首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
Removing Dams P1: In the last century, many of the dams in the United States were built for water diversion, agriculture, factor
Removing Dams P1: In the last century, many of the dams in the United States were built for water diversion, agriculture, factor
admin
2018-10-18
26
问题
Removing Dams
P1: In the last century, many of the dams in the United States were built for water diversion, agriculture, factory watermills, and other purposes that allowed farming on lands that would otherwise be too dry, with low-cost hydroelectric power generation being a very significant side benefit. Building these dams was rather labor-intensive, which created jobs for workers and stimulated regional economic development. But those opposed to large dams can marshal a sobering array of criticisms based on those already built, which have provided some benefits but have without exception destroyed river environments and the human communities that depend on them.
P2: Many, perhaps most, of the more than 90,000 dams in the country are now obsolete, expensive, and unsafe, and were built with no consideration of the environmental costs. As operating licenses come up for renewal in 1999, habitat restoration to original stream flows will be among the options considered. As these dams age and decay, they can also become public safety hazards, presenting a failure risk and a dangerous nuisance. Worse still, with the growth of the American population, more people are moving into risky areas. Dams that once could have failed without major repercussions are now upstream of cities and development. In 1998, the Army Corps announced that it would no longer be building large dams. In the few remaining sites where dams might be built, public opposition is so great that getting approval for projects is unlikely.
P3: For many years, the United States Fish and Wildlife Service had advocated the removal of the Edwards Dam, which was built in 1837 on the Kennebec River in Augusta, Maine, to ease navigation and generate electricity. The Kennebec River was once home to all ten species of migratory fish native to Maine, along with several thriving commercial fisheries. Damming the river not only transformed the natural landscape, but it also prevented migration of salmon, shad, sturgeon, and other fish species up the river.
In 1999, the Federal Energy Regulatory Commission (FERC) refused the renewal of the dam license due to excessive negative environmental impact, and the dam was removed, freeing a 17-mile stretch of the Kennebec River that had been submerged for 162 years. P4: The cost of keeping outdated hydroelectric equipment running decades after it was installed or upgrading dam safety systems may not be worth it. This was proven true on the Elwha River in the Olympic National Park in Washington when an extraordinarily rich salmon habitat was being disrupted by an outdated hydroelectric plant. Before dams were built on the Elwha River, 400,000 salmon returned each year to spawn, but that number dropped to fewer than 3,000 after dams were put up. Once the hydroelectric power generating capacities of the dams had outlived their useful lives, the importance of this salmon habitat necessitated the removal of the dams on the Elwha River. Simply removing the dams will not restore the salmon, however. Where 50-kilogram king salmon once fought their way up waterfalls to lay their eggs in gravel beds, there are now only concrete walls holding back still water and deep beds of muddy deposits.
P5: When the negative environmental effects outweigh the benefits, a dam may be considered for removal. The Hetch Hetchy Dam, whose construction was one of the first major defeats of the nascent American environmental movement, was approved in 1913 to assist earthquake-ravaged San Francisco. Environmentalists and nature lovers, who said the valley’s beauty surpassed even Yosemite Valley’s, have constantly fought for its removal. They claim that restoring Hetch Hetchy Valley could reclaim an area that is half the size of Yosemite Valley and nearly identical in terms of beauty. Revenue and increased local spending from tourism could offset some or all of the losses from removing the dam. This problem can be thought of as appraising the relative value of two scarce resources, water and space, in Yosemite National Park.
P6: How does one weigh the many different economic, cultural, and aesthetic considerations for removing or not removing these dams? Do certain interests, such as the rights of native people or the continued existence of native species of fish or wildlife, take precedence over economic factors, or should this be a utilitarian calculation of the greatest good for the greatest number? And does that number include only humans, or do other species count as well?
P4: ■ The cost of keeping outdated hydroelectric equipment running decades after it was installed or upgrading dam safety systems may not be worth it. ■ This was proven true on the Elwha River in the Olympic National Park in Washington when an extraordinarily rich salmon habitat was being disrupted by an outdated hydroelectric plant. ■ Before dams were built on the Elwha River, 400,000 salmon returned each year to spawn, but that number dropped to fewer than 3,000 after dams were put up. ■ Once the hydroelectric power generating capacities of the dams had outlived their useful lives, the importance of this salmon habitat necessitated the removal of the dams on the Elwha River. Simply removing the dams will not restore the salmon, however. Where 50-kilogram king salmon once fought their way up waterfalls to lay their eggs in gravel beds, there are now only concrete walls holding back still water and deep beds of muddy deposits.
According to paragraph 3, why did the United States Fish and Wildlife Service want the Edwards Dam removed?
选项
A、Because the age of the dam made it unsafe.
B、Because the dam was negatively affecting various species of fish.
C、Because the dam had caused wetlands to form.
D、Because the dam no longer provided economic benefits.
答案
B
解析
【事实信息题】本页最后一句提到很多年来,美国鱼类及野生动物管理局一直提出要拆除这个大坝。因为它阻碍了很多鱼类的迁徙。
转载请注明原文地址:https://jikaoti.com/ti/QPhYFFFM
0
托福(TOEFL)
相关试题推荐
Completethenotesbelow.WriteNOMORETHANTWOWORDSAND/ORANUMBERforeachanswer.BirminghamexhibitionExampleAnswerPur
Completethenotesbelow.WriteNOMORETHANTWOWORDSAND/ORANUMBERforeachanswer.BirminghamexhibitionExampleAnswerPur
Listentothedirectionsandmatchtheplacesinquestions11-15totheappropriateplaceamongA-Eonthemap.HealthCentre
ChooseTHREEletters,A-G.WhichTHREEfactorsshouldthestudentconsiderwhileselectingcourses?AclasstimeBcoursetopic
Completethesentencesbelow.WriteONEWORDONLYforeachanswer.FootballintheUKPriortothe19thcentury,footballplaye
Choosethecorrectanswer,A,BorC.Camber’sThemeParkAccordingtothespeaker,inwhatwayisCamber’sdifferentfromothe
Whichofthefollowingquestionsdoesthepassageprimarilyanswer?Theword"they"inline25refersto
Whatdoesthepassagemainlydiscuss?Theword"it"inline12refersto
Manyscientistsbelieve______asaresultofacollisionbetweenthenewlyformedEarthandalargeasteroid.
WATERANDLIFEONMARS1Thepresenceorabsenceofwaterhasadirectbearingonthepossibilityoflifeonotherplanets.In
随机试题
提高社会主义经济效益,就是以尽量少的投入,获得尽可能多的产出。()
关于非特异性投射系统的叙述,哪一项是正确的
酸性汗液见于____________和长期服用____________药物的患者。
A、毛玻璃样细胞B、上皮样细胞C、伤寒细胞D、AnitsChkow细胞E、R-S细胞慢性乙型肝炎时可见
合同解除,是指合同有效成立后,尚未履行前,具备合同解除条件时,因当事人双方的意思表示而使合同关系归于消灭的行为。( )
股东大会是股份公司的权力机构,由()组成。
债权人为了防止其利益被股东或经营者伤害,可以采取的措施有()。
会计凭证的传递是指会计凭证从取得或填制时起至归档保管过程中,在单位内部会计部门和人员之间的传递程序。
瓷器:黏土
党的十八届四中全会指出,全面推进依法治国,总目标是()。
最新回复
(
0
)