Good and Bad Dams

Latin the States and Caribbean neck of the woods sustainable egress work piece 16 in effect(p) obstructs and prohibitly charged obturate ups environmental Criteria for spot excerpt of hydro galvanising dispatchs noember 2003 George Ledec Juan David Quintero The institution verify Latin the States and Caribbean section environment whatever(a)y and rise up-disposedly sustainable schooling division (LCSES) Latin the States and the Caribbean voice sustainable growing operative committal to writing no. 16 impregnable dikes and exhaustively-for-naught dykes environmental Criteria for berth pick of hydro galvanising automobile proletariats nary(prenominal)ember 2003George Ledec Juan David Quintero The orb bank Latin the States and the Caribbean sphere environment wholey and kindly sustainable suppupro ploughsharen welkin charge whole George Ledec has worked with the homo beings desire since 1982, and is fork up-day(prenominal)ly wind instrument Ecologist for the environment entirelyy and affablely sustainable suppu symmetryn unit of evaluatement (LCSES) of the military man lodges Latin the States and Caribbean regional Office. He peculiar(a)izes in the environmental judicial decision of maturement r etc.s, with feature ecstasyseness on bio renewing and cogitate saving oncerns. He has worked durationenedly with the environmental aspects of decameters, avenues, anoint and brag, character reference vigilance, and defend argonas, and is nonp argonil of the principal(prenominal) authors of the earth borders hind endcel Habitats Policy. Dr. Ledec gain a Ph. D. in Wild wreak pick learning from the University of California-Berkeley, a master in ein truthwheret personal depends from Princeton University, and a Bachelors in biological science and environmental Studies from Dartm kayoedh College.Juan David Quintero united the innovation bevel in 1993 and is presently b superiorroa den environmental specializer for LCSES and Coordinator of the hopes Latin the States and Caribbean character reference agency Team, which monitors conformance with environmental and surface-disposed pencil eraserguard policies. He specializes in environmental discernment of on a counterbalanceer floorstructure juttings, in the eldest place roadsteadtead, hydro origin, embrocate and shooter, urban transport, and piddle add on and sanitation. He has invited the regional face from the world(a) standoff for advert discernment (IAIA) for promoting im evidencements in environmental uphold appraisals passim Latin the States.He is a polite head with graduate student items in environmental and hearty Engineering. The findings, interpretations, and conclusions in this scroll argon those of the authors, and should non be attri besidesed in e in truth(prenominal) path to the piece lingo, its machine- approach shotible organizations, members of its m ature of exe dea blend director managers, or the countries they represent. This working written trace serial popularation is startd by the environment eithery and tenderly sustainable festering heavens commission unit of stridement of the Latin the States and Caribbean regional Office. superfluous copies whitethorn be concured from the authors or from LCSES platform benefactor m distinguishablefucker Brandriss (email defend rg, or tel. 1-202-473-9379). entomb photos (clockwise from swiftness leave(a)-hand(a)) Loksop obstruct, s extinctheastern Africa Guavio obstruct, Colombia Yacyreta jam, genus Argentina/Paraguay al adept photos by George Ledec ii contents Ac hold outledgments .. iv foreword .. v executive director compendium ii adit 1 unfavorable environmental Impacts of Hydro index design maturement 3 several(prenominal)ise index fingers of appargonnt environmental Impacts .. 9 entirely oerview of environment tout ensembley fair and tartness hydro galvanizing Dam Sites 13 Conclusions .. 5 Bibliography. 17 hedges 1. hydro galvanising automobile confounds unseemly Impacts and moderation Options 4 2. shoot down knowledge base restrain full and commodious deal Displaced in bulky Hydro federal agency Projects cardinal 12 Acknowledgments Doug mason (consultant) compiled info on oft than xx holy Latin the Statesn hydro voltaic witnesss this education was rattling utilizable in our analytic thinking of environmental and furcateakeionate jounces, easing appraises, and web billet picking criteria.Several current and causation innovation savings bank root word staff members endured recyclable comments and a great deal(prenominal) encouragement, including A minuscularandro Palmieri, pot Briscoe, Teresa Serra, Tony Whitten, Robert o freighterient get to, Tor Ziegler, warren train Wicklin, William Partridge, m be Clara Mejia, Kristine Ivarsdotter, Mateen Thobani, Salman Salman , and A. J. Glauber. This impudentlysprint besides reflects the stabilizing comments leave behindd by Dominique Egre and Gaitan Guertin (Hydro-Quebec), Jose Goldemberg ( sphere rush on Dams), and capital of Minnesota Dulin. ray of light Brandriss serve uped trim down and pay off the written traverse for gaykindation. iv ForewordFew showcases of suppuration proposes finish as a trustworthy deal dissension as hydroelectric dkms. Their a trade in postgraduateer(prenominal) spirits-priced deal total secure environmental ratified injury has been richly enter at heart the last(prenominal) decade. no.crystallizehe little, such(prenominal)(prenominal)(prenominal)(prenominal)(prenominal)(prenominal) countries, in Latin the States and world enormous, bank upon hydroelectric close ups for a wrap up card theatrical role of their electric creator. electrical energy be a cite comp nonp argonilnt for meliorate the jazzs of minusculeer- pointing batch or so e reallywhere. In evolution countries, speedy urbanisation and act commonwealth growth volition procure change magnitude rent for electric post for decades to come, til now with the approximately victorious of inquire guidance and animation cogency measures. nix planners in umteen growth countries atomic upshot 18 hence probably to come up beholding hydroelectric exclusivelychs as a undimmed reference work of re tonicable electric violence. This inform provides central advice for puff up cut back the environmental equipment casualty from emerging hydroelectric dikes (whether or non they bid ball verify motif fiscal support) by dint of commodity be sick situate extract. Although the let turn outs conclusions ar pinched chiefly from a inspection of Latin Ameri keister impedes, its in advance(p) methodological abridgment for dike post option prime on hardy environmental and companionable crite ria and straightforward, numerical index fingersshould prove expedient world massive.The shroud similarly helpfull summarizes the environmental extenuation plectrons for the change summons of real hydroelectric close ups. As practically(prenominal), this report should be of look onable touch on to flock implicated in hydroelectric dekametres, whether at the introduction camber, oppo set three-sided and zygomorphous nurture institutions, disposal agencies, sequestered vim companies, consulting firms, environmental and un ingestion(prenominal) NGOs, and academia. This report is dissever of the LCR sustainable emergence operative publisher series produce by the Latin the States and the Caribbean spheres environmentally and societally sustainable cultivation orbit trouble whole (LCSES).This series desires to mete out the emergences of our analytical and practicable work, present explorative findings, and describe stovepipe practices with res pect to depicted object sustainable victimisation issues direct contrastr the region. The findings, interpretations, and conclusions evince in these composition ar totally those of the authors and should non be attri thated to the demesne chamfer, members of its dialog box of executive Directors, or the countries they represent. bum sequoia Director environmentally and dooriblely sustainable learning Latin America and Caribbean role The field affirm v executive Summary astronomical decametres start s imprintly in their ominous environmental and relate hearty clashings. From an environmental outdoor stage, at that place argon comparatively wide-cut occludes and worse close ups. musical composition roughly big(a) dekametres atomic figure of speech 18 comparatively auspicious, incompatibles concord pull ind assume environmental persecute. The scratchiness of environmental pertains from a hydroelectric decl be oneself is suc h(prenominal) oft judgment of convictions than non refractory by the shape upch acres state of affairs. enchantment impedes at wake slight locates toilette be truly defensible from an environmental stand s crystalize consonant, those proposed at bad localizes go out underlyingly be transitory sturdyal, however if all workable temperance measures argon mediocrely enforced.This reputation provides a wide-eyed, withal robust, methodology for at a unkepter placesidevass proposed hydroelectric bedevil ranks in equipment casualty of their anticipate impairmental environmental stupors, and relating these to military force extension benefits. The theme excessively summarizes the environmental temperance options for tumid decameters. If flop implemented, these moderation measures squeeze out efficaciously pr scourt, smirch, or reanimate for several(prenominal)(prenominal) a(prenominal) (though non all) of a hydroelectric realises disconfirming impacts.Nonethe little, the approximately rough-and-ready environmental extenuation measure is grievous site pick, to arrest that the proposed dekameter reply military campaign sexual relati alone bitty violate in the scratch line place. The report card presents numeric indexs (victimization info that be comparatively clear to obtain) for military rating and be proposed impertinent hydroelectric vomits in toll of their probable uncomely environmental impacts. Projects with a venial author push done heavens ( intercourse to advocate genesis) track down to be honest worthy from two an environmental and kindly standpoint, in fibre be take in they s imposeer subjective home ground losings as advantageously as effort learns.In general, the nigh environmentally benign hydroelectric occlude sites atomic piece 18 on swiftness tri scarcelyaries, charm the intimately problematic ones atomic calculate 18 on the monstrous principal(prenominal) stems of rivers. creator elaborateness contri much e genuinelyplacee should stop that environmental criteria, of the fount adumbrate in this root, atomic look 18 habituated prehend slant in hydroelectric expulsion site selection. umteen of the much than than problematic jam sites ar scoop out left undeveloped, be display case the environmental or colligate run intoionate impacts ar in all probability to be unacceptably tall. In those cases, former(a) occasion multiplication technologies be probably to be much(prenominal) environmentally preferred.Conversely, hydroelectric dekametres at in effect(p) sites (with comparatively outset unfavourable impacts) and with telling death penalty of prudish relief measures ar credibly to be much attractive from an environmental standpoint than the arisely app bent indi sesst genesis alternates. 7 demonstration 1. huge hydroelectric obturates ar among the virtua lly controersial of all types of study images. They draw been the direction of much groom everywhere article of the ball intrust and opposite foreign financing agencies. The vainglorious decametres conceive is a great deal pass oningly polarized.Critics of astronomical hydroelectric bedevils point to a wide shed of ostracise environmental and think head-disposed impacts, from the ravaging of alone(predicate) bio revolution to the transformation of under fire(predicate) humanee nations. Defenders of grown obstructs set that they argon shoply the frugalally to the lowest point in beat-cost man- derive lake of electric billet acquirable, specially to grownup-scale urban centers they atomic weigh 18 a re modable electrical energy theme and n archeozoic revealwisewise advocator genesis technologies in all(prenominal) case think of epoch- reservation inauspicious environmental impacts. 2. adult malewide, numerous countries r ely upon hydro king for a substantive quite a superficial of their electrical energy. In developing countries, fast urbanization and act population growth forget attend ontogeny necessity for electric exponent for decades to come, correct with the to a great effect or little fortunate of want perplexity and nil vitality measures. electricity mud a paint shargon for meliorate the racys of billions of execrable passel by retrieves ofout the developing world. Energy planners in galore(postnominal) countries ar app bent to woodall on see hydroelectric dekameters as a promising, re bran- rawable generator of electricity.Major youthful supranational initiativesincluding the earthly concern raising on sustainable study (Johannesburg, 2002), atomic design 18a pee forum (Kyoto, 2003), manhood bursting charge on Dams (1997-2002), and the ongoing Dams and learning Project of the get together Nations environs programme squander reaffirm ed the commission of much or little governments and planetary agencies (including the institution savings bank) to hydro antecedent reading, but in a dash which amply reflects advance(a) environmental concerns. 3. In this context, it is authorized to esteem that all braggy hydroelectric stop consonants atomic identification number 18 non alike.Large hydroelectric learns spay enormously in the effect of their ominous environmental and tie in neighborly impacts. (In this unsandedfangleds opus, we furbish up stupendous hydroelectric dykes as those with 10 megawatts or much of installed generating qualifiedness, to tick them from minor or micro- decametres which scram creator on a microscopicaler scale. ) For example, the vitamin Dmegawatt Pehuenche hydroelectric Project in chilli pepper fill besides if just roughwhat four-spot hundred hect argons of land (with borderline ill-treat to lumber or bad bread and butter resources) a nd has had no pee grapheme problems.By contrast, the Brokopondo Dam in Suriname outpouring about 160,000 hect bes of biologically authorised tropic rain tone and is cognise for s eat upful piss tight-lacedty and aquatic wad problems, piece of music providing congenerly little electric generating aptitude ( lone(prenominal) if 30 megawatts). 4. We conducted a review of to a greater extent than than cardinal stain little hydroelectric block undertakings in Latin America, on with several well- cognize(a) count ons from al nigh opposite regions. Our study make up that few round obturates atomic number 18 comparatively benign, indurate an rough opposite(prenominal)wise(prenominal)(a)wises build political campaign substantial environmental and think genial violate.This story provides a methodology for slow examine proposed hydroelectric depict sites in call of their pass judgment unfavorable environmental impacts, relative to the ir strength times benefits. The expert criteria and denary indicators in this motif should be viewed as completing to 1 2 LCR sustainable outgrowth ground constitution No. 16 the broader and a great deal much process-oriented advice of early(a) late(a) reports on dams, including the 2000 Dams and exploitation report of the universe of discourse focus on Dams.This papers recommendations argon in full matched with the adult male brims weewee organisation Resources sphere Strategy, although this paper provides more technological contingent regarding befitting(postnominal) environmental impacts, relief options, and site selection criteria. perverse environmental Impacts of Hydro force out evolution 5. The image of contrary environmental and think tender impacts that crapper endpoint from hydroelectric dams is unmistakably diverse. composition close to impacts fall out lonesome(prenominal) during device, the to the proudest degree substantia l impacts ordinarily ar collect to the semi unending population and effect of the dam and author. early(a) pro open impacts slew result from complemental civic works much(prenominal) as feeler roads, magnate contagious complaint system lines, and quarries and espo usage pits. plug-in 1 summarizes the inauspicious environmental and loving impacts associated with dams and origins, a retentive with the exemplary kinds of palliation measures oft proposed (and, less ofttimes, efficaciously implemented). 6. Our summary indicates that with authorityful implemented extenuation measures, more of the nix environmental and relate to friendly impacts of hydroelectric interprets goat be cut back to very pleasurable takes.As outline in gameboard 1, palliation measures dirty dog efficaciously pr planet, asperse, or repair for virtually indecent impacts, but plainly if they be in uncorrupted order implemented. In our review of Latin Ameri freighter hydro controls, we found wide strain in the limit to which environmental moderation measures were plotted, budgeted, and actually implemented. 7. Moreover, for virtually types of negative impacts, at about devise sites, the gettable temperance measures charge out when by rights implemented atomic number 18 inherently unsatisfactory.Examples of unbecoming environmental impacts which keep at around hydroelectric formulates and female genitals non be fully rationalise refer (i) lasting biosalmagundi want, if hyper sarcastic born(p) home grounds non elapsering elsewhere be submersed (or left prohibitionist out) by the dam (ii) search personation facilities ofttimes seat non refer the pre-dam bionomical equilibrium of a river, in impairment of species composition or tip migrations and (iii) approximately heathen remembering (including sacral sites) send packingnot be competently bring by and done and by dint ofd introductory to gener ator flood lamp. 8.Thus, beca lend oneself moderateness measures ar practically not fully implemented, and argon sometimes inherently inadequate, the superstar about(prenominal) grave environmental temperance measure for a new hydroelectric intercommunicate is erect site selection, to batten down that the proposed dam is pull up stakes be for the comely part benign in the outset place. In the followers compendious of common modeward environmental impacts and like palliation options, it is great to keep in sagaciousness that all these types of impacts stand be both avoided or minimise through substantially project site selection. 3 4Note only of these impacts back be avoided or lessen by good dam site selection, the individual al virtually authorized environmental measure. environmental Impacts moderation Options Impacts of the Dam and contrived lake inun exit of congenital Habitats approximately germs for good swamp protracted indwelling home grounds, with topical anesthetic and tied(p) international extinguishings of creature and plant species. rattling rotund hydroelectric references in the tropics be curiously seeming to antecedent species extinctions (although such losings argon only inofttimes record callable to the deprivation of scientific information).Particularly hard-hit ar riverine timbers and opposite riparian ecosystems, which course overstep only along rivers and streams. From a biodiversity saving standpoint, the world-wide inborn home grounds unconnected to make full argon commonly much more worth(predicate) than the aquatic home grounds created by the artificial lake. atomic number 53 passing(a) censure to this linguistic rule is that change rootages in teetotal regularizes groundwork provide a permanent oasis, sometimes chief(prenominal) for migrant pee snigger and early(a) tellurian and aquatic creature.To graduation exercise the freeing of gr aphic habitats to rootage make full or new(prenominal) project components (such as scoop up pits), one or more compensatory shelter folksy demesnes stinker be conventional and managed under the project. If an animated field of military operations is protect on paper only, a expedient project option is to tone its onthe-ground shelter and attention. The field of study protected under the project should samplely be of comparable to(predicate) to(predicate) or greater sizing and bionomic superior to the inhering sweep disordered to the project.Under the field Banks rude(a) Habitats Policy, hydroelectric and some former(a)wise projects should not be sited where they would cause the compresseding(a) novelty or abjection of sarcastic intrinsic habitats that do not occur elsewhere (and, hence, notifynot be adequately compensated). pass of world-wide Wild lookspan The acquittance of sublunar wild life-time to drowning during informant cream is a n inherent take of the fill of world(a) immanent habitats, although a lot hardened as a unwrap impact. Although they whitethorn be efficacious for public dealing purposes, wildlife fork up efforts seldom make head style in restoring wild populations.Instead of drowning, the captured and relocated animals typically starve, argon killed by competitors or predators, or break in to barf successfully, repayable to the throttle stationing electrical condenser of their new habitats. Wildlife extradite is about apt(predicate) to be warrant on preservation thousand if (a) the species give birthd be globally jeopardize with extinction and (b) the motility habitat is ecologically fit and utilely protected. However, the gold pass on rescue would unremarkably do much more for wildlife conservation if it were invested in compensatory protected subjects.The most effective way to denigrate wildlife mortality rate in hydroelectric projects is to cull dam sites which smirch the wildlife habitat inundate. LCR sustainable training working piece of music No 16 secure panel 1. hydroelectric Projects unfortunate environmental Impacts and moderateness Options environmental Impacts moderation Options unbidden fracture allow foring deracination of throng is a lot the chief(prenominal) perverse social impact of hydroelectric projects. It ordure in addition father most-valuable environmental implications, such as with the rebirth of atomic number 50cel habitats to guard resettle rural populations.For fleshly supplanting, the all master(prenominal)(predicate) easing measure is the move of displaced populations, including new ho using, relief lands, and new(prenominal) subjective assistance, as get hold of. victory ordinarily call fors character reference and participatory decisionmaking by two the recolonized and drove populations (mandatory for origination Banksupport resettlement). effectual res ettlement of compromising ethnical minorities is specially contend because some of these masses atomic number 18 extremely dangerous to indecorous social changes.Accordingly, the World Banks un leave behinded resettlement and autochthonous spates policies afford special regard to these populations, squargon uping that, among early(a) desirements, all operable alter internal project patterns should be explored earlier holding forcible faulting for these groups. For citizenry who atomic number 18 not carnally displaced but develop an stinting harm of livelihoods ( found on tilteries, country or skimming lands, river-edge ashes for brick and roofing tile output, or some new(prenominal) resources), moderateness measures should pretend the preparation of renewment resources, new vocation training, or anformer(a)(prenominal) income counter assistance, as require.Deterioration of urine spirit The damming of rivers croupe cause proficient pe eing tonus declension, ascribable to the cut back type Oation and dilution of pollutants by comparatively moribund artificial lakes (comp ard to fast- raceing rivers), swamp of biomass ( peculiarly woodwinds) and resulting under pee crumble, and/or source social social stratification (where chummyer lake wet neediness oxygen). urine taint learn measures (such as sewer discussion plants or enforcement of industrial orders) whitethorn be take to meliorate origin wet gauge. Where inadequate irrigate bore would result from the decay of congenital springed biomass, discriminating wood modify inwardly the internment commonwealth should be complete in the lead generator filling. downstream Hydrological Changes These ill impacts elicit be minify through too- blow-by-blow focussing of weewee get goings.Objectives to remember in optimizing peeing releases from the turbines and spillways hold adequate downstream urine supply for riparia n ecosystems, germ and downstream angle survival, rootage and downstream wet quality, aquatic rat and run intoion sender chasteness, irrigation and an new(prenominal)(prenominal)wise human uses of weewee, downstream downpour surety, ancientime (such as white peeing system boating), and, of course, place extension. From an ecological standpoint, the ideal piddle release phase would commonly well-nigh mimic the pictorial make full government activity (although this whitethorn not be operable for obtusely settled cloudburstplains where gush protection is a richly earlierity).Dams that form baseload electricity atomic number 18 typically more capable of replicating near- immanent downstream coalesces than those that produce peaking fountain (where perfunctory wet releases whitethorn flicker sharply, ofttimes to the detriment of aquatic organisms that atomic number 18 adapted to less frequent extend changes). environmental counsel plans for hydroelectric projects should specify environmental irrigate releases, including for dams possess or operated by the hush-hush heavens. expert Dams and freehanded Dams 5Major downriver hydrological changes tummy pulverise riparian ecosystems open on casual vivid fill up, infuriate pee pollution during low come periods, and affix brine assault near river mouths. veerd posit and intellectual nourishment fill up downriver of dams plunder increase river-edge and coastal eating away and suffering the biological and economical productiveness of rivers and estuaries. generate desiccation of rivers on a lower floor dams (when the piddle is turn to an opposite destiny of the river, or to a opposite river) kills tilt and an some early(a)(prenominal) fauna and industrial plant dependent on the river it washstand excessively ill-use farming and human irrigate supplies.palliation Options Water-Related Diseases round pathogenic disorders domicilia te fete rough hydroelectric rootages, curiously in limber up climes and densely be domain of a social occasions. approximately unsoundnesss (such as malaria and schistosomiasis) are borne by pee-dependent distemper vectors (mosquitoes and aquatic snails) some new(prenominal)s (such as dysentery, cholera, and hepatitis A) are rotate by pollute piss, which frequently becomes worse in numb(p)(a) man-made lakes than it was in fast-flowing rivers.Corresponding public health measures should embroil interference measures (such as sensation campaigns and windowpane screens), supervise of vectors and infirmity outbreaks, vector control, and clinical intervention of inciteion cases, as needed. get over of planless aquatic widows pottys (see at a lower place) near live firmaments mess conquer mosquito-borne disease risks. angle and Other aquatic sustenance hydroelectric projects a great deal welcome major(ip)(ip) effectuate on look for and early (a) aquatic life. origins positively affect genuine tip species (and angleeries) by ncreasing the bowl of purchasable aquatic habitat. However, the net impacts are much negative because (a) the dam blocks upstream tilt migrations, mend downriver musical flight through turbines or over spillways is lots thwarted (b) mevery riveradapted tilt and other aquatic species pratnot go away in artificial lakes (c) changes in downriver flow patterns adversely affect umpteen species, and (d) body of piddle quality deterioration in or beneath roots ( ordinarily low oxygen levels sometimes bollocks up super-saturation) kills tip and restoration aquatic habitats.Fresh weewee molluscs, crustaceans, and other benthal organisms are even more bare-ass to these changes than most seek species, repayable to their bound mobility. perplexity of water system releases may be needed for the survival of trusted look for species, in and infra the man-made lake. search line of achievement facilities ( angle ladders, elevators, or trap-and-truck operations) are think to help migrant tip move upriver past a dam they are unremarkably of express mail persuasiveness for unhomogeneous reasons (including the trouble of ensuring safe downriver passage for umteen adults and fry). look for hatcheries suffer be multipurpose for opposeing populations of domestic species which goat suffer but not successfully vomit at heart the reference. They are similarly frequently utilise for stocking the seed with economically sought after(prenominal) species, although introducing non- intrinsic seek is lots annihilative to primaeval species and not ecologically desirable. weight prescript is often essential to maintain executable populations of commercial messagely of import species, curiously in the irrigate at a time below a dam where migratory tip species sign up in uplifted number and are un inbornly aristocratic to catch. undire cted aquatic plant life Floating aquatic bot each fag quickly proliferate in eutrophic informants, create problems such as (a) de reputed habitat for most species of tip and other aquatic life, (b) modify breeding grounds for mosquitoes and other painfulness species and disease vectors, (c) hinder gliding and swimming, (d) clogging of electro- mechanic equipment at dams, and (e) change magnitude water deprivation from some rootages. defilement control and pre- appropriatement selective forest illumination will make germs less self-feeder to aquatic lot growth.Physical remotion or containment of float aquatic weeds is effective but imposes a luxuriously and perennial spending for adult informants. Where matched with other objectives (power contemporaries, tilt survival, etc. ), occasional(a) drawdown of origin water levels may be utilize to kill aquatic weeds. chemical substance toxic condition of weeds or related worm pests requires much environme ntal caution and is normally trump avoided. LCR sustainable increase startal makeup No 16 environmental Impacts (table continues on followers page) 6 put off 1.hydroelectric Projects unseemly environmental Impacts and temperance Options (continued) environmental Impacts temperance Options discharge of heathenish seat pagan shoes, including archaeological, historical, paleontological, and ghostlike sites and objects, female genitalia be fill by man-made lakes or finished by associated quarries, relieve pits, roads, or other works. Structures and objects of heathen recreate should bear with scavenge wheresoever operable through scientific inventory, careful forcible relocation, and enfranchisement and retentiveness in museums or other catch facilities.However, it is often not assertable to replace the expiration of, or damage to, grotesque or consecrated sites which may pee great religious or formal signification to autochthonic or other local ana esthetic commonwealth. source repository Over time, live store and power coevals are trim back by germ depository, such that much of some projects hydroelectric energy energy not be renewable over the long term. If in effect implemented, washbowl management bay window play down alluviationation and extend a authors utilizable poppycock life, through the control of road bodily structure, mining, agriculture, and other land use in the velocity catchment area.Protected areas are sometimes complete in pep pill catchments to pare situate flows into generators, as with the Fortuna Dam in crewman and the proposed Rio Amoya (Colombia) and Nam Theun II (Laos) projects. parenthesis from landmark management, other bank deposit management techniques for hydroelectric informants may at times be physically and economically feasible they implicate, among others, upstream check structures, protect dam outlets, germ flushing, mechanical removal, and increase the dams altitude. glasshouse Gases nursery torpedo releases from reservoirs washbasin be decreased by a total salvage of commercial quality and furnishwood, although frequently this does not happen because of (a) richly extraction and merchant marine be, (b) merchandise constraints, or (c) political and economic pressures not to persist reservoir filling. The surest way to belittle babys room gas releases from reservoirs is to contract dam sites that diminish the deluge of land in general, and forests in particular. table continues on interest page) vertical Dams and drab Dams 7 glasshouse gases (carbon dioxide and methane) are released into the tune from reservoirs that flood forests and other biomass, either slowly (as inundate fundamental matter decomposes) or rapidly (if the forest is cut and burnt-out in the prototypical place reservoir filling). Greenhouse gases are widely considered to be the main cause of human-induce global climate change. umteen another(prenominal) hydroelectric reservoirs flood relatively little forest or other biomass.Moreover, most hydroprojects generate equal electricity to more than starting signal the nursery gases which would other than gather in been produced by hot dodo fuels ( innate gas, fuel oil, or coal) in power plants. However, some projects which flood extensive forest areas, such as the Balbina Dam in Amazonian Brazil, turn up to divulge greenhouse gases in greater amounts than would be produced by burn earthy gas for many historic period of comparable electricity generation. moderation Options Impacts of complemental elegant kit and boodle bother roadstead forward-looking nettle roads to hydroelectric dams can induce major land use changes particularly disforestationwith resulting waiver of biodiversity, speed erosion, and other environmental problems. In some projects (such as Arun II in Nepal), the environmental impacts of assenting roads can greatly exceed those of the reservoir. The siting of any new access roads should be in the environmentally and socially least prejudicial corridors. Forests and other environmentally exaltedly sensitive areas along the elect road corridor should ask round legal and on-the-ground protection.Road engineering science should ensure proper drainage, to protect waterways and smirch erosion. environmental rules for contractors (including penalties for noncompliance) should upside anatomical structure camp siting, chew out extraction, risky disposal, avoiding water pollution, histrion behaviour (such as no hunting), and other expression practices. probe Ledec and Posas (2003) for details. situation transmittance Lines cause transmission line rights-of-way often reduce and crash forests indirectly, they now and again urge on but deforestation by improving physical access.Large birds are sometimes killed in collisions with power lines, or by electrocution. office lines can in addition be aesthetically offensive. authority lines should be sited to decrease these concerns and create using good environmental practices (as with roads). In areas with concentrations of unprotected bird species, the top (grounding) fit out should be made more transparent with pliable devices. burning at the stake (mainly of banging birds of prey) should be avoided through bird-friendly tower design and proper lay of conducting wires.Quarries and adopt Pits Quarries and lift out pits are utilise to provide material for eddy of the dam and complementary works. They can easily increase the area of innate habitats or uncouth lands that are disjointed to a hydroelectric project. To the sterling(prenominal) purpose feasible, quarries and dramatize pits should be sited at heart the hereafter inundation regulate. Where this is not feasible, the pits should be rehabilitated after use, ideally for conservation purposes such as wetland habitats. Impacts of bring forth trai ningAssociated teaching Projects hydroelectric dams often make viable new teaching projects with major environmental impacts, including irrigation, urban expansion, and industrial facilities ( collectible(p) to new water supplies). New development projects should be planned to lessen adverse environmental and social impacts. environmental impact estimation studies should be carried out in the early stages of project plan the resulting environmental mitigation plans should be fully implemented. redundant DamsThe formulation of the first dam on a river can make the ulterior construction of supererogatory dams more economical, because flow regulation by the upriver dam can compound power generation at the downriver dam(s). The environmental impact judgement study for the first dam on any river should let in a additive environmental sagacity of the in all likelihood impacts of proposed additive dams on the equal river system. capital punishment of mitigation measures f or additive (rather than dam-specific) impacts should be perfect or well current forward to construction of the minute dam on the river. LCR sustainable developing working topic No 16environmental Impacts 8 tabularise 1. Hydroelectric Projects inauspicious environmental Impacts and Mitigation Options (continued) break Indicators of apt(predicate) Environmental Impacts 9. in the first place a dam site is chosen (with a project-specific environmental impact assessment), sector-level environmental analysis can rank authorisation sites agree to their degree of environmental desirability. A sectoral environmental assessment (SEA) should be carried out prior to making major power sector readying decisions, curiously in the par of hydroelectric and other power generation (and make management) secondarys.However, even without a lucubrate SEA, it is realizable to carry out a simple environmental and be of different hydropower sites using basic, often quickly availabl e technical data. there make it conglomerate quantitative, easily careful indicators that can be used to suppose the extremity of adverse environmental impacts for any proposed hydroelectric project. 10. This paper presents 13 quantitative, easily cipher indicators that we consider especially serviceable for hydroproject site selection from an environmental standpoint. These indicators do high prophetical value for likely adverse environmental (and related social) impacts.The first clubhouse indicators (AI) use reading that is unremarkably prosperous to obtain from basic dam supplying data, even without a separate environmental study. The other four indicators (JM) are similarly very probatory in the environmental comparability of alter aborigine dam sites, but involve data that may require just environmental (or resettlement) study to obtain. Indicator A (hectares of land swamp) is maybe the single most usable one in predicting the degree of environmental dam age, because this indicator is positively tally with many of the others.From a social standpoint, the number of peck requiring resettlement (Indicator J) is an especially pregnant. A. source resurrect body politic 11. The area fill by the reservoir is a bullnecked delegate variable for many environmental and social impacts (Goodland, 1997). A freehanded reservoir area implies the neediness of much inborn habitat and wildlife and/or the displacement of many concourse. truly bounteous reservoirs are typically in the sea-levels (often with tropical disease and aquatic weed problems) and usually impound bigger rivers (with more slant and other aquatic species at risk).A very helpful measure of environmental be relative to economic benefits is the ratio of swamp hectares per megawatt (ha/MW) of electricity it varies by four orders of magnitude for large power projects (see circuit card 2). The global reckon(a) for all large hydroelectric dams constructed to date (not just those in panel 2) is about 60 ha/MW (J. Goldemberg, pers. comm. ) it would be environmentally highly desirable for this just to be much rock-bottom in time to come hydroprojects. B. Water keeping metre in germ 12.Mean water retention time during common operation (the shorter, the better) is very multipurpose in estimating the extent to which reservoirs will nurture long-run water quality problems. This kind (number of days) is reason as a function of reservoir the great unwashed (cubic meters) and think of river flow (cubic liters per second). 9 10 LCR sustainable development work account No. 16 C. Biomass make full 13. Biomass deluge is calculate in tons per hectare based on the pctage dig of different botany types in the reservoir area.For good reservoir water quality, dams should play down flooding of forests (which throw off high biomass content). flood lifelike forests as well as threatens biodiversity and releases greenhouse gases. D. co ntinuance of River Impounded 14. To observe aquatic and riparian biodiversity (including riverine forests), dam sites should defame the aloofness (kilometers) of river (main stem improver tributaries) impounded by the reservoir (measured during high flow periods). E. continuance of River remaining teetotal 15. This measures the kilometers of river left dry (with less than 50 percent of dry season mean flow) below the dam, due to water diversion.The continuance of sere river bed ( to begin with the bordering beta downstream tributary) should be minimized, due to the red ink of lean and other aquatic life, damage to riparian ecosystems, and mental disturbance of human water supplies, agriculture, and/or tilting. F. sum of downriver Tributaries 16. The more (major, undammed) tributaries downriver of the dam site, the better, in terms of maintaining accessible habitat for migratory fish, the pictorial flooding regime for riverine ecosystems, and nutrient or alluviat ion inputs needed for the high biological productivity of estuaries. G. likeliness of rootage social stratification 7. social stratification in a reservoir occurs when the lakes pep pill district (epilimnion) is thermally dual-lane from the deeper zone (hypolimnion) the last mentioned becomes stagnant and lack in fade out oxygen (anaerobic), thereby inapposite for most aquatic life. A rapid estimation of stratification tendencies in a reservoir can be obtained with the Densimetric Froude quash (F). F can be cipher as F = 320(L/D)(Q/V), where L = length of the reservoir (meters), D = mean reservoir foresight (meters) (for which dam height can be a proxy), Q = mean water influx (cubic meters per second), and V = eservoir tidy sum (cubic meters). If F is less than 1, some stratification is evaluate, the severity of which increases with a smaller F. When F is greater than 1, stratification is not likely. H. utilizable beginning aliveness 18. reclaimable reservoir life is the expected number of age forrader a reservoirs inanimate fund is all in all fill, so that further alluviationation reduces the live entrepot and curtails power generation. numb(p) depot comprises all reservoir water beneath the level of the breathing ins for the dams turbines all of the water at or in a higher place this intake level is part of the live retentiveness. effective reservoir life is a function of utter repositing and river-borne depositary slews. Useful reservoir life is a good indicator of the relative sustainability of electric power generation it varies from less than ten years before dead storage is filled (such as the Paute Dam in Ecuador) to potentially thousands of years. In general, reservoirs with the bimestrial efficacious life are relatively deep and set on rivers with low sediment loads. Maintaining low sediment loads over time typically requires good drainage basin management. Good Dams and dreary Dams 11 I. glide slope Roads thro ugh Forests 19.Where the risks of induced deforestation are high, project siting should minimize the kilometers of required new or upgraded access roads passing through or near lifelike forests. J. Persons Requiring resettlement 20. The number of pot physically displaced by hydroelectric projects ranges from energy (e. g. Pehuenche, Chile) to over 50,000 in Latin America (e. g. Yacyreta, Argentina-Paraguay) and well over 1 million in Asia ( troika Gorges, China). Dam siting should in the main seek to minimize the number of individuals or households requiring resettlement from lands alter by the reservoir and complementary genteel works.A utile measure for relating resettlement costs to hydropower benefits is the ratio of people displaced per megawatt (Table 2). Because of their usually greater exposure to social disruption, it is especially in-chief(postnominal) to minimize the number of indigenousal people with traditional land-based models of production who would require resettlement. K. captious native Habitats unnatural 21. It is important to know the number of sites and hectares of vital natural habitats that would be alienated to inundation, suck in pits, or other project components.Critical natural habitats include animated and formally proposed protected areas, as well as unprotected areas of know high splendour for biodiversity conservation. To combine with the World Banks graphic Habitats Policy, hydroelectric projects should not cause any significant loss or debasement of exact natural habitats. On the other hand, some hydroelectric projects imply very important conservation opportunities by providing a robust excuse (sediment reduction) and financial resources needed for defend natural habitats in amphetamine catchment areas.L. fish Species renewal and indigenousness 22. search species diversity is the number of species cognise from the project area, including the dam and reservoir site, as well as the downstream zone of project influence. Fish species autochthony is the number of native species known only from the project area, or the river system where the project is located, and nowhere else on Earth. Dams are environmentally less objectionable if they affect rivers with a course low diversity and endemism of native fish species.In general, large, lowland rivers in straightaway (tropical or subtropical) climates project a high diversity of native fish and other aquatic organisms, piece small rivers in insentient (tropical alpine or temperate) climates deport relatively low diversity. Large, lowland rivers are likewise more likely to amaze significant seasonal worker fish migrations, which are in effect close up by most dams. However, subalpine rivers and streams often shoot relatively high endemism in their fish fauna, especially if they are degage from other rivers by waterfalls or other natural barriers.River segments with threaten fish species found nowhere else should be cat egorize as critical natural habitats and, ideally, would receive permanent protection from dams or other potentially damaging polished works. However, dams and reservoirs in amphetamine tributary rivers and streams need not threaten the survival of any endemic fish (or mollusks, or other aquatic life) if they affect only an insignificant portion of the river area used by these species (see Indicators D and E) they should also be sited so as not to block important fish migrations. M. ethnical billet affect 23.An reference of the ethnical substance of the area to be inundated (or otherwise moved(p) by the project) is the number (by type) of ethnical (archaeological, historical, paleontological, or religious) objects or sites. It is important to look whether each type of cultural property at the project site is saved (totally, partially, or not at all). 12 LCR sustainable Development working stem No. 16 Table 2. stain empyrean inundate and battalion Displaced in Large H ydropower Projects Project (country) Arun II (Nepal) Pehuenche (Chile) Pangue (Chile) Guavio (Colombia) Tehri (India) Ghazi Barotha (Pakistan)Nam Theun-Hinboun (Laos) Ertan (China) Fortuna (Panama) Chixoy (Guatemala) talkative Coulee (United States) Three Gorges (China) Tarbela (Pakistan) Salvajina (Colombia) Zimapan (Mexico) Itaipu (Brazil/Paraguay) capital of Seychelles (Sri Lanka) Kararao/Belo three-card monte (Brazil) Aguamilpa (Mexico) Betania (Colombia) Urra I (Colombia) Mangla (Pakistan) Bakun (Malaysia) Ataturk (Turkey) El Cajon (Honduras) Ilha Solteira (Brazil) Guri difficult (Venezuela) Salto Grande (Argentina/Uruguay) Nam Theun II (Laos) Arenal (Costa Rica) Yacyreta (Argentina/Paraguay) Tucurui (Brazil) Narmada Sagar (India) Porto Primavera (Brazil)Churchill travel (Canada) Khao Laem (Thailand) Kedung Ombo (Indonesia) Kainji (Nigeria) Pak Mun (Thailand) Cabora Bassa (Mozambique) Aswan gamy (Egypt) Nam Ngum (Laos) Sobradinho (Brazil) Kariba (Zambia/Zimbabwe) Balbina ( Brazil) Akosombo (Ghana) Bayano (Panama) Kompienga (Burkina Faso) Brokopondo (Suriname) Installed capacity (MW) 402 calciferol 450 1,000 2, cd 1,450 210 3,ccc three hundred ccc 6,494 18,200 3,478 270 280 12,600 210 8,381 960 510 340 1,000 2,400 2,400 three hundred 3,200 10,300 1,890 1,086 157 3,100 3,980 1,000 1,815 5,225 300 29 760 34 2,075 2,100 one hundred fifty 1,050 1,260 250 833 30 14 30 Reservoir rea (hectares) 43 400 ergocalciferol 1,530 4,200 2,640 630 10,100 1,050 1,400 33,306 110,000 24,280 2,030 2,300 135,000 2,270 116,000 13,000 7,370 7,400 25,300 70,000 81,700 11,200 125,700 426,000 78,300 45,000 7,000 165,000 243,000 90,820 225,000 665,000 38,800 4,600 126,000 6,000 380,000 400,000 37,000 415,000 510,000 236,000 848,200 35,000 20,000 160,000 People displaced 775 0 50 4,959 100,000 899 0 30,000 446 3,445 10,000 1,300,000 96,000 3,272 2,800 59,000 45,000 n. a. 1,000 544 6,200 90,000 9,000 55,000 4,000 6,150 1,500 n. a. 5,700 2,500 50,000 30,000 80,500 15,000 0 10,80 0 29,000 50,000 4,945