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In 1936, the first mega-dam, the HooverDam, was built on the Colorado River inBlack Canyon, near what was then the littletown of Las Vegas, Nevada. Standing 221 mhigh, three times the size of the Statue ofLiberty, it was the largest dam in the world.Its massive concrete walls held back thewaters of Lake Mead, a 160-km-long bodyof water heavy enough to bend the earth'scrust. Nine more large dams diverted theColorado River's water into Arizona,Nevada, and southern California, fuelingthe growth of major citiesand helping to turn thearid West into a lush andlucrative garden.

The Colorado damswere part of a dam-build-ing fever that encom-passed the globe. Damsharnessed the world'smajor rivers, includingthe Danube, the Nile, theZambezi, the Yangtze,and the Ganges. LikeIndian Prime MinisterJawaharlal Nehru, post-colonial leaders saw themas the new "temples ofdevelopment," monu-ments to a nationalisticvision of modernizationand unlimited growth,and vigorously promoted Shifting points oftheir construction. By now appears unre

1989, the Hoover Dam was only 15th inthe list of the world's largest dams.

According to Patrick McCully, cam-paigns director of the Berkeley, California-based International Rivers Network, over800,000 dams have been constructedworldwide for drinking water, flood con-trol, hydropower, irrigation, navigation,and water storage. But since the 1950s, thepeak of the big dam era, perceptions ofdams and dam building have changed.Once symbols of development, dams today

symbolize, for some critics, not progressbut environmental and social devastation.The benefits and detriments of dams havelocked opponents and proponents in hotdebate.

Decisions on dam building, once theprovince of governments and bureaucra-cies, are becoming a public processinvolving many stakeholders with differ-ent priorities. All stakeholders need aclear understanding of the possible ben-efits and potential consequences of

dams, as well as alterna-_E tives to dams, if they are-' to achieve a rational,

- m P sustainable solution.

reference. Once the biggest dam on earth, the Hoover Dam, built in 1936,markable compared to some of the world's more recently built mega-dams.

Dams andCivilizationFarmers and rulers havebeen impounding water formillennia. Eight thousandyears ago, the Sumeriansbuilt an irrigation-basedcivilization between theTigris and Euphratesrivers, then lost it to thesalinization that nowplagues some 20% ofIraq's arable territory. Bythe first century BC, lowdams had been built inthe Mediterranean, theMiddle East, CentralAmerica, and China.

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Focus * Is It Worth a Dam?

Limited technology kept their heightdown: a fifth-century Sri Lankan dam, 34m high, was the world's highest for a mil-lennium.

The age of hydropower and large damsemerged following the development of theturbine in 1832. By the turn of the centu-ry, hydro plants were operating in theUnited States, Italy, and Norway.Improvements in turbine design ushered inthe mega-dam boom in the 1930s. Asdam-building technology spread, fairlyautonomous government agencies like theBureau of Reclamation and the U.S. ArmyCorps of Engineers, and river managementagencies like the Tennessee ValleyAuthority (TVA), became the model forwater management authorities worldwide.

Today, most of the world's large riversare dammed. Of large rivers in the UnitedStates, only one-the Yellowstone-flowsfreely along its 1,000-km length.Worldwide, some 40,000 "large" dams(over 15 m high, according to theInternational Commission on LargeDams) and about 800,000 smaller oneshave been constructed. According toMcCully, the dams impound a total ofover 400,000 km2 of reservoirs-the areaof California-with an estimated capacityof as much as 10,000 km3, five times thevolume of all river water.

The Dam-busters' DebateThe original purposes of dams were toimprove human quality of life by provid-ing drinking water and to support eco-nomic growth by diverting water forpower, navigation, flood control, and irri-gation. In many ways, dams have succeed-ed. For example, the fields of Westernfarmers feed the United States and manyother parts of the world, and India's irriga-tion systems have enabled that country tobe self-sufficient in food production since1974. In addition, in many parts of theworld dams have helped to remedy life-threatening problems such as poverty from

lack of economicdevelopment, famineas a result of drought,devastation fromfloods, and continueddisease from lack ofpotable water sup-plies.

But the adverseeffects of river impound-ments-disruption ofecosystems, decline offish stocks, forced reset-dements, and disease-have of late made damssymbols of corporateand governmentalhubris. In his 1993book Desert Cadillac In the interest of fish.(the basis for a 1997 fish hatcheries (abovepublic televisionseries of the same name), author MarcReisner charges that dam-building agen-cies like the Bureau of Reclamation andthe U.S. Army Corps of Engineers"greened" the U.S. West, with often dis-astrous ecological and social results. "Wecan't imagine how dependent we'vebecome on the liberties we've taken withthe natural order," Reisner states in theTV series.

Opponents of dams, so-called "dam-busters," charge that government agencies,utilities, and international loan agenciessuch as the World Bank have created a net-work that fosters irresponsible and self-serving decisions when it comes to dambuilding. "When I studied engineering,dam building was presented as a rationalprocess, but most dam building is drivenby greed, or a dictator who wants a pro-ject," says Bill Jobin, an engineering con-sultant with Blue Nile, an environmentaland engineering consulting company inDolores, Colorado. Jobin criticizes govern-ments and lending agencies for "compart-mentalization," or failing to consider thefull range of consequences, including

Many dams, such as the Bonneville Dam, incorporate,lower right) into their design.

human health and environmental costs, indeciding whether to build a particulardam. He says this leads to "bad" dams-dams that ignore high environmental orhuman costs-being built despite theirpredicted consequences. Referring to thefact that the World Bank recently pulledout of a number of dam-building agree-ments because of environmental and socialcosts, he says, "With the World Bank'sstance, you'd think they'd know the score.But when it gets down to the loan officer,he just says, 'let's go."'

Some critics charge that many of thepromised benefits of dams built during thefirst part of the century have not material-ized, often because the engineering andplanning studies supporting such dam pro-jects were seriously flawed, if not con-trived, according to Sam Flaim, an econo-mist and engineering consultant based inGolden, Colorado. "The benefits of damsfor flood control and navigation were exag-gerated by bureaucracies who were in thebusiness of getting dams built," Flaim says."[Dams] were widely perceived as benefi-cial, and those benefits are now being

] S; ; i ffi;^5"~~~~~~~SS 3. ^Order Name River Country Type Height (m) Year Completed1 Kogun Vakhah Russia E-R 335 UC2 Nurek Vakhah Tajikistan E 300 19803 Grand Dixence Dixence Switzerland G 285 19614 Inguri Inguri Georgia A 272 19805 Chicoasen Grijalva Mexico R 261 19806 Tehri Bhagirathi India E-R 261 UC7 Kishau Toas India E-R 253 UC8 Ertan Yalong Jiang China A 245 UC9 Sayano-Shushensk Yenisei Russia A 245 UC10 Guavio Guavio Colombia R 243 UC

Type: E = Earthfill, R = Rockfill, E-R = Earth and Rockfill, G = Gravity, A = ArchUC, under constructionSource: National Performance of Dams Program/Stanford University at http//npdp.stanford.edu/ and the U.S. Committee on Large Dams Register of Dams

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Focus - Is It Worth a Dam?

questioned. Also, what was once perceivedas a benefit-interruption of naturalstream flows-is now perceived as a cost."Flaim adds, "Dams achieved exactly whatthe planners and engineers intended-interrupting large annual changes in streamflows so water would be available all year.Now we look at those realized intentions asnegative consequences. But there havebeen unforeseen benefits in the environ-ment, too: an increase in food and habitatfor raptors, trout fisheries. Dams are herenow; the issue is how to use them."

Dam-busters, proponents say, mustremember that, without the economic andsocial benefits that dams provide, muchdevelopment would be impossible. "Youhave to think of the benefits of dams inmonetary terms," says Earl Eiker, chief ofhydraulics at the U.S. Army Corps ofEngineers. "If you're going to have sustain-able development, you can't leave the envi-ronment totally pristine. This is a trade-offthat we must accept, though impacts onthe environment can and should be mini-mized. But without water resources devel-opment, this country wouldn't be what itis today. We all like to know that we willhave water when we turn on the taps, orlights when we flip the switch."

It is impractical and poor strategy tooppose all dams on principal. "Dam oppo-nents make a serious mistake when theydon't raise the right issues, and distinguishbetween different types of dams," saysRobert Tillman, senior environmental spe-cialist for Africa at the World Bank."There are more good dams than bad ones.The bad dams are the shallow ones thatflood large areas of land, or that producerelatively little power. It's in the tropicsthat these dams are associated with diseaseslike schistosomiasis and malaria; these arenot a problem in temperate areas. We alsoneed to revisit the definition of large dams:you can't call a 10-meter dam large whenyou have 190-meter dams. And with prop-er mitigation, dam sites can be improved."

The Biology ofImpoundmentDams change the chemical, physical, andbiological processes of river ecosystems.They alter free-flowing systems by reduc-ing river levels, blocking the flow of nutri-ents, changing water temperature and oxy-gen levels, and impeding or preventing fishand wildlife migration. These changes canbe beneficial or tragic, depending on yourperspective.

In its wild days, the Colorado Riverwas a silty, warm flow of water that ran2,300 km, ending in a rich delta inMexico. Today, northern Mexico gets onlya meager allotment of water that has been

recycled for irrigation as many as 18 times,according to Reisner, and the delta is dryexcept in years of exceptional rain. The 10dams on the Colorado have turned itswater clear and cold, inimical to the fishthat evolved to live it, such as the bonytailchub and the Colorado squawfish.Nonnative vegetation, especiallytamarisk-small shrubs and trees native toEurasia-has invaded the banks.

Notoriously, large dams like those onthe Colorado have contributed to hugedeclines in anadromous fish (those that livein the sea but swim inland to historicspawning grounds) such as salmon, shad,steelhead, and sturgeon. Dams are not theonly culprit-pollution and overfishinghave also contributed-but the combina-tion has virtually eliminated shad and stur-geon from the U.S. Atlantic coast, andsalmon from many rivers in Europe andthe American West and Northeast. Insome areas, such as the Chesapeake Baywatershed, stocked fish are trucked to theirspawning grounds.

Things are improving in the UnitedStates, where environmental laws andpublic pressure have forced utilities andbureaucracies to restore some of the natur-al flow of riverine ecosystems. In devel-oped countries, technological fixes havealso yielded results. The TVA has becomea leader in various technologies to returndissolved oxygen to tailwaters (water flow-ing out of dams). And a simulated springflood released in March 1996 in theGrand Canyon increased the volume ofexisting sandbar habitats by over 50%,and created new backwaters for nativefish. According to the July-August 1997issue of the Bay Journal, utilities and thepublic spent $50 million over a period of20 years for fish elevators and passages onthe Susquehanna River. In 1997, 100,000shad swam up the Chesapeake Bay to theirSusquehanna spawning grounds, up froma total catch of 167 in 1984.

But developing countries-in Asia, forexample, where stocks of the migratory(and commonly eaten) hilsa shad havedeclined-cannot afford such expensiveretrofits. Also, restoration of river ecosys-tems in the United States has created con-flicts between environmentalists, who wantto restore the natural system, and recre-ational groups, who are accustomed toswimming, boating, trout fishing, diving,and water skiing in thousands of artificiallycreated lakes and rivers. Recreational waterusers favor the preservation of newresources like these for sport activities."Some priorities for management seemmutually exclusive," says Flaim. "[On theColorado], environmental assessments

always focus on native fish that like warm,turgid water. Sport fishermen prefer gamefish like trout, which thrive in cold water.They tried to restock native fish where sed-iment load and temperatures were higher.But the sport fish eat the [young] of thenative fish."

Conflict between environmentalistsand proponents of regional power andagricultural uses, Flaim says, is the result ofdevelopment and rising environmentalawareness. "Once, [dam building] was aquestion of survival. Now we're trying toget the maximum value from naturalresources. Values today reflect preferencefor environmental attributes as well as eco-nomic development."

Water QualityDiving and recreational fishing are scarcelyconcerns for the majority of people indeveloping countries, however. What theyneed is clean, potable water. By someaccounts, an estimated 1 billion people inthe world do not have access to potablewater. And that means that reservoirs areneeded, Eiker says. "You can obtain waterdirectly from a big river, like the Ohio orthe Mississippi, where there's enough con-tinuous flow. But most major cities gettheir water from reservoirs created bydams."

In drought-ridden countries, reservoirsare vital for community and urban waterstorage, and new ones will likely need to becreated to respond to population expan-sion and the push for agricultural develop-ment. But reservoirs can be difficult tomaintain-reservoirs from large dams indrought-ridden areas evaporate huge quan-tities of water-and often result inincreased environmental problems andhuman health risks. Worldwide, a com-mon problem with reservoirs is that theytrap nutrient-laden sediments behind thedam. This reduces reservoir volumes andaccelerates a cycle of eutrophication (oroxygen depletion) that results in increasedplant and algal growth, bacterial decompo-sition that consumes oxygen, and release ofphosphorus that nourishes further algalgrowth.

"There's a massive buildup of organicmatter in the sediment," says Clifford W.Randall, the C.P. Lunsford professor ofenvironmental engineering at VirginiaPolytechnic Institute in Blacksburg. "Thiscan happen in any impoundment. Youcan have high levels of dissolved oxygen atthe top from the algal growth, and tenfeet below that-zero. So the top ten feetare the only habitable area for fish.What's more, when they decay, algaerelease organic compounds that are pre-

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cursors for potentially carcinogenic tri-halomethanes when the water is chlorinat-ed for drinking."

Tropical reservoirs and the irrigationnetworks they feed are also ideal breedinggrounds for mosquitoes, snails, and flies,the vectors that carry malaria, schistosomi-asis, and river blindness. Incidence ofschistosomiasis, the long-term conse-quences of which can indude pulmonarylesions, liver failure, and bladder cancer,has nearly doubled since the 1940s. A totalof 200 million people in 75 countries areinfected today, and 500-600 million are atrisk, according to an artide by G. ThomasStrickland, director of the internationalhealth program at the University ofMaryland School of Medicine, that waspublished in the 7th edition (1991) ofHunter's TropicalMedicine.

In many instances, infection can bedirectly correlated to the slow-flowing,reed-filled waters of irrigation canals. Theabsence of adequate sanitation only com-pounds the problem. Randall cites studieshe conducted near a large drinking andirrigation water reservoir in Kenya. "Therewas no waste disposal, with . . . excretafrom humans and cattle in the water. Itwas found that 78% of school children hadone or more forms of schistosomiasis, andover 80% had one or more forms of malar-ia." Randall adds that behavioral solutionslike keeping cows away from reservoirs andusing sanitary latrines would prevent schis-tosomiasis, but people often don't haveaccess to or use such technology. LoriPottinger, editor of the magazine WorldRivers Review, published by theInternational Rivers Network, says, "Toooften, governments in-developing countriesinvest huge amounts of money in costlylarge-scale river development projects likedams and irrigation schemes, rather thaninvesting in low-tech programs like watersupply and sanitation for communities."

Governments in developing countries,which are generally weak in health careinfrastructure, cannot respond effectivelyto reservoir-related epidemics. Nor arereservoir-related illnesses confined todeveloping countries. Outbreaks of cryp-tosporidiosis, a parasitic disease associatedwith fecal-oral contamination, have beenlinked to drinking water in the UnitedStates, most recendy in Las Vegas in 1995.These emerging hazards are related tourban growth and changing water uses."What's happening in the watershed ishappening in the reservoir," says James F.LaBounty, manager of the Bureau ofReclamation's research and investigationgroup. "As Las Vegas has grown, it'sdumped [domestic and industrial] treated

effluent into Las Vegas Wash, and pesti-cides, endocrine-disrupting chemicals, androcket fuel go into the groundwater. Thiswater flows into Boulder Basin [a portionof Lake Mead], and it may be contaminat-ing Las Vegas drinking water. We're get-ting into new uses for water that used tobe used for irrigation and power, and weneed a better understanding of reservoirbiology."

Hydropower: Clean Energy orDestroyer?In addition to the water they provide,dams also provide energy in the form ofelectrical hydropower. According to theWorld Bank, hydropower constitutes 13%of electrical power in the United States,99% in Norway, 75% in New Zealand,and 70% overall in Latin America. TheU.S. hydropower industry promoteshydropower as a clean, renewable, reliableenergy source that produces 19 gigawattsof electric power annually worldwide.Industry figures say that the U.S. annualcapacity of about 92,000 megawatts pro-duces as much electricity as 500 barrels ofoil or 150 coal power plants, and preventsthe emission of over 200 million tons ofcarbon dioxide annually.

Hydropower has been shown to be efficient. World Bank figures show that itconverts mechanical energy into electrical

By the old millstream. Hydropower has come along way in the last century, but is it far enough?

energy at 85% efficiency (TVA figures are90-92%), compared to 50% efficiency forgas turbines. Once constructed, hydroplants are inexpensive to run. Thehydropower of Western rivers helped theUnited States win World War II: theBonneville and Grand Coulee dams fueledenough aluminum processing to build60,000 planes, and at the power plant onthe Hanford Reservation near Richland,Washington, energy from the ColumbiaRiver produced the plutonium that endedthe war.

But increased understanding of theeffects of large-scale inundations of damwaters has qualified daims about the relia-bility and cleanliness of hydropower.According to Pottinger, hydropower plantsare often unsustainable in countries wherefrequent droughts cripple power produc-tion. A notable example, she cites, is theAkasombo Dam in Ghana, whose powerplant has suffered severe drought-causedpower outages for years, resulting in black-outs and interruptions in power to busi-nesses and homes.

Then there are health issues. In general,hydropower produces little carbon dioxide,except for the cement and steel used inconstruction, according to RobertGoodland, environmental advisor to theWorld Bank, in the spring/summer 1997issue of Civil Engineering Practice.However, large, shallow reservoirs, espe-cially in the tropics, can generate largeamounts of greenhouse gases from thedecay of biomass. A 1996 study at theUniversity of Manitoba, described in theMay 1997 issue of Environmental Science,provides evidence that, even in temperatezones, inundating wetlands changes themfrom net sinks to major emitters of carbondioxide and methane gases, and increasesthe catalysis of methylmercury, a nervetoxin, from inorganic mercury in sedi-ments. "The worst hydropower projectsmay produce more [greenhouse gases] thana coal-fired equivalent," Goodland writes.

Critics also take issue with the claimthat hydropower comes cheaply.Historically, planners for large dams haveignored numerous additional cost factors,including potential structural difficulties,human resettlement costs, and environ-mental consequences. By all accounts, dambuilding in developing countries is fraughtwith corruption. Dam construction alsofrequently costs more and takes longerthan anticipated, sometimes to a grotesquedegree. For example, the cost of buildingBrazil's Itaipu Dam, estimated at $3.4 bil-lion over 15 years, expanded to $20 billionover 18 years. Since capital' costs representabout 80% of expenditures over the life-

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time of a hydrodam project, such costoverruns are a serious issue. Dam oppo-nents add that the cost-effectiveness ofhydropower is further eroded by subsidiesfor industrial users and, sometimes, byconsiderable siltation, which can reducedam capacity, thereby diminishing generat-ing power, or deplete downstream farm-lands, which are dependent upon silt fornutrients.

Technological solutions such as dredg-ing and mixing, though expensive, canalleviate these problems in existing dams.But more importantly, says Jobin, newdams should incorporate understandinggained from past mistakes. "When youbuild a dam to fit the season of the river-a low dam or a gated one-it can pass thesediment," he says. "But many dams arebuilt without bottom outlets, just a spill-way at the top."

One of the most serious charges againsthydropower, though it applies to all dams,is its high social cost in terms of involun-tary resettlement. McCully estimates that30 million people have been ousted bydams. Most often, "oustees" are poor orindigenous people who often leave behindproductive farms and ancestral homes.Opponents claim that, though thesegroups pay the social and environmentalcosts of dam construction, they don'treceive the benefits-instead, those go tourban areas and industries. The AswanHigh Dam ousted 100,000 people, accord-ing to the World Bank, and the plannedThree Gorges Dam in China, a 600-foot-thick, mile-wide project so large it will bevisible from outer space, will expel 1.3 mil-lion people from the area.

Opponents claim that relocation can bea death sentence to a community. SaysJobin, "The dislocation itself causes mentaland spiritual problems. Twenty years after[about 90,000 people were] relocated forhydroelectric power projects in Ghana,none of them could be found. They'dmigrated to cities, or died. You'd think this

The great dam of China. The Three Gorges Dam,planned for China, will be large enough to be seenfrom outer space.

only happens overseas, but it's happened[in the United States] with Indian tribes."

The World Energy Commission pre-dicts that global energy consumption willlikely double between 1990 and 2020,with demand growing fastest in less devel-oped countries. With international consen-sus developing over the potential for globalwarming, well-designed hydropower plantscan still provide cleaner power than otherfuels, except possibly natural gas.

Development organizations and thedam industry agree on the need to identifyand internalize the environmental andsocial costs of dams, even if that means notbuilding some dams. "There needs to be anhonest assessment of costs," says Tillman."With oil prices low, you can figure that ifyour construction involves more than$1,500-2,000 per kilowatt hour, it'sunlikely to be economically feasible."

Order Name River Country Capacity (MW) Year Completed1 ltaipu Parana Brazil/Paraguay 12,600 19832 Guri Caroni Venezuela 10,300 19863 Sayano-Shushensk Yenisei Russia 6,400 19894 Grand Coulee Columbia USA 6,180 19425 Krasnoyacsk Yenisei Russia 6,000 19686 Church Falls Churchill Canada 5,428 19717 La Grande 2 La Grande Canada 5,328 19798 Bratsk Angara Russia 4,500 19619 Ust-Ilim Angara Russia 4,320 197710 Tucurui Tocantins Brazil 3,960 1984

Source: National Performance of Dams Program/Stanford University at httpl/npdp.stanford.edu/ andthe U.S. Committee on Large Dams Register of Dams

Tillman adds that when countries canagree, cross-boundary water sales or watersharing could furnish an incentive to find"good" dam sites that provide power with-out demanding resettlement. Numerousarrangements for interstate water exchangeexist in the United States, and a number ofdeveloping countries, including SouthAfrica, Uganda, and Paraguay, sell or resellexcess hydropower.

Flood Control, Irrigation, andEconomic GrowthHistorically, dams and the lakes they createhave protected growing populations fromthe unpredictability and violence of rivers'seasons. In warm regions, stored floodwa-ters can supply enough irrigation for ayear-round growing season. Reisner reportsthat California's San Joaquin Valley, oncea swampland with seasonal flooding, nowprovides a quarter of America's foodthrough intensive ground- and surface-water irrigation. Egypt's Aswan High Damhas provided power, irrigation, and thewater supply for a growing population foralmost 30 years, with three yearly cropsincluding high-yield grains or water-inten-sive cash crops like sugar cane and rice.

However, though irrigation is appro-priate in rain-rich lands, in arid climates itcan result in salinization of soil and water,stunting or killing crops unless even morewater is used to flush the salt out. Andover-irrigation, combined with the loss ofnutrient-rich sediments through naturalflooding, can also cause numerous down-stream changes. According to journalistFred Pearce's 1992 book The Dammed, theAswan High Dam's impoundment of 120million tons of silt has vastly depleted theEgyptian sardine industry's fish stocks,which once fed on organisms that werenourished by the 30,000 tons of siltdeposited each year in the Nile delta.Pearce adds that the absence of silt has alsomade Egypt dependent on chemical fertil-izers, at the rate of 175 kg per hectare onsome 25,000 km2 of farmland. Over-watering deposits 1 ton of salt per hectareper year on some lands, while the growthof Cairo, fueled by Aswan's water andpower, buries fertile land that could befarmed. Pearce reports that Egypt hasbecome a net importer of food.

According to the United Nations' Foodand Agriculture Organization, 10% of the270 million hectares of lands irrigatedglobally are damaged by salinization, andanother 20% are showing symptoms ofdamage. Though gene modification anddevelopment and cultivation of salt-resis-tant plants can address some of these prob-lems, they do not yet promise a sustainable

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solution. Experts say that water conserva-tion techniques such as recycling and dripirrigation can maintain productivity using30-50% less water. But critics question avision of development that demands largeallocations of water to ecosystems that arehostile to cultivation.

Nor does irrigation address the issue ofover-allocation of water. When countriesshare water, over-allocation combined withnew upstream uses can threaten not justhuman health, but political stability.Egypt, for example, is the last of ninecountries through which the Nile flows. IfEthiopia makes good on its intention todam the Blue Nile, Egypt could lose wateron which it depends. Sandra Postel is asenior fellow at the Washington, DC-based Worldwatch Institute, which pub-lishes the journal World Watch. In an arti-cle in the July 1993 issue of World Watch,Postel writes, "As Egypt's water securitybecomes increasingly jeopardized by newprojects in Ethiopia, tensions between thecountries are sure to build."

Government and water-managementplanners have yet to address the full spec-trum of how to sustainably manageincreasing demand. "If water is over-appropriated, why do we continue to buildwithout restriction?" says LaBounty, refer-ring to projects in the western UnitedStates. "There's no really good answer.What we need to do is to manage waterproperly from the inside, starting at thesanitation districts and water boards, andworking up through the state legislation."

Ultimately, the vision of ever-expand-ing agricultural growth will need revision."Large irrigation schemes have proven notto be cost-effective compared to smaller,locally controlled operations," saysTillman. "The ideas in [E.F.] Schumacher'sSmall is Beautiful [a 1973 book that pro-motes smaller, locally controlled produc-tion schemes as working more effectively]are coming back in."

Water and the Future ofDevelopmentDam opponents have seen many victoriesrecently. In the United States, dam-build-ing decisions are becoming increasinglypublic. Representatives of environmentaland recreation organizations, utilities,engineers, and the dam industry negotiatedecisions on the construction and relicens-ing of dams. In June 1997, public inputresulted in a federal decision to remove the3.5 megawatt Edwards Dam in Augusta,Maine, a change that is expected to benefitnine species of migratory fish. Worldwide,protests against the social, environmental,and economic costs of dam building and

refurbishing have led to the removal ofdams or cancellation of dam-building pro-jects. In April 1997, in a move applaudedby the environmentalist community, theWorld Bank agreed to the creation of anindependent commission to review thesoundness of dams and dam projects. Thecommission will reviewexisting, ongoing, and pro-posed projects (not just theWorld Bank's), and recom-mend ways of redressingdamage to populations andnatural systems that havebeen adversely affected bydams. The commission isto be launched inNovember 1997. Its mem-bers, who will be selected

for water and power. And they can dothem well or miserably. We need to buildup the institutions overseas to improveconstruction and deal with health andsocial problems that come up once they'reconstructed. That's a long-term project-10 or 15 years."

Stairway to heaven. Fish elevators, such as thisone at the John Day Dam, allow migratoryspecies to continue to visit traditional spawninggrounds.

by an interim joint World Bank andWorld Conservation Union staff, willinclude World Bank officials, critics oflarge dams, and representatives from bothdam-building agencies and populationsaffected by dams.

Deregulation of energy prices, theabsence of good sites, and requirementsthat utilities pay for nonpower benefitsresulting from harnessing a river'sstrength-which includes benefits that arelargely recreational, such as sport fishing,rafting, boating, and wildlife programs-will likely diminish the attractiveness ofdams, especially hydropower dams, indeveloped countries. Hydropower develop-ment in the United States is now stagnant,although the Department of Energy esti-mates that many thousands of powerplants could be added to existing dams.Overseas, however, the demand for dams isstill strong, particularly in Asia. Given theweak infrastructures and lax environmentallaws there, the potential for continuedunderestimation of environmental andsocial costs concerns many dam critics."Compliance [with international stan-dards] is the biggest issue," says TomRusso, special assistant to the director atthe Office of Hydropower Licensing at theU.S. Federal Energy Regulatory Com-mission, which regulates privately ownedhydropower dams. "Countries need dams

Rational decisions about dam buildingwill require a review of the attitudes thatled to their construction-attitudes on thesustainability and feasibility of large-scaledevelopment. Though developing coun-tries need energy and water, their long-term sustainability also depends on otherfactors. "I go into energy projects thinkingthere must be a better way [than building anew dam]," says Tillman. "You ought tobe able to take a country and say, 'Usemore efficient technology. Stabilize yourpopulation. And make sure that your billsare going to be paid."'

Proponents and opponents generallyagree that the large dam era is probablyover. But dams are not likely to go awayfor a while. "Like it or not, we'll have tobuild more. And developing countries willprobably need big ones," says Jobin. "Butin the U.S., we have a good record of whathappens when you build with short-terminterests, and we can see the mistakes wemade. We ought to learn from them."

Stephanie Joyce

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