methane Generation: Hydro power was considered to be the renewable that produce no nursery gases. Harmonizing to Boyle, G ( 2009 ) , a study by the universe committee on dikes ( WCD, 2000, Anon, 2001 ) , the decaying of vegetable affair in an anaerobiotic status produces methane ( CH4 ) , when the land is flooded with hydro undertaking. Fish migration: Fish are affected straight by the obstructor like dike on its class. The most normally affected species like Salmon, which needs to travel upriver for engendering, can be obstructed from their spawning topographic point. Flood of the engendering evidences within the reservoir, periodic flood and drying out of engendering land and refuge country downstream of the dike farther shackles the fish ‘s activity. ( Harvath, and Municio,1998 ) . Birthrate of the downstream plains: The downstream portion of dike loose the food incorporating dirt, which used to have during implosion therapy. After the edifice of the Aswan dike, in 1960 ‘s, the land downstream no longer receives the dirt and foods antecedently carried by the one-year Nile inundation. The agricultural system has been destroyed in the downstream and to be replaced and is replaced by irrigation and chemical fertiliser ( Boyle, 2004 ) . Local clime alteration: Increased precipitation has been observed after the building of dike, the physical procedure by which big graduated table surface vaporization triggers in the precipitation recycling in such country ( Hossain, et Al, 2009 ) . Changes in the air wet per centum, air temperature, air motion in large graduated table can be caused by large graduated table dike ( Tahmiscioglu, et Al, †¦ . ) . Impact on biodiversity: In some instances edifice of dike disturb the home ground of critically endangered species excessively, the winter shelter of Siberien Crane and the ‘Baiji ‘ Yangtze river mahimahi, are found to be affected by the three gorges dam ( hypertext transfer protocol: //en.wikipedia.org/wiki/Three_Gorges_Dam ) . Induced temblors: big reservoirs can do seismal events as they fill, as the force per unit area on local mistakes additions ( ICE 1981 ) . The seismal activity of magnitude 5.7 was recorded in Lake Oroville in Butte county of California in June 1982 ( Allen, 1982 ) . Agricultural/ loss of woods: In many instances, the building of dike covers the productive agricultural land which used to be the agencies of nutriment for the local people and in many instances clear some portion of wood destructing natural ecosystem. About 1400 Hector of agricultural land is to be submerged because of the three gorge dike ( Gleick, 2009 ) . Spread of disease ( addition in disease carrying vectors, e.g. mosquito ) : Study carried out by Yewhalaw, et Al ( 2005 ) , found that the impounding can move as genteelness land for vectors like mosquito, and found that the kids populating near to dikes are at greater hazard of plasmodium infection than the kids populating off. Decommissioning Phase: Decommissioning: Even though, decommissioning of dikes help to reconstruct the reverine ecosystem to its natural status, some short term negative consequence such as sediment mobilization, contaminated stuff and menace of ace impregnation can be seen ( Bednarek, 2001 ) . Dam Failure: One of the most evidently harmful consequence of big dike is seen, when it falls. The implicit in causes may be different in each instance. Some of the major causes are ( ICOLD, 1973 ) : Dominating Foundation defects Shrieking and ooze Conduits and valves Seismic event harm Failure of dike due to internal H2O force per unit area Failure of dike due to drawn-out period of rainfall and implosion therapy Causes of Dam Failure that occurred between 1075- 2001 ( NPDP, 2007 ) ( Adopted from historic records of Dam Performance, 2007 ) On the footing of the above graph it can be said that, flood or dominating of the dike wall stand far in front from other causes of dam failure. Seepage and piping is on 2nd place and remainder of all are responsible for really less figure of dam failures, this graph proves that the overtopping of dike is the major causes of dam failures. Cost of Dam Break: The cost of dam interruption consists of two constituents ; Reconstruction cost of dike and economic loss due to devastation and flood downstream ( Kuo, et Al, 2008 ) . Cost and Benefit from Dam: Dam building is an expensive work and demands immense amount of money, but it provides highly necessary things for running the society and development like energy and H2O for imbibing and irrigation intent. On the other manus it has some impacts on society and environment, some of which needs tonss of money and clip for Restoration while others are irreparable. So building of dike has its ain pros and cons. Wayss to understate the happening of dam failure: Dam failure is the most destructive incident in the full life rhythm of dike, which may do immense loss of life and belongings. So it is indispensable to guarantee the safety of dike in order to protect the life and belongings. Some of the of import stairss indispensable for the decrease of dam failure and its impacts are as follows ( MDE, 1996 ) : Rigorous statute law should be promulgated by authorities for the building of dam/ Reservoir. Everyday distortion monitoring of ooze from drains in and around larger dike is necessary and if found faulty, disciplinary step should be taken. In instance of wall break, stone grouting ( force per unit area pumping of cement slurry ) can be done to cut down the hazard of dam failure. Regular monitoring and care could assist a batch to forestall dam failure. Early on warning system should be incorporated in the reservoir system to protect people and belongings downstream, in instance of dam failure. Dam building should non be allowed in the country of high seismal activity. Most of the states make safety programme for the protection of dike. In USA most of the ‘states ‘ are responsible for the safety of dikes within their boundary and to guarantee the safety they on a regular basis follow the undermentioned process ( Lane, 2008 ) ; Measure the safety of bing dike. Review programs and specification for safety and regulative programme. Carry out periodic review on building on new and bing dikes. Review and blessing of exigency action program. Some steps to cut down other impacts on and due to dikes: Management of catchment of river can assist to cut down deposit on dike, which may include plantation on the catchment country, acceptance of landside and eroding control measures for the upstream country of dike. The periodic cleansing of dikes can assist to cut down the burden of deposits within a dike and aid to repossess the capacity to its original signifier. Fish ladder can assist to reconstruct fish migration to some extent. ( beginning ) The computation of likely maximal precipitation ( PMP ) and appraisal of likely maximal inundation ( PMF ) and the chance of mean return period for that river, could assist to plan the dike decently ( CSCD,1985 ) , which could forestall dike from failure. Monitoring should be carried out to command the genteelness of mosquitoes in dike, if found, mosquito larvae must be controlled with the sanctioned mosquito larvicide, so that the other aquatic being will hold minimum impacts from larvicide ( DHF,2006 ) . Rich image of Dam and associated Impacts A Rich Picture exemplifying impacts of dike on assorted facets of environment and society Hazard of Dam Failure with age: Percentage of different age groups of dike failures in Russia in comparing with the failures of universe dike. ( Adopted from Management of Impounded Rivers, Wang and Melching, 2007 ) . Though age is one of the of import factor for the dam failure as the walls and other substructures erodes or weakens with age, but it is non merely the factor that causes dam failure ; faulty constructions, utmost conditions events, sabotage, seismal activities etc besides trigger to dam failure. The above graph showed that the highest figure of dam failure was in the age group 0-10, which so bit by bit decreases as the age group increases. The faulty construction can take to dam failure even at its early age while the good constructed and good maintained dike can function over hundred old ages. On the footing of above graph it can be said that aging in non the primary factor for dam failure and proper care can lengthen the life span of dam despite of age, and does non demo clear correlativity with dam failure. One likely ground of less figure of dam failures of the aged dike could be the proper care and decommissioning before the dike failure occurs. Risk Assessment of dam failure: Risk appraisal was calculated on the footing of informations from Annex-3. High badness status Entire Occurrence= 11 Average clip taken to reiterate the events for the category IA ( with more than 300 deceases ) =11.1 twelvemonth Average Death calculated=1111.1 Risk=Frequency ( event/ unit clip ) -Magnitude ( Deaths ) =1/11.1-1111.1=0.09-1111.1=99.99 Therefore, Risk=99.99 per 11.1 twelvemonth Hazard computation for overall dike failure Entire happening of dike failure=46 Average spread between consecutive events=0.39 twelvemonth Average decease per event=357.91 Risk= Frequency ( event/ unit clip ) -Magnitude ( Deaths ) Therefore, Risk= 1/0.39-357.91=2.6-357.91=930.5 individual per 0.39 twelvemonth Decision: Mentions: Allen, C, R, 1982, Reservoir Induced Earthquakes and Engineering Policy, California Geology, 35, 11 Bednarek, A, T, 2001, Undamming Rivers: A Review of the Ecological Impacts of Dam Removal, Environmental Management, 27,803-814. Boyle, G, 2004, Renewable Energy: Power for a Sustainable Future, Oxford University, Oxford CSCD,1985, Safety of Dams: Flood and Earthquake Criteria, National Academy Press, Washington D.C. DHF, 2006, Guidelines for Preventing Mosquito Breeding Sites Associated with Aquaculture Development in NT, Department of Health and Families, Darwin Gleick, P.H. , 2009, Three Gorges Dam Project, Yangtze River, China, Water Brief, 3, 139-150. Grant, E, G, et Al, 2003, A Geological Framework For Interpreting Downstream Effects Of dikes On Rivers, Water Science and Application 7, 209-225 Harvath, E, and Municio, M. A. T.,1998, 2nd International Symposium in Civil Engineering, Budapest Hossain, F, et Al, 2009, Local Climate Change, EOS, 90,453-468 hypertext transfer protocol: //en.wikipedia.org/wiki/Three_Gorges_Dam, assessed on 4 March, 2010. hypertext transfer protocol: //www.internationalrivers.org/files/srdamsafety.pdf, assessed on 20 May, 2010 hypertext transfer protocol: //npdp.stanford.edu/npdphome/Historic % 20Performance % 20of % 20Dams.pdf, assessed on 20 May,2010. hypertext transfer protocol: //www.damsafety.org/ , assessed on 20 March, 2010 International Committee on Large Dams ( ICOLD, 1973 ) , Lessons from Dam Incidents, Reduced Edition, Paris Jacqot, J,2009, Numbers Dams ; From Hoover to Three Gorges to the crumbling 1s, Environmental Policy, hypertext transfer protocol: //discovermagazine.com/2009/mar/08-dams-hoover-three-gorges-crumbling-ones, assessed on 17 May 2010. Kuo, J, T, et Al, 2008, Dam Over Topping Risk Assessment Considering Inspection Programme, Stoch Environ Res Risk Assess, 22, 303-313 Lane, N, 2008, Aging Infracture: Dam Safety, Congressional Research Service McGivering, J, 2006, Three Gorges Dam ‘s Social Impact, BBC, hypertext transfer protocol: //news.bbc.co.uk/1/low/world/asia-pacific/5000198.stm, assessed on 3 March 2010. MDE, 1996, Maryland Dam Safety Manual, Association of State Dam Safety Officials Pacca, S, 2007, Impacts from Decommissioning of Hydroelectric Dams: A life Cycle Prospective, Climate Change, 84, 281-294 Tahmiscioglu, M, S, et Al, .. Positive and Negative Impacts of Dam on the Environment, International Congress on River Basin Management, 760-769 Wang, Z, Y, and Melching, S, 2007, Management of Impounded Rivers Yewhalaw, D, et Al, 2005, Malaria and Water Resource development: The Case of Gilgel-Gibe Hydroelectric Dam in Ethopia, Malar. J, 8, 21 Annex-1 ( Part-A ) PLAGARISM DECLARATION I declare that the work I am subjecting for appraisal contains no subdivision copied in whole or in portion from any other beginnings unless it is explicitly identified by agencies of citation Markss. I declare that I have besides acknowledged such citation by supplying elaborate mentions in an sanctioned format. I understand that either or both unidentified and unreferenced copying constitutes plagiarism, which is one of a figure of really serious offenses under the university ‘s codification of pattern on the Use of Unfair Means. Student No- 200910979 LIFE CYCLE ANALYSIS OF A DAM CONTENTS PAGE NO. Introduction: 3 Major jeopardies associated with Dam: 3 Major environmental issues associated with dam 3-4 Catastrophes ( Dam failure ) : Siltation Methane coevals Fish migration Resettlement of people Birthrate of the downstream fields Local clime alteration Impact on biodiversity Induced temblors Agricultural/ loss of woods Spread of disease Archaeological sites Decommissioning Cardinal inquiries for portion B 5 Draft Plan 5 Mentions 6 Word Count- 1076 Word Limit- 1000 Introduction: Dams are built for assorted intents ; the major map includes hydroelectric power coevals, imbibing H2O supply, irrigation, inundation control, diversion etc. But the different incidents and surveies done by several research workers proved that these big dikes made for these intents, besides at the same time pose significant menaces to the life, belongings and the environment throughout their lifecycle. The impacts may be different in different stages, viz. building, operation and decommissioning stage. Yes, but what is th eproblem state of affairs or concern? Major jeopardies associated with Dam: Dam failure: one of the most evidently harmful consequence of big dike is seen, when it falls. The implicit in causes may be different in each instance. Some of the major causes are: Seismic event harm Failure of dike due to internal H2O force per unit area. Failure of dike due to drawn-out period of rainfall and implosion therapy. Menace to human life due to submerging in dike. Major environmental issues associated with dike: Catastrophes ( Dam failure ) : Dam failure frequently consequences immense loss of life, belongings and environment. During twentieth century some 200 dike failures caused more than ten 1000 people outside China and in the twelvemonth 1975 merely about one-fourth of million people were perished in the series of hydroelectric dam failure in China ( Boyle, G, 2004 ) . Siltation: Rivers carry sediment tonss, the sum vary harmonizing to the features of the catchment country and the speed of the running H2O. The building of dike reduces the speed of the river therefore assisting deposit to settle down within the reservoir. If the deposit shortage issue due to this in river, the channel can be expected to evacuate deposit from its bed and Bankss in the downstream set uping the environment at that place ( Grant,2003 ) . Methane coevals: Hydro power was considered to be the renewable that produce no nursery gases. Harmonizing to Boyle, G ( 2009 ) , a study by the universe committee on dikes ( WCD, 2000, Anon, 2001 ) , the decaying of vegetable affair in an anaerobiotic status produces methane ( CH4 ) , when the land is flooded with hydro undertaking. Fish migration: Fish are affected straight by the obstructor like dike on its class. The most normally affected species like Salmon, which needs to travel upriver for engendering, can be obstructed from their spawning topographic point. Flood of the engendering evidences within the reservoir, periodic flood and drying out of engendering land and refuge country downstream of the dike farther shackles the fish ‘s activity. ( Harvath, E, and Municio, M. A. T.,1998 ) . Resettlement of people: Construction of Dam requires immense country of land, which is frequently acquired by displacing people from that topographic point. Peoples are frequently forced to go forth their familial land giving them psychological emphasis and the relocation to the new location frequently alters the bing environment at that place. In China Three Gorges Dam have already displaced a million people and still another 80000 are to be moved till its concluding phase, 1200 small towns and 2 major towns have had to be abandoned and rebuilt ( McGivering, 2006 ) . Birthrate of the downstream plains: The downstream portion of dike loose the food incorporating dirt, which used to have during implosion therapy. After the edifice of the Aswan dike, in 1960 ‘s, the land downstream no longer receives the dirt and foods antecedently carried by the one-year Nile inundation. The agricultural system has been destroyed in the downstream and to be replaced and is replaced by irrigation and chemical fertiliser ( Boyle, G, 2004 ) . Local clime alteration: Increased precipitation has been observed after the building of dike, the physical procedure by which big graduated table surface vaporization triggers in the precipitation recycling in such country ( Hossain, F, et Al, 2009 ) . Changes in the air wet per centum, air temperature, air motion in large graduated table can be caused by large graduated table dike ( Tahmiscioglu, M, S, et Al, †¦ . ) . Impact on biodiversity: In some instances edifice of dike disturb the home ground of critically endangered species excessively, the winter shelter of Siberien Crane and the ‘Baiji ‘ Yangtze river mahimahi, are found to be affected by the three gorges dam ( hypertext transfer protocol: //en.wikipedia.org/wiki/Three_Gorges_Dam ) . Induced temblors: big reservoirs can do seismal events as they fill, as the force per unit area on local mistakes additions ( ICE 1981 ) . The seismal activity of magnitude 5.7 was recorded in Lake Oroville in Butte county of California in June 1982 ( Allen, C, R, 1982 ) Agricultural/ loss of woods: In many instances, the building of dike covers the productive agricultural land which used to be the agencies of nutriment for the local people and in many instances clear some portion of wood destructing natural ecosystem. About 1400 Hector of agricultural land will be submerged because of the three gorge dike ( Gleick, P.H. , 2009 ) . Spread of disease ( addition in disease carrying vectors, e.g. mosquito ) : Study carried out by Yewhalaw, D, et Al ( 2005 ) , found that the impounding can move as genteelness land for vectors like mosquito, and found that the kids populating near to dikes are at greater hazard of plasmodium infection than the kids populating off. Archaeological sites: In some instances even the archeological sites besides get destroyed due to dam building. More than 100 archeological sites, some dating back over 12000 old ages will be submerged due to the three gorge dike ( Gleick, P.H. , 2009 ) . Decommissioning: Even though, decommissioning of dikes help to reconstruct the reverine ecosystem to its natural status, some short term negative consequence such as sediment mobilization, contaminated stuff and menace of ace impregnation can be seen ( Bednarek, A, T, 2001 ) . Cardinal inquiries for portion B: Answer to the undermentioned inquiries will be searched in the 2nd portion of this instance survey: What are the major jeopardies associated with dike and how the hazard can be minimised? What are the attacks practised to understate the impact on dike on environment and homo? How the dike induced impact like deposit, obstructor on the fish migration path and addition in diseases bearer vector can be regulated? How the regulation organic structure guarantee the safety of dike? How the factors like political relations and economic system affect in the building of dike? Draft Plan: Introduction Major jeopardies associated with Dam ( Reservoir ) Causes of Dam failure The possible impacts of such jeopardies Measures to understate the impacts Environmental Issues associated with Dam Impact on agribusiness and wood Impact on fish migration Impact on biodiversity Measures practised to understate the impact Socio economic impact of Dam Abandonment and relocation of displaced people Damagess to ancient heritage ( archeological construction ) Wayss to understate the harm to ancient heritage Cost Benefit Analysis of Dam Decision

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